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Sample records for aircraft particle emissions

  1. Aircraft Particle Emissions eXperiment (APEX)

    NASA Technical Reports Server (NTRS)

    Wey, C. C.; Anderson, B. E.; Hudgins, C.; Wey, C.; Li-Jones, X.; Winstead, E.; Thornhill, L. K.; Lobo, P.; Hagen, D.; Whitefield, P.

    2006-01-01

    APEX systematically investigated the gas-phase and particle emissions from a CFM56-2C1 engine on NASA's DC-8 aircraft as functions of engine power, fuel composition, and exhaust plumage. Emissions parameters were measured at 11 engine power, settings, ranging from idle to maximum thrust, in samples collected at 1, 10, and 30 m downstream of the exhaust plane as the aircraft burned three fuels to stress relevant chemistry. Gas-phase emission indices measured at 1 m were in good agreement with the ICAO data and predictions provided by GEAE empirical modeling tools. Soot particles emitted by the engine exhibited a log-normal size distribution peaked between 15 and 40 nm, depending on engine power. Samples collected 30 m downstream of the engine exhaust plane exhibited a prominent nucleation mode.

  2. Physical characterization of the fine particle emissions from commercial aircraft engines during the Aircraft Particle Emissions Experiment (APEX) 1 to 3

    EPA Science Inventory

    The f1me particulate matter (PM) emissions from nine commercial aircraft engine models were determined by plume sampling during the three field campaigns of the Aircraft Particle Emissions Experiment (APEX). Ground-based measurements were made primarily at 30 m behind the engine ...

  3. An inventory of particle and gaseous emissions from large aircraft thrust engine operations at an airport

    NASA Astrophysics Data System (ADS)

    Mazaheri, M.; Johnson, G. R.; Morawska, L.

    2011-07-01

    Published particle number emission factors for aircraft operations remain very sparse and so far such emissions have not been included in the International Civil Aviation Organization (ICAO) databases. This work addresses this gap in knowledge by utilizing recent progress in the quantification of aircraft particle emissions. Annual emissions of particle number (PN), particle mass (PM 2.5) and NO x throughout the aircraft landing and takeoff (LTO) cycles and ground running procedures (GRP) are presented for aircraft using Brisbane Airport BNE (domestic and international). The aircraft are grouped according to an airframe based classification system. The resulting data are then used to develop an emissions inventory for large aircraft thrust engine operations on the ground, during LTO cycles and GRP, at the Airport. Annual PN, PM 2.5 and NO x emissions from large aircraft operations during LTO cycles and GRP at BNE were 1.98 × 10 24 yr -1, 1.35 × 10 4 kg yr -1 and 8.13 × 10 5 kg yr -1, respectively. Results showed that LTO cycles contribute more than 97% of these annual emissions at BNE in comparison to GRP related emissions. Analysis of the LTO cycle contribution to the daily emissions showed that the contribution of the climbout mode is considerably higher than for other individual LTO operational modes. Emissions during aircraft departures were significantly higher than those during arrival operations, due to the higher aircraft engine emission rates during takeoff and climbout.

  4. Gas Emissions Acquired during the Aircraft Particle Emission Experiment (APEX) Series

    NASA Technical Reports Server (NTRS)

    Changlie, Wey; Chowen, Chou Wey

    2007-01-01

    NASA, in collaboration with other US federal agencies, engine/airframe manufacturers, airlines, and airport authorities, recently sponsored a series of 3 ground-based field investigations to examine the particle and gas emissions from a variety of in-use commercial aircraft. Emissions parameters were measured at multiple engine power settings, ranging from idle to maximum thrust, in samples collected at 3 different down stream locations of the exhaust. Sampling rakes at nominally 1 meter down stream contained multiple probes to facilitate a study of the spatial variation of emissions across the engine exhaust plane. Emission indices measured at 1 m were in good agreement with the engine certification data as well as predictions provided by the engine company. However at low power settings, trace species emissions were observed to be highly dependent on ambient conditions and engine temperature.

  5. Particle and gaseous emissions from commercial aircraft at each stage of the landing and takeoff cycle.

    PubMed

    Mazaheri, M; Johnson, G R; Morawska, L

    2009-01-15

    A novel technique was used to measure emission factors for commonly used commercial aircraft including a range of Boeing and Airbus airframes under real world conditions. Engine exhaust emission factors for particles in terms of particle number and mass (PM2.5), along with those for CO2 and NOx, were measured for over 280 individual aircraft during the various modes of landing/takeoff (LTO) cycle. Results from this study show that particle number, and NOx emission factors are dependent on aircraft engine thrust level. Minimum and maximum emissions factors for particle number, PM2.5, and NOx emissions were found to be in the range of 4.16 x 10(15)-5.42 x 10(16) kg(-1), 0.03-0.72 g.kg(-1), and 3.25-37.94 g.kg(-1), respectively, for all measured airframes and LTO cycle modes. Number size distributions of emitted particles for the naturally diluted aircraft plumes in each mode of LTO cycle showed that particles were predominantly in the range of 4-100 nm in diameter in all cases. In general, size distributions exhibit similar modality during all phases of the LTO cycle. A very distinct nucleation mode was observed in all particle size distributions, except for taxiing and landing of A320 aircraft. Accumulation modes were also observed in all particle size distributions. Analysis of aircraft engine emissions during LTO cycle showed that aircraft thrust level is considerably higher during taxiing than idling suggesting that International Civil Aviation Organization (ICAO) standards need to be modified as the thrust levels for taxi and idle are considered to be the same (7% of total thrust) (Environmental Protection, Annex 16, Vol. II, Aircraft Engine Emissions, 2nd ed.; ICAO--International Civil Aviation Organization: Montreal, 1993).

  6. Chemical characterization of the fine particle emissions from commercial aircraft engines during the Aircraft Particle Emissions eXperiment (APEX) 1 to 3

    EPA Science Inventory

    This paper addresses the need for detailed chemical information on the fine particulate matter (PM2.5) generated by commercial aviation engines. The exhaust plumes of nine engine models were sampled during the three test campaigns of the Aircraft Particle Emissions eXperiment (AP...

  7. Characterization of emissions from commercial aircraft engines during the Aircraft Particle Emissions eXperiment (APEX) 1 to 3

    EPA Science Inventory

    The fine particulate matter emissions from aircraft operations at large airports located in areas of the U. S. designated as non-attainment for the National Ambient Air Quality Standard for PM-2.5 are of major environmental concern. PM emissions data for commercial aircraft engin...

  8. Composition and morphology of particle emissions from in-use aircraft during takeoff and landing.

    PubMed

    Mazaheri, Mandana; Bostrom, Thor E; Johnson, Graham R; Morawska, Lidia

    2013-05-21

    In order to provide realistic data for air pollution inventories and source apportionment at airports, the morphology and composition of ultrafine particles (UFP) in aircraft engine exhaust were measured and characterized. For this purpose, two independent measurement techniques were employed to collect emissions during normal takeoff and landing operations at Brisbane Airport, Australia. PM1 emissions in the airfield were collected on filters and analyzed using the particle-induced X-ray emission (PIXE) technique. Morphological and compositional analyses of individual ultrafine particles in aircraft plumes were performed on silicon nitride membrane grids using transmission electron microscopy (TEM) combined with energy-dispersive X-ray microanalysis (EDX). TEM results showed that the deposited particles were in the range of 5-100 nm in diameter, had semisolid spherical shapes and were dominant in the nucleation mode (18-20 nm). The EDX analysis showed the main elements in the nucleation particles were C, O, S, and Cl. The PIXE analysis of the airfield samples was generally in agreement with the EDX in detecting S, Cl, K, Fe, and Si in the particles. The results of this study provide important scientific information on the toxicity of aircraft exhaust and their impact on local air quality.

  9. CO2, NOx, and particle emissions from aircraft and support activities at a regional airport.

    PubMed

    Klapmeyer, Michael E; Marr, Linsey C

    2012-10-16

    The goal of this research was to quantify emissions of carbon dioxide (CO(2)), nitrogen oxides (NO(x)), particle number, and black carbon (BC) from in-use aircraft and related activity at a regional airport. Pollutant concentrations were measured adjacent to the airfield and passenger terminal at the Roanoke Regional Airport in Virginia. Observed NO(x) emission indices (EIs) for jet-powered, commuter aircraft were generally lower than those contained in the International Civil Aviation Organization databank for both taxi (same as idle) and takeoff engine settings. NO(x) EIs ranged from 1.9 to 3.7 g (kg fuel)(-1) across five types of aircraft during taxiing, whereas EIs were consistently higher, 8.8-20.6 g (kg fuel)(-1), during takeoff. Particle number EIs ranged from 1.4 × 10(16) to 7.1 × 10(16) (kg fuel)(-1) and were slightly higher in taxi mode than in takeoff mode for four of the five types of aircraft. Diurnal patterns in CO(2) and NO(x) concentrations were influenced mainly by atmospheric conditions, while patterns in particle number concentrations were attributable mainly to patterns in aircraft activity. CO(2) and NO(x) fluxes measured by eddy covariance were higher at the terminal than at the airfield and were lower than found in urban areas.

  10. Chemical characterization of the fine particle emissions from commercial aircraft engines during the Aircraft Particle Emissions eXperiment (APEX) 1 to 3.

    PubMed

    Kinsey, J S; Hays, M D; Dong, Y; Williams, D C; Logan, R

    2011-04-15

    This paper addresses the need for detailed chemical information on the fine particulate matter (PM) generated by commercial aviation engines. The exhaust plumes of seven turbofan engine models were sampled as part of the three test campaigns of the Aircraft Particle Emissions eXperiment (APEX). In these experiments, continuous measurements of black carbon (BC) and particle surface-bound polycyclic aromatic compounds (PAHs) were conducted. In addition, time-integrated sampling was performed for bulk elemental composition, water-soluble ions, organic and elemental carbon (OC and EC), and trace semivolatile organic compounds (SVOCs). The continuous BC and PAH monitoring showed a characteristic U-shaped curve of the emission index (EI or mass of pollutant/mass of fuel burned) vs fuel flow for the turbofan engines tested. The time-integrated EIs for both elemental composition and water-soluble ions were heavily dominated by sulfur and SO(4)(2-), respectively, with a ∼2.4% median conversion of fuel S(IV) to particle S(VI). The corrected OC and EC emission indices obtained in this study ranged from 37 to 83 mg/kg and 21 to 275 mg/kg, respectively, with the EC/OC ratio ranging from ∼0.3 to 7 depending on engine type and test conditions. Finally, the particle SVOC EIs varied by as much as 2 orders of magnitude with distinct variations in chemical composition observed for different engine types and operating conditions.

  11. Emissions of NOx, particle mass and particle numbers from aircraft main engines, APU's and handling equipment at Copenhagen Airport

    NASA Astrophysics Data System (ADS)

    Winther, Morten; Kousgaard, Uffe; Ellermann, Thomas; Massling, Andreas; Nøjgaard, Jacob Klenø; Ketzel, Matthias

    2015-01-01

    This paper presents a detailed emission inventory for NOx, particle mass (PM) and particle numbers (PN) for aircraft main engines, APU's and handling equipment at Copenhagen Airport (CPH) based on time specific activity data and representative emission factors for the airport. The inventory has a high spatial resolution of 5 m × 5 m in order to be suited for further air quality dispersion calculations. Results are shown for the entire airport and for a section of the airport apron area ("inner apron") in focus. The methodology presented in this paper can be used to quantify the emissions from aircraft main engines, APU and handling equipment in other airports. For the entire airport, aircraft main engines is the largest source of fuel consumption (93%), NOx, (87%), PM (61%) and PN (95%). The calculated fuel consumption [NOx, PM, PN] shares for APU's and handling equipment are 5% [4%, 8%, 5%] and 2% [9%, 31%, 0%], respectively. At the inner apron area for handling equipment the share of fuel consumption [NOx, PM, PN] are 24% [63%, 75%, 2%], whereas APU and main engines shares are 43% [25%, 19%, 54%], and 33% [11%, 6%, 43%], respectively. The inner apron NOx and PM emission levels are high for handling equipment due to high emission factors for the diesel fuelled handling equipment and small for aircraft main engines due to small idle-power emission factors. Handling equipment is however a small PN source due to the low number based emission factors. Jet fuel sulphur-PM sensitivity calculations made in this study with the ICAO FOA3.0 method suggest that more than half of the PM emissions from aircraft main engines at CPH originate from the sulphur content of the fuel used at the airport. Aircraft main engine PN emissions are very sensitive to the underlying assumptions. Replacing this study's literature based average emission factors with "high" and "low" emission factors from the literature, the aircraft main engine PN emissions were estimated to change with a

  12. Measurement and Modeling of Volatile Particle Emissions from Military Aircraft

    DTIC Science & Technology

    2011-10-01

    distribution of the emissions. The smog chamber experiments demonstrated that photo-oxidation creates substantial secondary particulate matter, greatly...19 Dilution sampler.................................................................................................. 19 Smog chamber...The T63 engine test cell was located inside the building. The smog chamber and other sampling equipment were located outside

  13. From Contrails and Smoke Trails to Exhaust Particle Processes: A Brief History of Aircraft Particulate Emissions

    DTIC Science & Technology

    2011-12-01

    2,6- Dimethylnaphthalene Acenaphthylene Acenaphthene Phenanthrene Anthracene Fluoranthene Benz[ a ]anthracene Benzofluoranthenes Benzo [ a ] pyrene Indeno...1,2,3-c,d] pyrene Benzo [g,h,i]perylene Methane Ethane Propane Acetylene Propene n-Pentane n-Hexane Toluene n-Decane Dodecane Tridecane Formaldehyd e...Aerodyne Research, Inc. From Contrails and Smoke Trails to Exhaust Particle Processes: A brief history of aircraft particulate emissions Presented

  14. Ultrafine particle size as a tracer for aircraft turbine emissions.

    PubMed

    Riley, Erin A; Gould, Timothy; Hartin, Kris; Fruin, Scott A; Simpson, Christopher D; Yost, Michael G; Larson, Timothy

    2016-08-01

    Ultrafine particle number (UFPN) and size distributions, black carbon, and nitrogen dioxide concentrations were measured downwind of two of the busiest airports in the world, Los Angeles International Airport (LAX) and Hartsfield-Jackson International Airport (ATL - Atlanta, GA) using a mobile monitoring platform. Transects were located between 5 km and 10 km from the ATL and LAX airports. In addition, measurements were taken at 43 additional urban neighborhood locations in each city and on freeways. We found a 3-5 fold increase in UFPN concentrations in transects under the landing approach path to both airports relative to surrounding urban areas with similar ground traffic characteristics. The latter UFPN concentrations measured were distinct in size distributional properties from both freeways and across urban neighborhoods, clearly indicating different sources. Elevated concentrations of Black Carbon (BC) and NO2 were also observed on airport transects, and the corresponding pattern of elevated BC was consistent with the observed excess UFPN concentrations relative to other urban locations.

  15. Ultrafine particle size as a tracer for aircraft turbine emissions

    NASA Astrophysics Data System (ADS)

    Riley, Erin A.; Gould, Timothy; Hartin, Kris; Fruin, Scott A.; Simpson, Christopher D.; Yost, Michael G.; Larson, Timothy

    2016-08-01

    Ultrafine particle number (UFPN) and size distributions, black carbon, and nitrogen dioxide concentrations were measured downwind of two of the busiest airports in the world, Los Angeles International Airport (LAX) and Hartsfield-Jackson International Airport (ATL - Atlanta, GA) using a mobile monitoring platform. Transects were located between 5 km and 10 km from the ATL and LAX airports. In addition, measurements were taken at 43 additional urban neighborhood locations in each city and on freeways. We found a 3-5 fold increase in UFPN concentrations in transects under the landing approach path to both airports relative to surrounding urban areas with similar ground traffic characteristics. The latter UFPN concentrations measured were distinct in size distributional properties from both freeways and across urban neighborhoods, clearly indicating different sources. Elevated concentrations of Black Carbon (BC) and NO2 were also observed on airport transects, and the corresponding pattern of elevated BC was consistent with the observed excess UFPN concentrations relative to other urban locations.

  16. Biofuel blending reduces particle emissions from aircraft engines at cruise conditions

    NASA Astrophysics Data System (ADS)

    Moore, Richard H.; Thornhill, Kenneth L.; Weinzierl, Bernadett; Sauer, Daniel; D’Ascoli, Eugenio; Kim, Jin; Lichtenstern, Michael; Scheibe, Monika; Beaton, Brian; Beyersdorf, Andreas J.; Barrick, John; Bulzan, Dan; Corr, Chelsea A.; Crosbie, Ewan; Jurkat, Tina; Martin, Robert; Riddick, Dean; Shook, Michael; Slover, Gregory; Voigt, Christiane; White, Robert; Winstead, Edward; Yasky, Richard; Ziemba, Luke D.; Brown, Anthony; Schlager, Hans; Anderson, Bruce E.

    2017-03-01

    Aviation-related aerosol emissions contribute to the formation of contrail cirrus clouds that can alter upper tropospheric radiation and water budgets, and therefore climate. The magnitude of air-traffic-related aerosol–cloud interactions and the ways in which these interactions might change in the future remain uncertain. Modelling studies of the present and future effects of aviation on climate require detailed information about the number of aerosol particles emitted per kilogram of fuel burned and the microphysical properties of those aerosols that are relevant for cloud formation. However, previous observational data at cruise altitudes are sparse for engines burning conventional fuels, and no data have previously been reported for biofuel use in-flight. Here we report observations from research aircraft that sampled the exhaust of engines onboard a NASA DC-8 aircraft as they burned conventional Jet A fuel and a 50:50 (by volume) blend of Jet A fuel and a biofuel derived from Camelina oil. We show that, compared to using conventional fuels, biofuel blending reduces particle number and mass emissions immediately behind the aircraft by 50 to 70 per cent. Our observations quantify the impact of biofuel blending on aerosol emissions at cruise conditions and provide key microphysical parameters, which will be useful to assess the potential of biofuel use in aviation as a viable strategy to mitigate climate change.

  17. Biofuel blending reduces particle emissions from aircraft engines at cruise conditions.

    PubMed

    Moore, Richard H; Thornhill, Kenneth L; Weinzierl, Bernadett; Sauer, Daniel; D'Ascoli, Eugenio; Kim, Jin; Lichtenstern, Michael; Scheibe, Monika; Beaton, Brian; Beyersdorf, Andreas J; Barrick, John; Bulzan, Dan; Corr, Chelsea A; Crosbie, Ewan; Jurkat, Tina; Martin, Robert; Riddick, Dean; Shook, Michael; Slover, Gregory; Voigt, Christiane; White, Robert; Winstead, Edward; Yasky, Richard; Ziemba, Luke D; Brown, Anthony; Schlager, Hans; Anderson, Bruce E

    2017-03-15

    Aviation-related aerosol emissions contribute to the formation of contrail cirrus clouds that can alter upper tropospheric radiation and water budgets, and therefore climate. The magnitude of air-traffic-related aerosol-cloud interactions and the ways in which these interactions might change in the future remain uncertain. Modelling studies of the present and future effects of aviation on climate require detailed information about the number of aerosol particles emitted per kilogram of fuel burned and the microphysical properties of those aerosols that are relevant for cloud formation. However, previous observational data at cruise altitudes are sparse for engines burning conventional fuels, and no data have previously been reported for biofuel use in-flight. Here we report observations from research aircraft that sampled the exhaust of engines onboard a NASA DC-8 aircraft as they burned conventional Jet A fuel and a 50:50 (by volume) blend of Jet A fuel and a biofuel derived from Camelina oil. We show that, compared to using conventional fuels, biofuel blending reduces particle number and mass emissions immediately behind the aircraft by 50 to 70 per cent. Our observations quantify the impact of biofuel blending on aerosol emissions at cruise conditions and provide key microphysical parameters, which will be useful to assess the potential of biofuel use in aviation as a viable strategy to mitigate climate change.

  18. Performance Evaluation of Particle Sampling Probes for Emission Measurements of Aircraft Jet Engines

    NASA Technical Reports Server (NTRS)

    Lee, Poshin; Chen, Da-Ren; Sanders, Terry (Technical Monitor)

    2001-01-01

    Considerable attention has been recently received on the impact of aircraft-produced aerosols upon the global climate. Sampling particles directly from jet engines has been performed by different research groups in the U.S. and Europe. However, a large variation has been observed among published data on the conversion efficiency and emission indexes of jet engines. The variation results surely from the differences in test engine types, engine operation conditions, and environmental conditions. The other factor that could result in the observed variation is the performance of sampling probes used. Unfortunately, it is often neglected in the jet engine community. Particle losses during the sampling, transport, and dilution processes are often not discussed/considered in literatures. To address this issue, we evaluated the performance of one sampling probe by challenging it with monodisperse particles. A significant performance difference was observed on the sampling probe evaluated under different temperature conditions. Thermophoretic effect, nonisokinetic sampling and turbulence loss contribute to the loss of particles in sampling probes. The results of this study show that particle loss can be dramatic if the sampling probe is not well designed. Further, the result allows ones to recover the actual size distributions emitted from jet engines.

  19. Determination of PM mass emissions from an aircraft turbine engine using particle effective density

    NASA Astrophysics Data System (ADS)

    Durdina, L.; Brem, B. T.; Abegglen, M.; Lobo, P.; Rindlisbacher, T.; Thomson, K. A.; Smallwood, G. J.; Hagen, D. E.; Sierau, B.; Wang, J.

    2014-12-01

    Inventories of particulate matter (PM) emissions from civil aviation and air quality models need to be validated using up-to-date measurement data corrected for sampling artifacts. We compared the measured black carbon (BC) mass and the total PM mass determined from particle size distributions (PSD) and effective density for a commercial turbofan engine CFM56-7B26/3. The effective density was then used to calculate the PM mass losses in the sampling system. The effective density was determined using a differential mobility analyzer and a centrifugal particle mass analyzer, and increased from engine idle to take-off by up to 60%. The determined mass-mobility exponents ranged from 2.37 to 2.64. The mean effective density determined by weighting the effective density distributions by PM volume was within 10% of the unit density (1000 kg/m3) that is widely assumed in aircraft PM studies. We found ratios close to unity between the PM mass determined by the integrated PSD method and the real-time BC mass measurements. The integrated PSD method achieved higher precision at ultra-low PM concentrations at which current mass instruments reach their detection limit. The line loss model predicted ∼60% PM mass loss at engine idle, decreasing to ∼27% at high thrust. Replacing the effective density distributions with unit density lead to comparable estimates that were within 20% and 5% at engine idle and high thrust, respectively. These results could be used for the development of a robust method for sampling loss correction of the future PM emissions database from commercial aircraft engines.

  20. Biofuel Blending Impacts on Aircraft Engine Particle Emissions at Cruise Conditions

    NASA Astrophysics Data System (ADS)

    Moore, R.

    2015-12-01

    We present measurements of aerosol emissions indices and microphysical properties measured in-situ behind the CFM56-2-C1 engines of the NASA DC-8 aircraft during the 2014 Alternative Fuel Effects on Contrails and Cruise Emissions (ACCESS) project. Aircraft engine emissions can have a disproportionately large climatic impact since they are emitted high in the troposphere and in remote regions with otherwise low aerosol concentrations. This has motivated numerous past ground-based studies focused on quantifying the emissions indices of non-volatile and semi-volatile aerosol species, however, it is unclear the extent to which emissions on the ground translate to emissions at cruise conditions. In addition, the ability of engine-emitted aerosols to nucleate ice crystals and form linear contrails or contrail cirrus clouds remains poorly understood. To better understand these effects, two chase plane experiments were carried out in 2013 and 2014. Three different fuel types are discussed: a low-sulfur JP-8 fuel, a 50:50 blend of JP-8 and a camelina-based HEFA fuel, and the JP-8 fuel doped with sulfur. Emissions were sampled using a large number of aerosol and gas instruments integrated on HU-25 and Falcon 20 jets that were positioned in the DC-8 exhaust plume at approximately 50-500 m distance behind the engines. It was found that the biojet fuel blend substantially decreases the aerosol number and mass emissions indices, while the gas phase emission indices were similar across fuels. The magnitude of the effects of these fuel-induced changes of aerosol emissions and implications for future aviation biofuel blending impacts will be discussed.

  1. Aircraft Engine Emissions. [conference

    NASA Technical Reports Server (NTRS)

    1977-01-01

    A conference on a aircraft engine emissions was held to present the results of recent and current work. Such diverse areas as components, controls, energy efficient engine designs, and noise and pollution reduction are discussed.

  2. Assessment of Microphysical Models in the National Combustion Code (NCC) for Aircraft Particulate Emissions: Particle Loss in Sampling Lines

    NASA Technical Reports Server (NTRS)

    Wey, Thomas; Liu, Nan-Suey

    2008-01-01

    This paper at first describes the fluid network approach recently implemented into the National Combustion Code (NCC) for the simulation of transport of aerosols (volatile particles and soot) in the particulate sampling systems. This network-based approach complements the other two approaches already in the NCC, namely, the lower-order temporal approach and the CFD-based approach. The accuracy and the computational costs of these three approaches are then investigated in terms of their application to the prediction of particle losses through sample transmission and distribution lines. Their predictive capabilities are assessed by comparing the computed results with the experimental data. The present work will help establish standard methodologies for measuring the size and concentration of particles in high-temperature, high-velocity jet engine exhaust. Furthermore, the present work also represents the first step of a long term effort of validating physics-based tools for the prediction of aircraft particulate emissions.

  3. Collection and Analysis of Aircraft Emitted Particles

    NASA Technical Reports Server (NTRS)

    Wilson, James Charles

    1999-01-01

    The University of Denver Aerosol Group proposed to adapt an impactor system for the collection of particles emitted by aircraft. The collection substrates were electron microscope grids which were analyzed by Dr. Pat Sheridan using a transmission electron microscope. The impactor was flown in the SNIFF behind aircraft and engine emissions were sampled. This report details the results of that work.

  4. Measurement of In-Flight Aircraft Emissions

    NASA Technical Reports Server (NTRS)

    Sokoloski, M.; Arnold, C.; Rider, D.; Beer, R.; Worden, H.; Glavich, T.

    1995-01-01

    Aircraft engine emission and their chemical and physical evolution can be measured in flight using high resolution infrared spectroscopy. The Airborne Emission Spectrometer (AES), designed for remote measure- ments of atmosphere emissions from an airborne platform, is an ideal tool for the evaluation of aircraft emissions and their evolution. Capabilities of AES will be discussed. Ground data will be given.

  5. Using the NAME Lagrangian Particle Dispersion model, and aircraft measurements to assess the accuracy of trace gas emission inventories from the U.K.

    NASA Astrophysics Data System (ADS)

    O'Sullivan, D. A.; Harrison, M.; Ploson, D.; Oram, D.; Reeves, C.

    2007-12-01

    A top-down approach using a combination of aircraft data and atmospheric dispersion modelling has been used to estimate emissions for 24 halogenated trace gases from the United Kingdom. This has been done using data collected during AMPEP/FLUXEX, a U.K based measurement campaign which took place between April and September 2005. The primary objective relating to this work was to make direct airborne measurements of concentration enhancements within the boundary layer arising from anthropogenic pollution events, and then to use mass balance methods to determine an emission flux. This was done by analysing Whole Air Samples (WAS) collected in the boundary layer upwind and downwind of the UK at frequent intervals around the coast using the technique of gas chromatography mass spectrometry (GCMS). Emissions were then calculated using a simple box-model approach and also using NAME (Numerical Atmospheric-dispersion Modelling Environment) which is a Lagrangian particle model using 3 hourly 3D meteorology fields from the Met Office Unified Model. By using such an approach it is also possible to identify the most likely main source regions in the UK for the compounds measured. Among the trace gases studied are many which through their effects on stratospheric ozone, and their large radiative forcing have a direct impact on global climate such as CFC's 11, 12, 113 and 114, HCFC's 21, 22, 141b and 142b, HFC's 134a and 152a, methyl chloroform, methyl bromide and carbon tetrachloride. Also the emissions of some short lived gases with have direct effects on human health, such as tetrachloroethene, and trichloroethene, have been derived. The UK emissions estimates calculated from this experimental and modelling work are compared with bottom-up and other top-down emission inventories for the UK and Europe. It was found that the estimates from this study were often higher than those in bottom-up emission inventories derived from industry. In addition for a number of trace gases

  6. Environmental protection agency aircraft emissions standards

    NASA Technical Reports Server (NTRS)

    Kittredge, G. D.

    1977-01-01

    Emissions of air pollutants from aircraft were investigated in order to determine: (1) the extent to which such emissions affect air quality in air quality control regions throughout the United States; and (2) the technological feasibility of controlling such emissions. The basic information supporting the need for aircraft emissions standards is summarized. The EPA ambient air quality standards are presented. Only the primary (health related) standards are shown. Of the six pollutants, only the first three, carbon monoxide (CO), hydrocarbons (HC), and nitrogen oxides, are influenced significantly by aircraft.

  7. Aircraft Piston Engine Exhaust Emission Symposium

    NASA Technical Reports Server (NTRS)

    1976-01-01

    A 2-day symposium on the reduction of exhaust emissions from aircraft piston engines was held on September 14 and 15, 1976, at the Lewis Research Center in Cleveland, Ohio. Papers were presented by both government organizations and the general aviation industry on the status of government contracts, emission measurement problems, data reduction procedures, flight testing, and emission reduction techniques.

  8. CHARACTERIZATION OF ROTATING-WING AIRCRAFT EMISSIONS

    SciTech Connect

    Cheng, Mengdawn; Corporan, E.; Mahurin, Shannon Mark; DeWitt, M.

    2007-01-01

    Rotating-wing aircraft or helicopters are heavily used by the US military to transport cargo, troops and personnel, and perform combat missions. Similar helicopter engines (those from the Chinook helicopter, for example) are being used by civilian companies to lift and transport heavy loads. Emissions data for this type of engines are limited but are important for development and design of air quality control strategy for military installations and bases in the country that are surrounded by cities and metropolitan areas. Major gaseous, selected air toxics, and particulate emissions data from helicopters were measured for T700-GE-700 and T700-GE-701C running JP-8 and Fischer-Tropsch fuels in separate engine exhaust tests. Each engine-fuel combination test was run at three engine power levels from idle to maximum in sequence in each test in June 2007 at Hunter Army Airfield (HAAF) in Savannah, GA. The emissions from these engines were smaller than those (T33 and T56) tested earlier in terms of gas concentrations and particulate mass/number concentration. The mode diameter of a particle size distribution obtained from a test run throughout the whole campaign was smaller than 100 nm by a research-grade fast scanning mobility particle sizer, which was confirmed by a commercial scanning mobility particle sizer taking sample from a collocated position right at the engine exhaust exit plane. Use of FT fuel led to reduced particulate and gaseous emissions as compared to the use of JP-8 fuel on the same engine. Production of nanoparticles (with mobility diameter smaller than 20 nm) by the engine running on JP-8 fuel was clearly observed using a nano-DMA equipped scanning mobility particle sizer a few meters downstream from the engine exhaust plane. The production was proportional to the engine power setting, and likely to be caused by the sulfur content in the JP-8 fuel. Sulfate/sulfur data measured at the engine exhaust and the same downstream location supports such a

  9. Optical properties of urban aerosols, aircraft emissions, and heavy-duty diesel trucks using aerosol light extinction measurements by an Aerodyne Cavity Attenuated Phase Shift Particle Extinction Monitor (CAPS PMex)

    NASA Astrophysics Data System (ADS)

    Freedman, A.; Massoli, P.; Wood, E. C.; Allan, J. D.; Fortner, E.; Yu, Z.; Herndon, S. C.; Miake-Lye, R. C.; Onasch, T. B.

    2010-12-01

    We present results of optical property characterization of ambient particulate during several field deployments where measurements of aerosol light extinction (σep) are obtained using an Aerodyne Cavity Attenuated Phase Shift Particle Extinction Monitor (CAPS PMex). The CAPS PMex is able to provide extinction measurements with 3-σ detection limit of 3 Mm-1 for 1s integration time. The CAPS PMex (630 nm) is integrated in the Aerodyne Research, Inc. (ARI) mobile laboratory where a co-located Multi Angle Absorption Photometer (MAAP) provides particle light absorption coefficient at 632 nm. The combination of the CAPS with the MAAP data allows estimating the single scattering albedo (ω) of the ambient aerosol particles. The ARI mobile laboratory was deployed in winter 2010 at the Chicago O’Hare International Airport to measure gas phase and particulate emissions from different aircraft engines, and during summer 2010 in Oakland, CA, to characterize vehicular gaseous and particulate emissions (mainly exhaust from heavy-duty diesel trucks) from the Caldecott Tunnel. We provide estimates of black carbon emission factors from individual aircraft engines and diesel trucks, in addition to characterizing the optical properties of these ambient samples studying fleet-average emissions for both light-duty passenger vehicles and heavy-duty diesel trucks. Two CAPS PMex instruments (measuring σep at 630 and 532 nm) were also deployed during the CalNex 2010 study (May 14 - June 16) at the CalTech ground site in Pasadena, CA. During the same time, a photo-acoustic spectrometer (PAS, DMT) and an aethalometer instrument (Magee Sci.) measured particle light absorption of submicron aerosol particles from the same sample line as the CAPS PMex monitors. We combine these data to provide multi-wavelength ω trends for the one-month campaign. Our results show the high potential of the CAPS as light weight, compact instrument to perform precise and accurate σep measurements of

  10. Sulfuric Acid and Soot Particle Formation in Aircraft Exhaust

    NASA Technical Reports Server (NTRS)

    Pueschel, Rudolf F.; Verma, S.; Ferry, G. V.; Howard, S. D.; Vay, S.; Kinne, S. A.; Baumgardner, D.; Dermott, P.; Kreidenweis, S.; Goodman, J.; Gore, Waren J. Y. (Technical Monitor)

    1997-01-01

    A combination of CN counts, Ames wire impactor size analyses and optical particle counter data in aircraft exhaust results in a continuous particle size distribution between 0.01 micrometer and 1 micrometer particle radius sampled in the exhaust of a Boeing 757 research aircraft. The two orders of magnitude size range covered by the measurements correspond to 6-7 orders of magnitude particle concentration. CN counts and small particle wire impactor data determine a nucleation mode, composed of aircraft-emitted sulfuric acid aerosol, that contributes between 62% and 85% to the total aerosol surface area and between 31% and 34% to its volume. Soot aerosol comprises 0.5% of the surface area of the sulfuric acid aerosol. Emission indices are: EIH2SO4 = 0.05 g/kgFUEL and (0.2-0.5) g/kgFUEL (for 75 ppmm and 675 ppmm fuel-S, respectively), 2.5E4particles/kgFUEL (for 75 and 675 ppmm fuel-S). The sulfur (gas) to H2SO4 (particle) conversion efficiency is between 10% and 25%.

  11. Aviation Particle Emissions Workshop

    NASA Technical Reports Server (NTRS)

    Wey, Chowen C. (Editor)

    2004-01-01

    The Aviation Particle Emissions Workshop was held on November 18 19, 2003, in Cleveland, Ohio. It was sponsored by the National Aeronautic and Space Administration (NASA) under the Vehicle Systems Program (VSP) and the Ultra- Efficient Engine Technology (UEET) Project. The objectives were to build a sound foundation for a comprehensive particulate research roadmap and to provide a forum for discussion among U.S. stakeholders and researchers. Presentations included perspectives from the Federal Aviation Administration, the U.S. Environmental Protection Agency, NASA, and United States airports. There were five interactive technical sessions: sampling methodology, measurement methodology, particle modeling, database, inventory and test venue, and air quality. Each group presented technical issues which generated excellent discussion. The five session leads collaborated with their members to present summaries and conclusions to each content area.

  12. Commercial Aircraft Emission Scenario for 2020: Database Development and Analysis

    NASA Technical Reports Server (NTRS)

    Sutkus, Donald J., Jr.; Baughcum, Steven L.; DuBois, Douglas P.; Wey, Chowen C. (Technical Monitor)

    2003-01-01

    This report describes the development of a three-dimensional database of aircraft fuel use and emissions (NO(x), CO, and hydrocarbons) for the commercial aircraft fleet projected to 2020. Global totals of emissions and fuel burn for 2020 are compared to global totals from previous aircraft emission scenario calculations.

  13. High-speed Civil Transport Aircraft Emissions

    NASA Technical Reports Server (NTRS)

    Miake-Lye, Richard C.; Matulaitis, J. A.; Krause, F. H.; Dodds, Willard J.; Albers, Martin; Hourmouziadis, J.; Hasel, K. L.; Lohmann, R. P.; Stander, C.; Gerstle, John H.

    1992-01-01

    Estimates are given for the emissions from a proposed high speed civil transport (HSCT). This advanced technology supersonic aircraft would fly in the lower stratosphere at a speed of roughly Mach 1.6 to 3.2 (470 to 950 m/sec or 920 to 1850 knots). Because it would fly in the stratosphere at an altitude in the range of 15 to 23 km commensurate with its design speed, its exhaust effluents could perturb the chemical balance in the upper atmosphere. The first step in determining the nature and magnitude of any chemical changes in the atmosphere resulting from these proposed aircraft is to identify and quantify the chemically important species they emit. Relevant earlier work is summarized, dating back to the Climatic Impact Assessment Program of the early 1970s and current propulsion research efforts. Estimates are provided of the chemical composition of an HSCT's exhaust, and these emission indices are presented. Other aircraft emissions that are not due to combustion processes are also summarized; these emissions are found to be much smaller than the exhaust emissions. Future advances in propulsion technology, in experimental measurement techniques, and in understanding upper atmospheric chemistry may affect these estimates of the amounts of trace exhaust species or their relative importance.

  14. Aircraft hydrocarbon emissions at Oakland International Airport.

    PubMed

    Herndon, Scott C; Wood, Ezra C; Northway, Megan J; Miake-Lye, Richard; Thornhill, Lee; Beyersdorf, Andreas; Anderson, Bruce E; Dowlin, Renee; Dodds, Willard; Knighton, W Berk

    2009-03-15

    To help airports improve emission inventory data, speciated hydrocarbon emission indices have been measured from in-use commercial, airfreight, and general aviation aircraft at Oakland International Airport. The compounds reported here include formaldehyde, acetaldehyde, ethene, propene, and benzene. At idle, the magnitude of hydrocarbon emission indices was variable and reflected differences in engine technology, actual throttle setting, and ambient temperature. Scaling the measured emission indices to the simultaneously measured formaldehyde (HCHO) emission index eliminated most of the observed variability. This result supports a uniform hydrocarbon emissions profile across engine types when the engine is operating near idle, which can greatly simplify how speciated hydrocarbons are handled in emission inventories. The magnitude of the measured hydrocarbon emission index observed in these measurements (ambient temperature range 12-22 degrees C) is a factor of 1.5-2.2 times larger than the certification benchmarks. Using estimates of operational fuel flow rates at idle, this analysis suggests that current emission inventories at the temperatures encountered at this airport underestimate hydrocarbon emissions from the idle phase of operation by 16-45%.

  15. Primary VOC emissions from Commercial Aircraft Jet Engines

    NASA Astrophysics Data System (ADS)

    Kilic, Dogushan; Huang, Rujin; Slowik, Jay; Brem, Benjamin; Durdina, Lukas; Rindlisbacher, Theo; Baltensperger, Urs; Prevot, Andre

    2014-05-01

    Air traffic is growing continuously [1]. The increasing number of airplanes leads to an increase of aviation emissions giving rise to environmental concerns globally by high altitude emissions and, locally on air quality at the ground level [2]. The overall impact of aviation emissions on the environment is likely to increase when the growing air transportation trend [2] is considered. The Aviation Particle Regulatory Instrumentation Demonstration Experiment (APRIDE)-5 campaign took place at Zurich Airport in 2013. In this campaign, aircraft exhaust is sampled during engine acceptance tests after engine overhaul at the facilities of SR Technics. Direct sampling from the engine core is made possible due to the unique fixed installation of a retractable sampling probe and the use of a standardized sampling system designed for the new particulate matter regulation in development for aircraft engines. Many of the gas-phase aircraft emissions, e.g. CO2, NOX, CO, SO2, hydrocarbons, and volatile organic compounds (VOC) were detected by the instruments in use. This study, part of the APRIDE-5 campaign, focuses on the primary VOC emissions in order to produce emission factors of VOC species for varying engine operating conditions which are the surrogates for the flight cycles. Previously, aircraft plumes were sampled in order to quantify VOCs by a proton transfer reaction quadrupole mass spectrometer (PTR-MS) [3]. This earlier study provided a preliminary knowledge on the emission of species such as methanol, acetaldehyde, acetone, benzene and toluene by varying engine thrust levels. The new setup was (i) designed to sample from the diluted engine exhaust and the new tool and (ii) used a high resolution time of flight PTR-MS with higher accuracy for many new species, therefore providing a more detailed and accurate inventory. We will present the emission factors for species that were quantified previously, as well as for many additional VOCs detected during the campaign

  16. Influence of Ohio River Valley Emissions on Fine Particle Sulfate Measured from Aircraft over Large Regions of the Eastern United States and Canada during INTEX-NA

    NASA Technical Reports Server (NTRS)

    Hennigan, Christopher J.; Sandholm, Scott; Kim, Saewung; Stickel, Robert E.; Huey, L. Gregory; Weber, Rodney J.

    2006-01-01

    Aircraft measurements of fine inorganic aerosol composition were made with a particle-into-liquid sampler coupled to dual ion chromatographs (PILS-IC) as part of the NASA INTEX-NA study. The sampling campaign, which lasted from 1 July to 14 August 2004, centered over the eastern United States and Canada and showed that sulfate was the dominant inorganic species measured. The highest sulfate concentrations were observed at altitudes below 2 km, and back trajectory analyses showed a distinct difference between air masses that had or had not intercepted the Ohio River valley (ORV) region. Air masses encountered below 2 km with a history over the ORV had sulfate concentrations that were higher by a factor of 3.2 and total sulfur (S) concentrations higher by 2.5. The study's highest sulfate concentrations were found in these air masses. The sulfur of the ORV air masses was also more processed with a mean sulfate to total sulfur molar ratio of 0.5 compared to 0.3 in non-ORV measurements. Results from a second, independent trajectory model agreed well with those from the primary analysis. These ORV-influenced air masses were encountered on multiple days and were widely spread across the eastern United States and western Atlantic region.

  17. A plume capture technique for the remote characterization of aircraft engine emissions.

    PubMed

    Johnson, G R; Mazaheri, M; Ristovski, Z D; Morawska, L

    2008-07-01

    A technique for capturing and analyzing plumes from unmodified aircraft or other combustion sources under real world conditions is described and applied to the task of characterizing plumes from commercial aircraft during the taxiing phase of the Landing/Take-Off (LTO) cycle. The method utilizes a Plume Capture and Analysis System (PCAS) mounted in a four-wheel drive vehicle which is positioned in the airfield 60 to 180 m downwind of aircraft operations. The approach offers low test turnaround times with the ability to complete careful measurements of particle and gaseous emission factors and sequentially scanned particle size distributions without distortion due to plume concentration fluctuations. These measurements can be performed for individual aircraft movements at five minute intervals. A Plume Capture Device (PCD) collected samples of the naturally diluted plume in a 200 L conductive membrane conforming to a defined shape. Samples from over 60 aircraft movements were collected and analyzed in situ for particulate and gaseous concentrations and for particle size distribution using a Scanning Particle Mobility Sizer (SMPS). Emission factors are derived for particle number, NO(x), and PM2.5 for a widely used commercial aircraft type, Boeing 737 airframes with predominantly CFM56 class engines, during taxiing. The practical advantages of the PCAS include the capacity to perform well targeted and controlled emission factor and size distribution measurements using instrumentation with varying response times within an airport facility, in close proximity to aircraft during their normal operations.

  18. Global Civil Aviation Black Carbon Particle Mass and Number Emissions

    NASA Astrophysics Data System (ADS)

    Stettler, M. E. J.

    2015-12-01

    Black carbon (BC) is a product of incomplete combustion emitted by aircraft engines. In the atmosphere, BC particles strongly absorb incoming solar radiation and influence cloud formation processes leading to highly uncertain, but likely net positive warming of the earth's atmosphere. At cruise altitude, BC particle number emissions can influence the concentration of ice nuclei that can lead to contrail formation, with significant and highly uncertainty climate impacts. BC particles emitted by aircraft engines also degrade air quality in the vicinity of airports and globally. A significant contribution to the uncertainty in environmental impacts of aviation BC emissions is the uncertainty in emissions inventories. Previous work has shown that global aviation BC mass emissions are likely to have been underestimated by a factor of three. In this study, we present an updated global BC particle number inventory and evaluate parameters that contribute to uncertainty using global sensitivity analysis techniques. The method of calculating particle number from mass utilises a description of the mobility of fractal aggregates and uses the geometric mean diameter, geometric standard deviation, mass-mobility exponent, primary particle diameter and material density to relate the particle number concentration to the total mass concentration. Model results show good agreement with existing measurements of aircraft BC emissions at ground level and at cruise altitude. It is hoped that the results of this study can be applied to estimate direct and indirect climate impacts of aviation BC emissions in future studies.

  19. Evaluation of Methods for the Determination of Black Carbon Emissions from an Aircraft Gas Turbine Engine

    EPA Science Inventory

    The emissions from aircraft gas turbine engines consist of nanometer size black carbon (BC) particles plus gas-phase sulfur and organic compounds which undergo gas-to-particle conversion downstream of the engine as the plume cools and dilutes. In this study, four BC measurement ...

  20. Primary particles in ship emissions

    NASA Astrophysics Data System (ADS)

    Fridell, Erik; Steen, Erica; Peterson, Kjell

    There is not much data available regarding particle emissions from ships. In this study the size distributions of particles in ship exhaust from three different ships in normal operational conditions were studied using a cascade impactor. The ships were equipped with slow- or medium-speed main engines and medium-speed auxiliary engines. The fuel was residual oil except for the auxiliary engines on one ship which used marine diesel. Large emissions and a dependence of the sulfur content in the fuel were observed. High amounts of relatively large particles (around 8 μm) were observed. These are attributed to re-entrained soot particles from walls in the engine systems. A strong variation between different ships was observed for the particle-size distribution and for the dependence on engine load. The particle emissions were found to be reduced to about half, over the whole size range, by an SCR system. The total particle emission, measured after dilution, varied between 0.3 and 3 g kW h -1 depending on load, fuel and engine.

  1. Counting Particles Emitted by Stratospheric Aircraft and Measuring Size of Particles Emitted by Stratospheric Aircraft

    NASA Technical Reports Server (NTRS)

    Wilson, James Charles

    1994-01-01

    There were two principal objectives of the cooperative agreement between NASA and the University of Denver. The first goal was to modify the design of the ER-2 condensation nuclei counter (CNC) so that the effective lower detection limit would be improved at high altitudes. This improvement was sought because, in the instrument used prior to 1993, diffusion losses prevented the smallest detectable particles from reaching the detection volume of the instrument during operation at low pressure. Therefore, in spite of the sensor's ability to detect particles as small as 0.008 microns in diameter, many of these particles were lost in transport to the sensing region and were not counted. Most of the particles emitted by aircraft are smaller than 0.1 micron in diameter. At the start date of this work, May 1990, continuous sizing techniques available on the ER-2 were only capable of detecting particles larger than 0.17 micron. Thus, the second objective of this work was to evaluate candidate sizing techniques in an effort to gain additional information concerning the size of particles emitted by aircraft.

  2. Direct carbon dioxide emissions from civil aircraft

    NASA Astrophysics Data System (ADS)

    Grote, Matt; Williams, Ian; Preston, John

    2014-10-01

    Global airlines consume over 5 million barrels of oil per day, and the resulting carbon dioxide (CO2) emitted by aircraft engines is of concern. This article provides a contemporary review of the literature associated with the measures available to the civil aviation industry for mitigating CO2 emissions from aircraft. The measures are addressed under two categories - policy and legal-related measures, and technological and operational measures. Results of the review are used to develop several insights into the challenges faced. The analysis shows that forecasts for strong growth in air-traffic will result in civil aviation becoming an increasingly significant contributor to anthropogenic CO2 emissions. Some mitigation-measures can be left to market-forces as the key-driver for implementation because they directly reduce airlines' fuel consumption, and their impact on reducing fuel-costs will be welcomed by the industry. Other mitigation-measures cannot be left to market-forces. Speed of implementation and stringency of these measures will not be satisfactorily resolved unattended, and the current global regulatory-framework does not provide the necessary strength of stewardship. A global regulator with ‘teeth' needs to be established, but investing such a body with the appropriate level of authority requires securing an international agreement which history would suggest is going to be very difficult. If all mitigation-measures are successfully implemented, it is still likely that traffic growth-rates will continue to out-pace emissions reduction-rates. Therefore, to achieve an overall reduction in CO2 emissions, behaviour change will be necessary to reduce demand for air-travel. However, reducing demand will be strongly resisted by all stakeholders in the industry; and the ticket price-increases necessary to induce the required reduction in traffic growth-rates place a monetary-value on CO2 emissions of approximately 7-100 times greater than other common

  3. A Comprehensive Program for Measurement of Military Aircraft Emissions

    SciTech Connect

    Cheng, Mengdawn

    2009-11-01

    Emissions of gases and particulate matter by military aircraft were characterized inplume by 'extractive' and 'optical remote-sensing (ORS)' technologies. Non-volatile particle size distribution, number and mass concentrations were measured with good precision and reproducibly. Time-integrated particulate filter samples were collected and analyzed for smoke number, elemental composition, carbon contents, and sulfate. Observed at EEP the geometric mean diameter (as measured by the mobility diameter) generally increased as the engine power setting increased, which is consistent with downstream observations. The modal diameters at the downstream locations are larger than that at EEP at the same engine power level. The results indicate that engine particles were processed by condensation, for example, leading to particle growth in-plume. Elemental analysis indicated little metals were present in the exhaust, while most of the exhaust materials in the particulate phase were carbon and sulfate (in the JP-8 fuel). CO, CO{sub 2}, NO, NO{sub 2}, SO{sub 2}, HCHO, ethylene, acetylene, propylene, and alkanes were measured. The last five species were most noticeable under engine idle condition. The levels of hydrocarbons emitted at high engine power level were generally below the detection limits. ORS techniques yielded real-time gaseous measurement, but the same techniques could not be extended directly to ultrafine particles found in all engine exhausts. The results validated sampling methodology and measurement techniques used for non-volatile particulate aircraft emissions, which also highlighted the needs for further research on sampling and measurement for volatile particulate matter and semi-volatile species in the engine exhaust especially at the low engine power setting.

  4. Calculation of odour emissions from aircraft engines at Copenhagen Airport.

    PubMed

    Winther, Morten; Kousgaard, Uffe; Oxbøl, Arne

    2006-07-31

    In a new approach the odour emissions from aircraft engines at Copenhagen Airport are calculated using actual fuel flow and emission measurements (one main engine and one APU: Auxiliary Power Unit), odour panel results, engine specific data and aircraft operational data for seven busy days. The calculation principle assumes a linear relation between odour and HC emissions. Using a digitalisation of the aircraft movements in the airport area, the results are depicted on grid maps, clearly reflecting aircraft operational statistics as single flights or total activity during a whole day. The results clearly reflect the short-term temporal fluctuations of the emissions of odour (and exhaust gases). Aircraft operating at low engine thrust (taxiing, queuing and landing) have a total odour emission share of almost 98%, whereas the shares for the take off/climb out phases (2%) and APU usage (0.5%) are only marginal. In most hours of the day, the largest odour emissions occur, when the total amount of fuel burned during idle is high. However, significantly higher HC emissions for one specific engine cause considerable amounts of odour emissions during limited time periods. The experimentally derived odour emission factor of 57 OU/mg HC is within the range of 23 and 110 OU/mg HC used in other airport odour studies. The distribution of odour emission results between aircraft operational phases also correspond very well with the results for these other studies. The present study uses measurement data for a representative engine. However, the uncertainties become large when the experimental data is used to estimate the odour emissions for all aircraft engines. More experimental data is needed to increase inventory accuracy, and in terms of completeness it is recommended to make odour emission estimates also for engine start and the fuelling of aircraft at Copenhagen Airport in the future.

  5. 78 FR 65554 - Exhaust Emission Standards for New Aircraft Turbine Engines and Identification Plate for Aircraft...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-11-01

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF TRANSPORTATION Federal Aviation Administration 14 CFR Parts 34 and 45 RIN 2120-AK15 Exhaust Emission Standards for New Aircraft Turbine Engines and Identification Plate for Aircraft Engines Correction In rule document 2013-24712, appearing on pages 63015-63017...

  6. Aircraft emission measurements by remote sensing methodologies at airports

    NASA Astrophysics Data System (ADS)

    Schäfer, Klaus; Jahn, Carsten; Sturm, Peter; Lechner, Bernhard; Bacher, Michael

    The emission indices of aircraft engine exhausts from measurements taken under operating conditions, to calculate precisely the emission inventories of airports, are not available up to now. To determine these data, measurement campaigns were performed on idling aircraft at major European airports using non-intrusive spectroscopic methods like Fourier transform infrared spectrometry and differential optical absorption spectroscopy. Emission indices for CO and NO x were calculated and compared to the values given in the International Civil Aviation Organisation (ICAO) database. The emission index for CO for 36 different aircraft engine types and for NO x (24 different engine types) were determined. It was shown that for idling aircraft, CO emissions are underestimated using the ICAO database. The emission indices for NO x determined in this work are lower than given in the ICAO database. In addition, a high variance of emission indices in each aircraft family and from engine to engine of the same engine type was found. During the same measurement campaigns, the emission indices for CO and NO of eight different types of auxilliary power units were investigated.

  7. Characterization of particulate matter and gaseous emissions of a C-130H aircraft.

    PubMed

    Corporan, Edwin; Quick, Adam; DeWitt, Matthew J

    2008-04-01

    The gaseous and nonvolatile particulate matter (PM) emissions of two T56-A-15 turboprop engines of a C-130H aircraft stationed at the 123rd Airlift Wing in the Kentucky Air National Guard were characterized. The emissions campaign supports the Strategic Environmental Research and Development Program (SERDP) project WP-1401 to determine emissions factors from military aircraft. The purpose of the project is to develop a comprehensive emissions measurement program using both conventional and advanced techniques to determine emissions factors of pollutants, and to investigate the spatial and temporal evolutions of the exhaust plumes from fixed and rotating wing military aircraft. Standard practices for the measurement of gaseous emissions from aircraft have been well established; however, there is no certified methodology for the measurement of aircraft PM emissions. In this study, several conventional instruments were used to physically characterize and quantify the PM emissions from the two turboprop engines. Emissions samples were extracted from the engine exit plane and transported to the analytical instrumentation via heated lines. Multiple sampling probes were used to assess the spatial variation and obtain a representative average of the engine emissions. Particle concentrations, size distributions, and mass emissions were measured using commercially available aerosol instruments. Engine smoke numbers were determined using established Society of Automotive Engineers (SAE) practices, and gaseous species were quantified via a Fourier-transform infrared-based gas analyzer. The engines were tested at five power settings, from idle to take-off power, to cover a wide range of operating conditions. Average corrected particle numbers (PNs) of (6.4-14.3) x 10(7) particles per cm3 and PN emission indices (EI) from 3.5 x 10(15) to 10.0 x 10(15) particles per kg-fuel were observed. The highest PN EI were observed for the idle power conditions. The mean particle diameter

  8. Commercial aircraft engine emissions characterization of in-use aircraft at Hartsfield-Jackson Atlanta International Airport.

    PubMed

    Herndon, Scott C; Jayne, John T; Lobo, Prem; Onasch, Timothy B; Fleming, Gregg; Hagen, Donald E; Whitefield, Philip D; Miake-Lye, Richard C

    2008-03-15

    The emissions from in-use commercial aircraft engines have been analyzed for selected gas-phase species and particulate characteristics using continuous extractive sampling 1-2 min downwind from operational taxi- and runways at Hartsfield-Jackson Atlanta International Airport. Using the aircraft tail numbers, 376 plumes were associated with specific engine models. In general, for takeoff plumes, the measured NOx emission index is lower (approximately 18%) than that predicted by engine certification data corrected for ambient conditions. These results are an in-service observation of the practice of "reduced thrust takeoff". The CO emission index observed in ground idle plumes was greater (up to 100%) than predicted by engine certification data for the 7% thrust condition. Significant differences are observed in the emissions of black carbon and particle number among different engine models/technologies. The presence of a mode at approximately 65 nm (mobility diameter) associated with takeoff plumes and a smaller mode at approximately 25 nm associated with idle plumes has been observed. An anticorrelation between particle mass loading and particle number concentration is observed.

  9. Analyses of Scenarios for Past and Possible Future Aircraft Emissions

    NASA Technical Reports Server (NTRS)

    Wuebbles, Donald J.; Patten, Kenneth O.; Rahmes, Tim

    1997-01-01

    This project contains several components to work with the NASA AEAP program in better definition of scenarios for aircraft emissions and in determining the sensitivity of the atmosphere to such emissions. Under this project, Don Wuebbles continues as chair of the Operations and Emissions Scenarios Committee for AEAP. We are also coordinating with the International Civil Aviation Organization (ICAO) to ensure the highest quality possible in the emissions scenarios promoted by the Emissions Scenarios committee. We continue to help coordination of NASA AEAP with international activities. This includes work with ICAO towards international analysis of aircraft emissions inventories; performing analyses to compare and evaluate databases of aircraft emissions developed for NASA and by various international groups and from these analyses, develop guidelines for future emissions scenarios development. Special sensitivity analyses, using our two-dimensional chemical-transport model of the global troposphere and stratosphere, have been used to determine potential sensitivity of further enhancements that could be made to emissions scenarios development. The latter studies are to be used in prioritizing further emissions scenario development.

  10. Estimation of glycol air emissions from aircraft deicing

    SciTech Connect

    McCready, D.

    1998-12-31

    Ethylene glycol (EG) and propylene glycol (PG)-based fluids (collectively referred to as glycol) are recognized as effective in removing and preventing snow and ice contamination on aircraft before take-off. Although much work has been done to develop an understanding of the potential impact of spent fluid run-off to water bodies, little attention has been paid to the potential environmental impact, if any, due to air emissions. In order to determine potential impact from air emissions, it is necessary to develop a protocol for estimating the glycol emissions during deicing operations. This paper presents two approaches for estimating glycol air emissions from aircraft deicing fluids (ADF) and aircraft anti-icing fluids (AAF). The first simple approach is based on emission factors and the quantity of fluid applied. The second approach estimates emissions for a typical deicing event based on site-specific parameters. Sample calculations are presented. The predicted glycol evaporation rates are quite low. Calculated emissions from ethylene glycol-based fluids are lower than emissions from PG-based fluids. The calculated air emissions for a typical event are less than a pound for EG-based fluids. The emission rate from PG-based fluids can be two times greater.

  11. Assessing the Impact of Aircraft Emissions on the Stratosphere

    NASA Technical Reports Server (NTRS)

    Kawa, S. R.; Anderson, D. E.

    1999-01-01

    For the past decade, the NASA Atmospheric Effects of Aviation Project (AEAP) has been the U.S. focal point for research on aircraft effects. In conjunction with U.S. basic research programs, AEAP and concurrent European research programs have driven remarkable progress reports released in 1999 [IPCC, 1999; Kawa et al., 1999]. The former report primarily focuses on aircraft effects in the upper troposphere, with some discussion on stratospheric impacts. The latter report focuses entirely on the stratosphere. The current status of research regarding aviation effects on stratospheric ozone and climate, as embodied by the findings of these reports, is reviewed. The following topics are addressed: Aircraft Emissions, Pollution Transport, Atmospheric Chemistry, Polar Processes, Climate Impacts of Supersonic Aircraft, Subsonic Aircraft Effect on the Stratosphere, Calculations of the Supersonic Impact on Ozone and Sensitivity to Input Conditions.

  12. Experimental Measurements of the Effects of Photo-chemical Oxidation on Aerosol Emissions in Aircraft Exhaust

    NASA Astrophysics Data System (ADS)

    Miracolo, M. A.; Presto, A. A.; Hennigan, C. J.; Nguyen, N.; Ranjan, M.; Reeder, A.; Lipsky, E.; Donahue, N. M.; Robinson, A. L.

    2009-12-01

    Many military and commercial airfields are located in non-attainment areas for particulate matter (PM2.5), but the contribution of emissions from in-use aircraft to local and regional PM2.5 concentrations is uncertain. In collaboration with the Pennsylvania Air National Guard 171st Air Refueling Wing, the Carnegie Mellon University (CMU) Mobile Laboratory was deployed to measure fresh and aged emissions from a CFM56-2B1 gas-turbine engine mounted on a KC-135 Stratotanker airframe. The CFM-56 family of engine powers many different types of military and civilian aircraft, including the Boeing 737 and several Airbus models. It is one of the most widely deployed models of engines in the world. The goal of this work was to measure the gas-particle partitioning of the fresh emissions at atmospherically relevant conditions and to investigate the effect of atmospheric oxidation on aerosol loadings as the emissions age. Emissions were sampled from an inlet installed one meter downstream of the engine exit plane and transferred into a portable smog chamber via a heated inlet line. Separate experiments were conducted at different engine loads ranging from ground idle to take-off rated thrust. During each experiment, some diluted exhaust was added to the chamber and the volatility of the fresh emissions was then characterized using a thermodenuder. After this characterization, the chamber was exposed to either ambient sunlight or UV lights to initiate photochemical oxidation, which produced secondary aerosol and ozone. A suite of gas and particle-phase instrumentation was used to characterize the evolution of the gas and particle-phase emissions, including an aerosol mass spectrometer (AMS) to measure particle size and composition distributions. Fresh emissions of fine particles varied with engine load with peak emission factors at low and high loads. At high engine loads, the fresh emissions were dominated by black carbon; at low loads volatile organic carbon emissions were

  13. Pollution Emission Analysis of Selected Air Force Aircraft

    DTIC Science & Technology

    1974-04-29

    percent for large non-combat tranaport engines) are proposed. Eraoke numbers wlilch will ensure Invisible aircraft smoke plumes are specified. The...standards are being violated, as well as being significant sources of smoke , ,••(3) that maintenance of the national ambient sir quality BlSndards...and reduced impact of smoke emission requires that air- craft and aircraft engines be Bubjected to a program of control compatible with their

  14. Measurements of aircraft emissions indices at airports passive remote sensing

    NASA Astrophysics Data System (ADS)

    Schaefer, Klaus; Jahn, Carsten; Sturm, Peter J.; Lechner, Bernhard; Bacher, Michael

    2003-04-01

    The emission indices of aircraft engine exhausts to calculate precisely the emissions inventories of airports are not available up to now from measurements taken under operating conditions. To determine these data no installations nearby or behind the aircraft are possible at airports. That's why measurements by FTIR emission spectrometry were performed by the IMK-IFU with a spectrometer installed in a van and with total measurement time at one thrust level of about 1 minute to determine CO, NO and CO2. The FTIR instrument telescope was aligned to the engine nozzle exit of standing aircraft. A DOAS and a FTIR spectrometer with globar were used for simultaneous open-path measurements of NO, NO2, CO, CO2 and speciated hydrocarbons behind the aircraft by the TUG-VKMB. Measurement results at the airports Frankfurt/Main, London-Heathrow and Vienna are presented. The methods are evaluated by comparing CO emission indices from passive measurements with open-path data. The measured emission indices of CO show slightly higher values than the International Civil Aviation Organisation data sheets but less values for NOx emissions. A fruitful co-operation with the airlines AUA, BA and DLH as well as the airport authorities in Vienna and London-Heathrow supported this work which is financed from EC.

  15. Propulsion Investigation for Zero and Near-Zero Emissions Aircraft

    NASA Technical Reports Server (NTRS)

    Snyder, Christopher A.; Berton, Jeffrey J.; Brown, Gerald v.; Dolce, James L.; Dravid, Marayan V.; Eichenberg, Dennis J.; Freeh, Joshua E.; Gallo, Christopher A.; Jones, Scott M.; Kundu, Krishna P.; Marek, Cecil J.; Millis, Marc G.; Murthy, Pappu L.; Roach, Timothy M.; Smith, Timothy D.; Stefko, George L.; Sullivan, Roy M.; Tornabene, Robert T.; Geiselhat, Karl A.; Kascak, Albert F.

    2009-01-01

    As world emissions are further scrutinized to identify areas for improvement, aviation s contribution to the problem can no longer be ignored. Previous studies for zero or near-zero emissions aircraft suggest aircraft and propulsion system sizes that would perform propulsion system and subsystems layout and propellant tankage analyses to verify the weight-scaling relationships. These efforts could be used to identify and guide subsequent work on systems and subsystems to achieve viable aircraft system emissions goals. Previous work quickly focused these efforts on propulsion systems for 70- and 100-passenger aircraft. Propulsion systems modeled included hydrogen-fueled gas turbines and fuel cells; some preliminary estimates combined these two systems. Hydrogen gas-turbine engines, with advanced combustor technology, could realize significant reductions in nitrogen emissions. Hydrogen fuel cell propulsion systems were further laid out, and more detailed analysis identified systems needed and weight goals for a viable overall system weight. Results show significant, necessary reductions in overall weight, predominantly on the fuel cell stack, and power management and distribution subsystems to achieve reasonable overall aircraft sizes and weights. Preliminary conceptual analyses for a combination of gas-turbine and fuel cell systems were also performed, and further studies were recommended. Using gas-turbine engines combined with fuel cell systems can reduce the fuel cell propulsion system weight, but at higher fuel usage than using the fuel cell only.

  16. Measurements of Nucleation-Mode Particle Size Distributions in Aircraft Plumes during SULFUR 6

    NASA Technical Reports Server (NTRS)

    Brock, Charles A.; Bradford, Deborah G.

    1999-01-01

    This report summarizes the participation of the University of Denver in an airborne measurement program, SULFUR 6, which was undertaken in late September and early October of 1998 by the Deutsches Zentrum fur Luft und Raumfahrt (DLR). Scientific findings from two papers that have been published or accepted and from one manuscript that is in preparation are presented. The SULFUR 6 experiment was designed to investigate the emissions from subsonic aircraft to constrain calculations of possible atmospheric chemical and climatic effects. The University of Denver effort contributed toward the following SULFUR 6 goals: (1) To investigate the relationship between fuel sulfur content (FSC--mass of sulfur per mass of fuel) and particle number and mass emission index (El--quantity emitted per kg of fuel burned); (2) To provide upper and lower limits for the mass conversion efficiency (nu) of fuel sulfur to gaseous and particulate sulfuric acid; (3) To constrain models of volatile particle nucleation and growth by measuring the particle size distribution between 3 and 100 nm at aircraft plume ages ranging from 10(exp -1) to 10(exp 3) s; (4) To determine microphysical and optical properties and bulk chemical composition of soot particles in aircraft exhaust; and (5) To investigate the differences in particle properties between aircraft plumes in contrail and non-contrail situations. The experiment focused on emissions from the ATTAS research aircraft (a well characterized, but older technology turbojet) and from an in-service Boeing 737-300 aircraft provided by Lufthansa, with modem, high-bypass turbofan engines. Measurements were made from the DLR Dassault Falcon 900 aircraft, a modified business jet. The Atmospheric Effects of Aviation Program (AEAP) provided funding to operate an instrument, the nucleation-mode aerosol size spectrometer (N-MASS), during the SULFUR 6 campaign and to analyze the data. The N-MASS was developed at the University of Denver with the support of

  17. ICOARE: Impacts on Climate and Ozone from Aircraft and Rocket Emissions

    NASA Astrophysics Data System (ADS)

    Toohey, D. W.; Ross, M.

    2009-12-01

    This presentation will provide an overview of an Earth Venture proposal for a series of in situ measurements in the exhaust plumes of aircraft and rockets with the following objectives: to obtain information that is critical for reducing the uncertainties in assessments (e.g., WMO and IPCC) of the impacts of aviation and aerospace activities on regional and global climate; to assess the viability of a climate engineering scheme that employs injection of reflective particles into the lower stratosphere; and to initiate the development of an operational modeling tool that can be used by the aviation and aerospace industries to guide design of new transporation systems that minimize the impact on Earth’s climate. The ICOARE mission will deploy instruments to measure water vapor, ice water content, tracers, reactive species, particles, and radiation fields on a high-altitude aircraft to characterize the variability of water vapor in aircraft and rocket contrails, determine accurate emission indices for initialization of plume-wake and regional scale models, investigate the microphysical properties of cirrus particles in and out of aircraft corridors, and examine the light scattering properties of contrail ice crystals and small alumina particles. Focused campaigns will be timed to occur around the launch schedules of a variety of rocket types in order to characterize the range of emissions from the current launch suite. There will be special emphasis on characterizing the emissions from rockets employing new propellants, in particular those that may produce soot and nitrogen oxides. Observations in aircraft exhaust, and examinations of cirrus cloud properties and persistent contrails, will occur on flights that are not dedicated to studies of rockets (e.g., test, transit, and rocket-scrub flights). ICOARE will offer a unique opportunities for training students and postdoctorates, especially those from underrepresented groups, in areas of project management, logistics

  18. Atmospheric cosmic rays and solar energetic particles at aircraft altitudes.

    PubMed

    O'Brien, K; Friedberg, W; Sauer, H H; Smart, D F

    1996-01-01

    Galactic cosmic rays, which are thought to be produced and accelerated by a variety of mechanisms in the Milky Way galaxy, interact with the solar wind, the earth's magnetic field, and its atmosphere to produce hadron, lepton, and photon fields at aircraft altitudes that are quite unlike anything produced in the laboratory. The energy spectra of these secondary particles extend from the lowest possible energy to energies over an EeV. In addition to cosmic rays, energetic particles, generated on the sun by solar flares or coronal mass ejections, bombard the earth from time to time. These particles, while less energetic than cosmic rays, also produce radiation fields at aircraft altitudes which have qualitatively the same properties as cosmic rays. The authors have calculated atmospheric cosmic-ray angular fluxes, spectra, scalar fluxes, and ionization, and compared them with experimental data. Agreement with these data is seen to be good. These data have been used to calculate equivalent doses in a simplified human phantom at aircraft altitudes and the estimated health risks to aircraft crews. The authors have also calculated the radiation doses from several large solar energetic particle events (known as GLEs, or Ground Level Events), which took place in 1989, including the very large event known as GLE 42, which took place on September 29th and 30th of that year. The spectra incident on the atmosphere were determined assuming diffusive shock theory. Unfortunately, there are essentially no experimental data with which to compare these calculations.

  19. TCM aircraft piston engine emission reduction program

    NASA Technical Reports Server (NTRS)

    Rezy, B. J.

    1976-01-01

    The technology necessary to safely reduce general aviation piston engine exhaust emissions to meet the EPA 1980 Emission Standards with minimum adverse effects on cost, weight, fuel economy, and performance was demonstrated. A screening and assessment of promising emission reduction concepts was provided, and the preliminary design and development of those concepts was established. A system analysis study and a decision making procedure were used by TCM to evaluate, trade off, and rank the candidate concepts from a list of 14 alternatives. Cost, emissions, and 13 other design criteria considerations were defined and traded off against each candidate concept to establish its merit and emission reduction usefulness. A computer program was used to aid the evaluators in making the final choice of three concepts.

  20. Alternative Fuels Tests on a C-17 Aircraft: Emissions Characteristics

    DTIC Science & Technology

    2010-12-01

    control number. PLEASE DO NOT RETURN YOUR FORM TO THE ABOVE ADDRESS. 1. REPORT DATE (DD-MM-YY) 2. REPORT TYPE 3 . DATES COVERED (From - To) December...Emissions were collected from engine 3 of the parked aircraft operated on conventional JP-8 and 50/50 blends of JP-8 and a beef tallow-derived HRJ, and a... 3 2.1.2 Gaseous Emissions.............................................................................. 5

  1. USAF Aircraft Engine Emission Goals: A Critical Review.

    DTIC Science & Technology

    1979-09-01

    dif- ficult to obtain. Combustion product gases at the exhaust plane are extremely reactive and at high temperature; consequently, much of the CO and...19. KEY WORDS (Continue on reverse side if necessary and identify by block number) J Pollution Abatement Exhaust Emissions Combustion Aircraft...The USAF must continue basic research in areas of combustion , smoke formation, etc. it - -W: (7) Variability of emissions is an area where more

  2. Chemical characterization of freshly emitted particulate matter from aircraft exhaust using single particle mass spectrometry

    NASA Astrophysics Data System (ADS)

    Abegglen, Manuel; Brem, B. T.; Ellenrieder, M.; Durdina, L.; Rindlisbacher, T.; Wang, J.; Lohmann, U.; Sierau, B.

    2016-06-01

    Non-volatile aircraft engine emissions are an important anthropogenic source of soot particles in the upper troposphere and in the vicinity of airports. They influence climate and contribute to global warming. In addition, they impact air quality and thus human health and the environment. The chemical composition of non-volatile particulate matter emission from aircraft engines was investigated using single particle time-of-flight mass spectrometry. The exhaust from three different aircraft engines was sampled and analyzed. The soot particulate matter was sampled directly behind the turbine in a test cell at Zurich Airport. Single particle analyses will focus on metallic compounds. The particles analyzed herein represent a subset of the emissions composed of the largest particles with a mobility diameter >100 nm due to instrumental restrictions. A vast majority of the analyzed particles was shown to contain elemental carbon, and depending on the engine and the applied thrust the elemental carbon to total carbon ratio ranged from 83% to 99%. The detected metallic compounds were all internally mixed with the soot particles. The most abundant metals in the exhaust were Cr, Fe, Mo, Na, Ca and Al; V, Ba, Co, Cu, Ni, Pb, Mg, Mn, Si, Ti and Zr were also detected. We further investigated potential sources of the ATOFMS-detected metallic compounds using Inductively Coupled Plasma Mass Spectrometry. The potential sources considered were kerosene, engine lubrication oil and abrasion from engine wearing components. An unambiguous source apportionment was not possible because most metallic compounds were detected in several of the analyzed sources.

  3. Continental anthropogenic primary particle number emissions

    NASA Astrophysics Data System (ADS)

    Paasonen, Pauli; Kupiainen, Kaarle; Klimont, Zbigniew; Visschedijk, Antoon; Denier van der Gon, Hugo A. C.; Amann, Markus

    2016-06-01

    Atmospheric aerosol particle number concentrations impact our climate and health in ways different from those of aerosol mass concentrations. However, the global, current and future anthropogenic particle number emissions and their size distributions are so far poorly known. In this article, we present the implementation of particle number emission factors and the related size distributions in the GAINS (Greenhouse Gas-Air Pollution Interactions and Synergies) model. This implementation allows for global estimates of particle number emissions under different future scenarios, consistent with emissions of other pollutants and greenhouse gases. In addition to determining the general particulate number emissions, we also describe a method to estimate the number size distributions of the emitted black carbon particles. The first results show that the sources dominating the particle number emissions are different to those dominating the mass emissions. The major global number source is road traffic, followed by residential combustion of biofuels and coal (especially in China, India and Africa), coke production (Russia and China), and industrial combustion and processes. The size distributions of emitted particles differ across the world, depending on the main sources: in regions dominated by traffic and industry, the number size distribution of emissions peaks in diameters range from 20 to 50 nm, whereas in regions with intensive biofuel combustion and/or agricultural waste burning, the emissions of particles with diameters around 100 nm are dominant. In the baseline (current legislation) scenario, the particle number emissions in Europe, Northern and Southern Americas, Australia, and China decrease until 2030, whereas especially for India, a strong increase is estimated. The results of this study provide input for modelling of the future changes in aerosol-cloud interactions as well as particle number related adverse health effects, e.g. in response to tightening

  4. Characterization of chemical and particulate emissions from aircraft engines

    NASA Astrophysics Data System (ADS)

    Agrawal, Harshit; Sawant, Aniket A.; Jansen, Karel; Wayne Miller, J.; Cocker, David R.

    2008-06-01

    This paper presents a series of measurements from four on-wing, commercial aircraft engines, including two newer CFM56-7 engines and two earlier CFM56-3 engines. Samples were collected from each engine using a probe positioned behind the exhaust nozzle of the aircraft, chocked on a concrete testing pad. The emission factors for particulate matter mass, elemental and organic carbon, carbonyls, polycyclic aromatic hydrocarbons, n-alkanes, dioxins, metals and ions are reported for four different engine power setting modes. The emissions indices of particulate matter, elemental and organic carbon are highly power dependent for these engines. Particulate matter emission indices (g kg-1 fuel) are found to increase from 1.1E-02 to 2.05E-01 with increase in power from idle to 85%. The elemental carbon to organic carbon varies from 0.5 to 3.8 with change in power from idle to 85%. The carbonyl emissions are dominated by formaldehyde. The emission index of formaldehyde ranges from 2.3E-01 to 4.8E-01 g kg-1 fuel. The distribution of metals depends on the difference in the various engines. The dioxin emissions from the aircraft engines are observed to be below detection limit.

  5. Regulations for Greenhouse Gas Emissions from Aircraft

    EPA Pesticide Factsheets

    EPA and the National Highway Traffic Safety Administration (NHTSA) are taking coordinated steps to enable the production of a new generation of clean vehicles, through reduced greenhouse gas (GHG) emissions and improved fuel use from onroad vehicles.

  6. Aircraft emissions characterization: F101 and F110 engines. Final report Jun 87-Mar 89

    SciTech Connect

    Spicer, C.W.; Holdren, M.W.; Smith, D.L.; Miller, S.E.; Smith, R.N.

    1990-03-01

    Assessment of the environmental impact of aircraft operations is required by Air Force regulations. This program was undertaken to quantify gaseous and particulate emissions associated with two Air Force turbine engines (F101 and F110). The emissions tests were carried out using a test cell at Tinker AFB, Oklahoma City, OK. All tests employed JP-4 as the fuel, and fuel samples were characterized by standard tests and analyzed for composition. Emissions were measured at five power settings for each engine. Detailed organic composition, CO, CO2, NO, NOx, smoke emissions, particle concentration, and particle size distribution were measured. A multiport sampling rake was used to sample the exhaust, and heated Teflon tubing was used to transfer exhaust to the monitoring instrumentation. Measured and calculated fuel/air ratios were compared to assure representative sampling of the exhaust.

  7. Aircraft measurements of microwave emission from Arctic Sea ice

    USGS Publications Warehouse

    Wilheit, T.; Nordberg, W.; Blinn, J.; Campbell, W.; Edgerton, A.

    1971-01-01

    Measurements of the microwave emission from Arctic Sea ice were made with aircraft at 8 wavelengths ranging from 0.510 to 2.81 cm. The expected contrast in emissivities between ice and water was observed at all wavelengths. Distributions of sea ice and open water were mapped from altitudes up to 11 km in the presence of dense cloud cover. Different forms of ice also exhibited strong contrasts in emissivity. Emissivity differences of up to 0.2 were observed between two types of ice at the 0.811-cm wavelength. The higher emissivity ice type is tentatively identified as having been formed more recently than the lower emissivity ice. ?? 1971.

  8. Year 2015 Aircraft Emission Scenario for Scheduled Air Traffic

    NASA Technical Reports Server (NTRS)

    Baughcum, Steven L.; Sutkus, Donald J.; Henderson, Stephen C.

    1998-01-01

    This report describes the development of a three-dimensional scenario of aircraft fuel burn and emissions (fuel burned, NOx, CO, and hydrocarbons)for projected year 2015 scheduled air traffic. These emission inventories are available for use by atmospheric scientists conducting the Atmospheric Effects of Aviation Project (AEAP) modeling studies. Fuel burned and emissions of nitrogen oxides (NOx as NO2), carbon monoxides, and hydrocarbons have been calculated on a 1 degree latitude x 1 degree longitude x 1 kilometer altitude grid and delivered to NASA as electronic files.

  9. QCGAT aircraft/engine design for reduced noise and emissions

    NASA Technical Reports Server (NTRS)

    Lanson, L.; Terrill, K. M.

    1980-01-01

    The high bypass ratio QCGAT engine played an important role in shaping the aircraft design. The aircraft which evolved is a sleek, advanced design, six-place aircraft with 3538 kg (7,800 lb) maximum gross weight. It offers a 2778 kilometer (1500 nautical mile) range with cruise speed of 0.5 Mach number and will take-off and land on the vast majority of general aviation airfields. Advanced features include broad application of composite materials and a supercritical wing design with winglets. Full-span fowler flaps were introduced to improve landing capability. Engines are fuselage-mounted with inlets over the wing to provide shielding of fan noise by the wing surfaces. The design objectives, noise, and emission considerations, engine cycle and engine description are discussed as well as specific design features.

  10. Exhaust emissions reduction for intermittent combustion aircraft engines

    NASA Technical Reports Server (NTRS)

    Rezy, B. J.; Stuckas, K. J.; Tucker, J. R.; Meyers, J. E.

    1982-01-01

    Three concepts which, to an aircraft piston engine, provide reductions in exhaust emissions of hydrocarbons and carbon monoxide while simultaneously improving fuel economy. The three chosen concepts, (1) an improved fuel injection system, (2) an improved cooling cylinder head, and (3) exhaust air injection, when combined, show a synergistic relationship in achieving these goals. In addition, the benefits of variable ignition timing were explored and both dynamometer and flight testing of the final engine configuration were accomplished.

  11. Exhaust emission reduction for intermittent combustion aircraft engines

    NASA Technical Reports Server (NTRS)

    Moffett, R. N.

    1979-01-01

    Three concepts for optimizing the performance, increasing the fuel economy, and reducing exhaust emission of the piston aircraft engine were investigated. High energy-multiple spark discharge and spark plug tip penetration, ultrasonic fuel vaporization, and variable valve timing were evaluated individually. Ultrasonic fuel vaporization did not demonstrate sufficient improvement in distribution to offset the performance loss caused by the additional manifold restriction. High energy ignition and revised spark plug tip location provided no change in performance or emissions. Variable valve timing provided some performance benefit; however, even greater performance improvement was obtained through induction system tuning which could be accomplished with far less complexity.

  12. Chromate content versus particle size for aircraft paints.

    PubMed

    LaPuma, Peter T; Rhodes, Brian S

    2002-12-01

    Many industries rely on the corrosion inhibiting properties of chromate-containing primer paints to protect metal from oxidation. However, chromate contains hexavalent chromium (Cr(6+)), a known human carcinogen. The concentration of Cr(6+) as a function of paint particle size has important implications to worker health and environmental release from paint facilities. This research examines Cr(6+) content as a function of particle size for three types of aircraft primer paints: solvent-based epoxy-polyamide, water-based epoxy-polyamide, and solvent-based polyurethane. Cascade impactors were used to collect and separate paint particles based on their aerodynamic diameter, from 0.7 to 34.1 microm. The mass of the dry paint collected at each stage was determined and an atomic absorption spectrometer was used to analyze for Cr(6+) content. For all three paints, particles less than 7.0 microm contained disproportionately less Cr(6+) per mass of dry paint than larger particles, and the Cr(6+)concentration decreased substantially as particle size decreased. The smallest particles, 0.7 to 1.0 microm, contained approximately 10% of the Cr(6+) content, per mass of dry paint, compared to particles larger than 7.0 microm. The paint gun settings of air to paint ratio was found to have no influence on the Cr(6+) bias.

  13. Reductions in aircraft particulate emissions due to the use of Fischer-Tropsch fuels

    NASA Astrophysics Data System (ADS)

    Beyersdorf, A. J.; Timko, M. T.; Ziemba, L. D.; Bulzan, D.; Corporan, E.; Herndon, S. C.; Howard, R.; Miake-Lye, R.; Thornhill, K. L.; Winstead, E.; Wey, C.; Yu, Z.; Anderson, B. E.

    2013-06-01

    The use of alternative fuels for aviation is likely to increase due to concerns over fuel security, price stability and the sustainability of fuel sources. Concurrent reductions in particulate emissions from these alternative fuels are expected because of changes in fuel composition including reduced sulfur and aromatic content. The NASA Alternative Aviation Fuel Experiment (AAFEX) was conducted in January-February 2009 to investigate the effects of synthetic fuels on gas-phase and particulate emissions. Standard petroleum JP-8 fuel, pure synthetic fuels produced from natural gas and coal feedstocks using the Fischer-Tropsch (FT) process, and 50% blends of both fuels were tested in the CFM-56 engines on a DC-8 aircraft. To examine plume chemistry and particle evolution with time, samples were drawn from inlet probes positioned 1, 30, and 145 m downstream of the aircraft engines. No significant alteration to engine performance was measured when burning the alternative fuels. However, leaks in the aircraft fuel system were detected when operated with the pure FT fuels as a result of the absence of aromatic compounds in the fuel. Dramatic reductions in soot emissions were measured for both the pure FT fuels (reductions of 84% averaged over all powers) and blended fuels (64%) relative to the JP-8 baseline with the largest reductions at idle conditions. The alternative fuels also produced smaller soot (e.g. at 85% power, volume mean diameters were reduced from 78 nm for JP-8 to 51 nm for the FT fuel), which may reduce their ability to act as cloud condensation nuclei (CCN). The reductions in particulate emissions are expected for all alternative fuels with similar reductions in fuel sulfur and aromatic content regardless of the feedstock. As the plume cools downwind of the engine, nucleation-mode aerosols form. For the pure FT fuels, reductions (94% averaged over all powers) in downwind particle number emissions were similar to those measured at the exhaust plane (84

  14. Air-sampling inlet contamination by aircraft emissions on the NASA CV-990 aircraft

    NASA Technical Reports Server (NTRS)

    Condon, E. P.; Vedder, J. F.

    1984-01-01

    Results of an experimental investigation of the contamination of air sampling inlets by aircraft emissions from the NASA CV-990 research aircraft are presented. This four-engine jet aircraft is a NASA facility used for many different atmospheric and meteorological experiments, as well as for developing spacecraft instrumentation for remote measurements. Our investigations were performed to provide information on which to base the selection of sampling locations for a series of multi-instrument missions for measuring tropospheric trace gases. The major source of contamination is the exhaust from the jet engines, which generate many of the same gases that are of interest in atmospheric chemistry, as well as other gases that may interfere with sampling measurements. The engine exhaust contains these gases in mixing ratios many orders of magnitude greater than those that occur in the clean atmosphere which the missions seek to quantify. Pressurized samples of air were collected simultaneously from a scoop located forward of the engines to represent clean air and from other multiport scoops at various aft positions on the aircraft. The air samples were analyzed in the laboratory by gas chromatography for carbon monoxide, an abundant combustion by-product. Data are presented for various scoop locations under various flight conditions.

  15. Modeling Aircraft Emissions for Regional-scale Air Quality: Adapting a New Global Aircraft Emissions Database for the U.S

    NASA Astrophysics Data System (ADS)

    Arunachalam, S.; Baek, B. H.; Vennam, P. L.; Woody, M. C.; Omary, M.; Binkowski, F.; Fleming, G.

    2012-12-01

    Commercial aircraft emit substantial amounts of pollutants during their complete activity cycle that ranges from landing-and-takeoff (LTO) at airports to cruising in upper elevations of the atmosphere, and affect both air quality and climate. Since these emissions are not uniformly emitted over the earth, and have substantial temporal and spatial variability, it is vital to accurately evaluate and quantify the relative impacts of aviation emissions on ambient air quality. Regional-scale air quality modeling applications do not routinely include these aircraft emissions from all cycles. Federal Aviation Administration (FAA) has developed the Aviation Environmental Design Tool (AEDT), a software system that dynamically models aircraft performance in space and time to calculate fuel burn and emissions from gate-to-gate for all commercial aviation activity from all airports globally. To process in-flight aircraft emissions and to provide a realistic representation of these for treatment in grid-based air quality models, we have developed an interface processor called AEDTproc that accurately distributes full-flight chorded emissions in time and space to create gridded, hourly model-ready emissions input data. Unlike the traditional emissions modeling approach of treating aviation emissions as ground-level sources or processing emissions only from the LTO cycles in regional-scale air quality studies, AEDTproc distributes chorded inventories of aircraft emissions during LTO cycles and cruise activities into a time-variant 3-D gridded structure. We will present results of processed 2006 global emissions from AEDT over a continental U.S. modeling domain to support a national-scale air quality assessment of the incremental impacts of aircraft emissions on surface air quality. This includes about 13.6 million flights within the U.S. out of 31.2 million flights globally. We will focus on assessing spatio-temporal variability of these commercial aircraft emissions, and

  16. Counting particles emitted by stratospheric aircraft and measuring size of particles emitted by stratospheric aircraft

    NASA Technical Reports Server (NTRS)

    Wilson, James Charles

    1994-01-01

    The ER-2 condensation nuclei counter (CNC) has been modified to reduce the diffusive losses of particles within the instrument. These changes have been successful in improving the counting efficiency of small particles at low pressures. Two techniques for measuring the size distributions of particles with diameters less than 0.17 micrometers have been evaluated. Both of these methods, the differential mobility analyzer (DMA) and the diffusion battery, have fundamental problems that limit their usefulness for stratospheric applications. We cannot recommend either for this application. Newly developed, alternative methods for measuring small particles include inertial separation with a low-loss critical orifice and thin-plate impactor device. This technique is now used to collect particles in the multisample aerosol collector housed in the ER-2 CNC-2, and shows some promise for particle size measurements when coupled with a CNC as a counting device. The modified focused-cavity aerosol spectrometer (FCAS) can determine the size distribution of particles with ambient diameters as small as about 0.07 micrometers. Data from this instrument indicates the presence of a nuclei mode when CNC-2 indicates high concentrations of particles, but cannot resolve important parameters of the distribution.

  17. Sulfuric Acid and Soot Particles in Aircraft Exhaust

    NASA Technical Reports Server (NTRS)

    Pueschel, Rudolf F.; Verma, S.; Ferry, G. V.; Goodman, J.; Strawa, A. W.; Gore, Warren J. Y. (Technical Monitor)

    1997-01-01

    Aircraft have become the fastest, fairly convenient and, in most cases of long-distance travel, most economical mode of travel. This is reflected in the increase of commercial air traffic at a rate of 6% per year since 1978. Future annual growth rates of passenger miles of 4% for domestic and 6% for international routes are projected. A still larger annual increase of 8.5% is expected for the Asia/Pacific region. To meet that growth, Boeing predicts the addition of 15,900 new aircraft to the world's fleets, valued at more than $1.1 trillion, within the next 20 years. The largest concern of environmental consequences of aircraft emissions deals with ozone (O3), because: (1) the O3 layer protects the blaspheme from short-ultraviolet radiation that can cause damage to human, animal and plant life, and possibly affect agricultural production and the marine food chain; (2) O3 is important for the production of the hydroxyl radical (OH) which, in turn, is responsible for the destruction of other greenhouse gases, e.g., methane (CH4) and for the removal of other pollutants, and (3) O3 is a greenhouse gas. Additional information is contained in the original extended abstract.

  18. Military Aircraft Emissions Research - Case of Hercules Cargo Plane (C-130H) Emissions

    SciTech Connect

    Cheng, Mengdawn; Corporan, E.; DeWitt, M.; Harris, B.; Hashmonay, R.; Holdren, M.; Kaganan, R.; Spicer, C.

    2007-01-01

    Tactical airlifter like C-130H has been in use for more than 50 years, and is expected to serve for many years to come. However, the emission characteristics data of the aircraft are scarce. To increase our understanding of turboprop engine emissions, emissions from a military C-130H cargo aircraft were characterized in field conditions in the fall of 2005. Particulate and gaseous pollutants were measured by conventional and advanced instrumentation platforms that were built with in-situ extractive or remote optical sensing technologies. The measurements performed at the C-130H engine exhaust exit showed increased levels of emissions as the engine power setting increased. In contrast, there was no such a relationship found for the C-130H emitted particulate matter (as a function of engine power setting) measured at about 15-m downstream of the engine exhaust plane. The emitted gaseous species measured at both locations were, however, proportional to the engine power setting and comparable (at both locations) when corrected for ambient dilution indicating the lack of particulate emission-power setting relationship at the far field is unique. The result clearly indicates that the aircraft emission factor or index for particulate matter cannot be experimentally determined at a downstream location away from the exhaust exit and has to be determined right at the engine exhaust plane. Emission indices that are needed for air quality modeling will be presented.

  19. 77 FR 65823 - Control of Air Pollution From Aircraft and Aircraft Engines; Emission Standards and Test Procedures

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-10-31

    ... From the Federal Register Online via the Government Publishing Office ENVIRONMENTAL PROTECTION AGENCY 40 CFR Parts 87 RIN 2060-AO70 Control of Air Pollution From Aircraft and Aircraft Engines; Emission Standards and Test Procedures Correction In rule document 2012-13828 appearing on pages...

  20. 77 FR 36341 - Control of Air Pollution From Aircraft and Aircraft Engines; Emission Standards and Test Procedures

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-06-18

    ... nitrogen (NO X ), compliance flexibilities, and other regulatory requirements for aircraft turbofan or... Exposure to Ozone, PM and NO X a. Deposition of Nitrogen b. Visibility Effects c. Plant and Ecosystem... nitrogen (NO X ) emission standards for aircraft engines with rated thrusts greater than 26.7 kN...

  1. Study of air emissions related to aircraft deicing

    SciTech Connect

    Zarubiak, D.C.Z.; DeToro, J.A.; Menon, R.P.

    1997-12-31

    This paper outlines the results of a study that was conducted by Trinity Consultants Incorporated (Trinity) to estimate the airborne emissions of glycol from Type 1 Deicer fluid and potential exposure of ground personnel during routine deicing of aircraft. The study involved the experimental measurement of Type 1 Deicer fluid vapor emissions by Southern Research Institute (SRI, Research Triangle Park, NC). An open path Fourier Transform Infrared (FTIR) spectroscopic technique developed by SRI was used during a simulated airplane deicing event. The emissions measurement data are analyzed to obtain appropriate emission rates for an atmospheric dispersion modeling analysis. The modeled gaseous Type 1 Deicer fluid concentrations are determined from calculated emission rates and selected meteorological conditions. A propylene glycol (PG)-based Type 1 Deicer fluid was used. In order to examine the effects of the assumptions that are made for the development of the emission quantification and dispersion modeling methodologies, various scenarios are evaluated. A parametric analysis evaluates the effect of variations in the following parameters on the results of the study: glycol concentrations in deicing fluids, error limits of emission measurements, emission source heights, evaporation rate for various wind speeds, wind directions over typical physical layouts, and background (ambient) Type 1 Deicer fluid concentrations. The emissions for an EG based Type 1 Deicing fluid are expected to be between 80 and 85% of the reported data. In general, the model shows the region of maximum concentrations is located between 20 and 50 meters downwind from the trailing edge of the wing. This range is consistent with experimental findings. Depending on the specific modeled scenarios, maximum glycol concentrations are found to generally range between 50 and 500 milligrams per cubic meter.

  2. Particle emission from artificial cometary materials

    NASA Technical Reports Server (NTRS)

    Koelzer, Gabriele; Kochan, Hermann; Thiel, Klaus

    1992-01-01

    During KOSI (comet simulation) experiments, mineral-ice mixtures are observed in simulated space conditions. Emission of ice-/dust particles from the sample surface is observed by means of different devices. The particle trajectories are recorded with a video system. In the following analysis we extracted the parameters: particle count rate, spatial distribution of starting points on the sample surface, and elevation angle and particle velocity at distances up to 5 cm from the sample surface. Different kinds of detectors are mounted on a frame in front of the sample to register the emitted particles and to collect their dust residues. By means of these instruments the particle count rates, the particle sizes and the composition of the particles can be correlated. The results are related to the gas flux density and the temperature on the sample surface during the insolation period. The particle emission is interpreted in terms of phenomena on the sample surface, e.g., formation of a dust mantle.

  3. The role of ions in the formation and evolution of particles in aircraft plumes

    NASA Astrophysics Data System (ADS)

    Yu, Fangqun; Turco, Richard P.

    We consider the effects on aircraft plume microphysics of ions generated by chemiionization processes within the engine combustors. Ions provide centers around which molecular clusters rapidly coalesce, thus promoting the formation of electrically charged sulfuric acid/water aerosols. The resulting charged micro-particles exhibit enhanced growth due to condensation and coagulation aided by electrostatic effects. Simulations with a plume microphysics code show that volatile particles observed behind aircraft may be explained by such processes, as long as initial ion concentrations in the exhaust exceed ˜108/cm³. This analysis also suggests that the primary emissions of sulfuric acid (plus sulfur trioxide) should amount to at least 20-30% of the fuel sulfur to explain the observed number of volatile particles >9 nm in diameter. Ionized plume simulations reveal a distinct bimodal aerosol distribution, in which an “ion” mode constitutes the larger “activated” volatile sulfuric acid particles, while a smaller “neutral” mode comprises the residual slowly-growing neutral molecular clusters formed in the highly supersaturated region of the plume.

  4. Mechanism of light-particle emission

    SciTech Connect

    Nagamiya, S.

    1982-02-01

    A general overview of the field of high-energy nuclear collisions studied from light particle spectra, pions, kaons, lambdas, protons, deuterons, and light composite fragments is given. Specifically, the basic reaction mechanism that determines the main features of particle emission such as the energy and angular distributions, the multiplicity, the production rate, the projectile and target mass dependences, the beam-energy dependences, etc. are discussed. Very general features of high-energy nuclear collisions are described. The major question is what characterizes these collisions. Proton emission is discussed since the proton is the dominant particle emitted at a large angle. The mechanism of composite-fragment formation is discussed. Also pion production and strange particle production are considered.

  5. Aircraft emission impacts in a neighborhood adjacent to a general aviation airport in southern California.

    PubMed

    Hu, Shishan; Fruin, Scott; Kozawa, Kathleen; Mara, Steve; Winer, Arthur M; Paulson, Suzanne E

    2009-11-01

    Real time air pollutant concentrations were measured downwind of Santa Monica Airport (SMA), using an electric vehicle mobile platform equipped with fast response instruments in spring and summer of 2008. SMA is a general aviation airport operated for private aircraft and corporate jets in Los Angeles County, California. An impact area of elevated ultrafine particle (UFP) concentrations was observed extending beyond 660 m downwind and 250 m perpendicular to the wind on the downwind side of SMA. Aircraft operations resulted in average UFP concentrations elevated by factors of 10 and 2.5 at 100 and 660 m downwind, respectively, over background levels. The long downwind impact distance (i.e., compared to nearby freeways at the same time of day) is likely primarily due to the large volumes of aircraft emissions containing higher initial concentrations of UFP than on-road vehicles. Aircraft did not appreciably elevate average levels of black carbon (BC), particle-bound polycyclic aromatic hydrocarbons (PB-PAH), although spikes in concentration of these pollutants were observed associated with jet takeoffs. Jet departures resulted in peak 60-s average concentrations of up to 2.2 x 10(6) cm(-3), 440 ng m(-3), and 30 microg m(-3) for UFP, PB-PAH, and BC, respectively, 100 m downwind of the takeoff area. These peak levels were elevated by factors of 440, 90, and 100 compared to background concentrations. Peak UFP concentrations were reasonably correlated (r(2) = 0.62) with fuel consumption rates associated with aircraft departures, estimated from aircraft weights and acceleration rates. UFP concentrations remained elevated for extended periods associated particularly with jet departures, but also with jet taxi and idle, and operations of propeller aircraft. UFP measured downwind of SMA had a median mode of about 11 nm (electric mobility diameter), which was about half of the 22 nm median mode associated with UFP from heavy duty diesel trucks. The observation of highly

  6. Costs of mitigating CO2 emissions from passenger aircraft

    NASA Astrophysics Data System (ADS)

    Schäfer, Andreas W.; Evans, Antony D.; Reynolds, Tom G.; Dray, Lynnette

    2016-04-01

    In response to strong growth in air transportation CO2 emissions, governments and industry began to explore and implement mitigation measures and targets in the early 2000s. However, in the absence of rigorous analyses assessing the costs for mitigating CO2 emissions, these policies could be economically wasteful. Here we identify the cost-effectiveness of CO2 emission reductions from narrow-body aircraft, the workhorse of passenger air transportation. We find that in the US, a combination of fuel burn reduction strategies could reduce the 2012 level of life cycle CO2 emissions per passenger kilometre by around 2% per year to mid-century. These intensity reductions would occur at zero marginal costs for oil prices between US$50-100 per barrel. Even larger reductions are possible, but could impose extra costs and require the adoption of biomass-based synthetic fuels. The extent to which these intensity reductions will translate into absolute emissions reductions will depend on fleet growth.

  7. Simulating the global transport of nitrogen oxides emissions from aircraft

    NASA Astrophysics Data System (ADS)

    Sausen, R.; Köhler, I.

    1994-05-01

    With the atmosphere general circulation model ECHAM the passive transport of NOx emitted from global subsonic air traffic and the NOx concentration change due to these emissions are investigated. The source of NOx is prescribed according to an aircraft emission data base. The sink of NOx is parameterized as an exponential decay process with globally constant lifetime. Simulations in perpetual January and July modes are performed. Both the resulting mean and the standard deviation of the NOx mass mixing ratio are analysed. In January horizontal dispersion is more pronounced and vertical mixing is smaller than in July. In both cases the resulting quasi-stationary fields of the mass mixing ratio display a pronounced zonal asymmetry. The variability accounts up to 30% of the mean field.

  8. Aircraft gas turbine low-power emissions reduction technology program

    NASA Technical Reports Server (NTRS)

    Dodds, W. J.; Gleason, C. C.; Bahr, D. W.

    1978-01-01

    Advanced aircraft turbine engine combustor technology was used to reduce low-power emissions of carbon monoxide and unburned hydrocarbons to levels significantly lower than those which were achieved with current technology. Three combustor design concepts, which were designated as the hot-wall liner concept, the recuperative-cooled liner concept, and the catalyst converter concept, were evaluated in a series of CF6-50 engine size 40 degree-sector combustor rig tests. Twenty-one configurations were tested at operating conditions spanning the design condition which was an inlet temperature and pressure of 422 K and 304 kPa, a reference velocity of 23 m/s and a fuel-air-ration of 10.5 g/kg. At the design condition typical of aircraft turbine engine ground idle operation, the best configurations of all three concepts met the stringent emission goals which were 10, 1, and 4 g/kg for CO, HC, and Nox, respectively.

  9. A Comprehensive Program for Measurements of Military Aircraft Emissions

    DTIC Science & Technology

    2009-11-30

    XRF X - Ray Fluorescence x LIST OF KEYWORDS Air Toxics Engine Emission Extractive Sampling Fastscan...TEFLO® for particulate metal content by X - Ray Fluorescence ( XRF ), while the other set of filters are quartz for measurement of particulate carbon...Particulate sulfur was analyzed after the campaign in a laboratory by using an X - Ray fluorescence ( XRF ) spectrometer on particles collected on

  10. PM emissions measurements of in-service commercial aircraft engines during the Delta-Atlanta Hartsfield Study

    NASA Astrophysics Data System (ADS)

    Lobo, Prem; Hagen, Donald E.; Whitefield, Philip D.; Raper, David

    2015-03-01

    This paper describes the results of the physical characterization of aircraft engine PM emission measurements conducted during the Delta-Atlanta Hartsfield Study at the Hartsfield-Jackson Atlanta International Airport. Engine exit plane PM emissions were sampled from on-wing engines on several in-service commercial transport aircraft from the fleet of Delta Airlines. The size distributions were lognormal in nature with a single mode. The geometric mean diameter was found to increase with increasing engine thrust, ranging from 15 nm at idle to 40 nm at takeoff. PM number- and mass-based emission indices were observed to be higher at the idle conditions (4% and 7%), lowest at 15%-30% thrust, and then increase with increasing thrust. Emissions measurements were also conducted during an advected plume study where over 300 exhaust plumes generated by a broad mix of commercial transports were sampled 100-350 m downwind from aircraft operational runways during normal airport operations. The range of values measured at take-off for the different engine types in terms of PM number-based emission index was between 7 × 1015-9 × 1017 particles/kg fuel burned, and that for PM mass-based emission index was 0.1-0.6 g/kg fuel burned. PM characteristics of aircraft engine specific exhaust were found to evolve over time as the exhaust plume expands, dilutes with ambient air, and cools. The data from these measurements will enhance the emissions inventory development for a subset of engines operating in the commercial fleet and improve/validate current environmental impact predictive tools with real world aircraft engine specific PM emissions inputs.

  11. Identical particle model on biophoton emission

    NASA Astrophysics Data System (ADS)

    Liu, T. C.; Liu, Songhao; Popp, Fritz A.; Tang, Ao-Qing

    1996-09-01

    Biophoton emission (PE) method is a non-invasive way revealing biophysical interactions in living tissues. Since its mechanism is not very clear, its acceptance is limited. Gu has presented the quantum theory on biophoton emission according to the Dicke model. However, the Dicke model does not apply to biological system. In this paper, we studied PE by using the identical particle model, the interaction of identical particles by quantum chemistry, as well as the transition of the system interacting with radiation by the time quantum theory on radiation-matter interaction put forward by the first author and his cooperators. It was shown that the identical particles form coherent states, the photon emission probability of the superradiant state is a liner function of N and N2, and the one of the subradiant state is zero. In other words, the photon emission intensity represents the coherent states of the identical particle system. The linear relationship of N and N2 agrees with the PE experiment results on early drosophila embryos. The research on the cell division cycle showed that the superradiant states correspond to the late S phase. This is why PE can be used to differentiate human tumor tissues from normal ones. We also studied induced PE.

  12. RFID Transponders' RF Emissions in Aircraft Communication and Navigation Radio Bands

    NASA Technical Reports Server (NTRS)

    Nguyen, Truong X.; Ely, Jay J.; Koppen Sandra V.; Fersch, Mariatheresa S.

    2008-01-01

    Radiated emission data in aircraft communication and navigation bands are presented for several active radio frequency identification (RFID) tags. The individual tags are different in design, operation and transmitting frequencies. The process for measuring the tags emissions in a reverberation chamber is discussed. Measurement issues dealing with tag interrogation, low level measurement in the presence of strong transmissions, and tags low duty factors are discussed. The results show strong emissions, far exceeding aircraft emission limits and can be of potential interference risks.

  13. Gaseous Emissions from Aircraft Engines. A Handbook for the Calculation of Emission Indexes and Gaseous Emissions from Aircraft Engines

    DTIC Science & Technology

    1987-09-01

    corresponded to intervals of stable engine operation, as specified by the operators of the engine. Each laboratory reported emission indexes for the read ...period. The test established 50 read periods for gaseous emissions. Tabl, 5-1 gives the emission indexes at idle, high idle, approach, cruise and...emission indexes from a T58-GE-8F engine Test Cell - 12 Location - Naval Air Rework Facility, North Island IDLE Date Time Reading Prior Emission index

  14. Proposed Rule and Related Materials for Control of Emissions of Air Pollution From Nonroad Diesel Engines Control of Air Pollution From Aircraft and Aircraft Engines; Proposed Emission Standards and Test Procedures

    EPA Pesticide Factsheets

    Proposed Rule and Related Materials for Control of Emissions of Air Pollution From Nonroad Diesel Engines Control of Air Pollution From Aircraft and Aircraft Engines; Proposed Emission Standards and Test Procedures

  15. Aircraft

    DTIC Science & Technology

    2002-01-01

    Company, Washington, DC Boeing Commercial Aircraft Division, Seattle, WA and Long Beach, CA Boeing Military Aircraft and Missile Division, St. Louis, MO and... aircraft ; military fixed-wing aircraft ; rotorcraft (helicopters and tiltrotor aircraft ); and aircraft jet engines. Two companies dominate the commercial... aircraft business, Boeing and Airbus. Four companies dominate the military fixed-wing market, Boeing, Lockheed Martin, BAE Systems, and European

  16. Impact of aircraft NO x emission on NO x and ozone over China

    NASA Astrophysics Data System (ADS)

    Liu, Yu; Isaksen, I. S. A.; Sundet, J. K.; Zhou, Xiuji; Ma, Jianzhong

    2003-07-01

    A three-dimensional global chemistry transport model (OSLO CTM2) is used to investigate the impact of subsonic aircraft NO x emission on NO x and ozone over China in terms of a year 2000 scenario of subsonic aircraft NO x emission. The results show that subsonic aircraft NO x emission significantly affects northern China, which makes NO x at 250 hPa increase by about 50 pptv with the highest percentage of 60% in January, and leading to an ozone increase of 8 ppbv with 5% relative change in April. The NO x increase is mainly attributed to the transport process, but ozone increase is produced by the chemical process. The NO x increases by less than 10 pptv by virtue of subsonic aircraft NO x emission over China, and ozone changes less than 0.4 ppbv. When subsonic aircraft NO x emission over China is doubled, its influence is still relatively small.

  17. Emission of atmospheric pollutants out of Africa - Analysis of CARIBIC aircraft air samples

    NASA Astrophysics Data System (ADS)

    Thorenz, Ute R.; Baker, Angela K.; Schuck, Tanja; van Velthoven, Peter F. J.; Ziereis, Helmut; Brenninkmeijer, Carl A. M.

    2014-05-01

    Africa is the single largest continental source of biomass burning (BB) emissions. The burning African savannas and tropical forests are a source for a wide range of chemical species, which are important for global atmospheric chemistry, especially for the pristine Southern Hemisphere. Emitted compounds include carbon monoxide (CO), nitrogen oxides (NOx), hydrocarbons, oxygenated hydrocarbons and particles. Deep convection over Central Africa transports boundary layer emissions to the free troposphere making aircraft-based observations useful for investigation of surface emissions and examination of transport and chemistry processes over Africa The CARIBIC project (Civil Aircraft for the Regular Investigation of the Atmosphere Based on an Instrument Container, www.caribic-atmosphere.com part of IAGOS www.iagos.org) is a long term atmospheric measurement program using an instrument container deployed aboard a Lufthansa Airbus A340-600 for a monthly sequence of long-distance passenger flights. Besides the online measurements mixing ratios of greenhouse gases and a suite of C2-C8 non methane hydrocarbons (NMHCs) are measured from flask samples collected at cruise altitude. During northern hemispheric winter 2010/2011 CARIBIC flights took place from Frankfurt to Cape Town and Johannesburg in South Africa. Several BB tracers like methane, CO and various NMHCs were found to be elevated over tropical Africa. Using tracer-CO- and tracer-NOy-correlations emissions were characterized. The NMHC-CO correlations show monthly changing slopes, indicating a change in burned biomass, major fire stage, source region and/or other factors influencing NMHC emissions. To expand our analysis of emission sources a source region data filter was used, based on backward trajectories calculated along the flight tracks. Taking all CARIBIC samples into account having backward trajectories to the African boundary layer the dataset was enlarged from 77 to 168 samples. For both datasets tracer

  18. Characterization of lubrication oil emissions from aircraft engines.

    PubMed

    Yu, Zhenhong; Liscinsky, David S; Winstead, Edward L; True, Bruce S; Timko, Michael T; Bhargava, Anuj; Herndon, Scott C; Miake-Lye, Richard C; Anderson, Bruce E

    2010-12-15

    In this first ever study, particulate matter (PM) emitted from the lubrication system overboard breather vent for two different models of aircraft engines has been systematically characterized. Lubrication oil was confirmed as the predominant component of the emitted particulate matter based upon the characteristic mass spectrum of the pure oil. Total particulate mass and size distributions of the emitted oil are also investigated by several high-sensitivity aerosol characterization instruments. The emission index (EI) of lubrication oil at engine idle is in the range of 2-12 mg kg(-1) and increases with engine power. The chemical composition of the oil droplets is essentially independent of engine thrust, suggesting that engine oil does not undergo thermally driven chemical transformations during the ∼4 h test window. Volumetric mean diameter is around 250-350 nm for all engine power conditions with a slight power dependence.

  19. Measuring soot particles from automotive exhaust emissions

    NASA Astrophysics Data System (ADS)

    Andres, Hanspeter; Lüönd, Felix; Schlatter, Jürg; Auderset, Kevin; Jordan-Gerkens, Anke; Nowak, Andreas; Ebert, Volker; Buhr, Egbert; Klein, Tobias; Tuch, Thomas; Wiedensohler, Alfred; Mamakos, Athanasios; Riccobono, Francesco; Discher, Kai; Högström, Richard; Yli-Ojanperä, Jaakko; Quincey, Paul

    2014-08-01

    The European Metrology Research Programme participating countries and the European Union jointly fund a three year project to address the need of the automotive industry for a metrological sound base for exhaust measurements. The collaborative work on particle emissions involves five European National Metrology Institutes, the Tampere University of Technology, the Joint Research Centre for Energy and Transport and the Leibniz Institute for Tropospheric Research. On one hand, a particle number and size standard for soot particles is aimed for. Eventually this will allow the partners to provide accurate and comparable calibrations of measurement instruments for the type approval of Euro 5b and Euro 6 vehicles. Calibration aerosols of combustion particles, silver and graphite proof partially suitable. Yet, a consensus choice together with instrument manufactures is pending as the aerosol choice considerably affects the number concentration measurement. Furthermore, the consortium issued consistent requirements for novel measuring instruments foreseen to replace today's opacimeters in regulatory periodic emission controls of soot and compared them with European legislative requirements. Four partners are conducting a metrological validation of prototype measurement instruments. The novel instruments base on light scattering, electrical, ionisation chamber and diffusion charging sensors and will be tested at low and high particle concentrations. Results shall allow manufacturers to further improve their instruments to comply with legal requirements.

  20. A study of extractive and remote-sensing sampling and measurement of emissions from military aircraft engines

    NASA Astrophysics Data System (ADS)

    Cheng, Meng-Dawn; Corporan, Edwin

    2010-12-01

    Aircraft emissions contribute to the increased atmospheric burden of particulate matter (PM) that plays an important role in air quality, human health, visibility, contrail formation and climate change. Sampling and measurement of modern aircraft emissions at the engine exhaust plane (EEP) for engine and fuel certification remains challenging, as no agency-certified method is available. In this paper we summarize the results of three recent field studies devoted to investigate the consistency and applicability of "extractive" and "optical remote-sensing" (ORS) technologies in the sampling and measurement of gaseous and PM emitted by a number of military aircraft engines. Three classes of military engines were investigated; these include T56, TF33, and T700 & T701C types of engines, which consume 70-80% of the military aviation fuel each year. JP-8 and Fischer-Tropsch (FT)-derived paraffinic fuels were used to study the effect of fuels. It was found that non-volatile particles in the engine emissions were in the 20 nm range for the low power condition of new helicopter engines to 80 nm for the high power condition of legacy engines. Elemental analysis indicated little metals were present on particles, while most of the materials on the exhaust particles were carbon and sulfate based. Alkanes, carbon monoxide, carbon dioxide, nitrogen oxides, sulfur dioxide, formaldehyde, ethylene, acetylene and propylene were detected. The last five species were most noticeable only under low engine power. The emission indices calculated based on the ORS data deviate significantly from those based on the extractive data. Nevertheless, the ORS techniques were useful in the sense that it provided non-intrusive real-time detection of species in the exhaust plume, which warrants further development. The results obtained in this program help validate sampling methodology and measurement techniques used for non-volatile PM aircraft emissions as described in the SAE AIR6037 (2009).

  1. An Evaluation of Aircraft Emissions Inventory Methodology by Comparisons with Reported Airline Data

    NASA Technical Reports Server (NTRS)

    Daggett, D. L.; Sutkus, D. J.; DuBois, D. P.; Baughcum, S. L.

    1999-01-01

    This report provides results of work done to evaluate the calculation methodology used in generating aircraft emissions inventories. Results from the inventory calculation methodology are compared to actual fuel consumption data. Results are also presented that show the sensitivity of calculated emissions to aircraft payload factors. Comparisons of departures made, ground track miles flown and total fuel consumed by selected air carriers were made between U.S. Dept. of Transportation (DOT) Form 41 data reported for 1992 and results of simplified aircraft emissions inventory calculations. These comparisons provide an indication of the magnitude of error that may be present in aircraft emissions inventories. To determine some of the factors responsible for the errors quantified in the DOT Form 41 analysis, a comparative study of in-flight fuel flow data for a specific operator's 747-400 fleet was conducted. Fuel consumption differences between the studied aircraft and the inventory calculation results may be attributable to several factors. Among these are longer flight times, greater actual aircraft weight and performance deterioration effects for the in-service aircraft. Results of a parametric study on the variation in fuel use and NOx emissions as a function of aircraft payload for different aircraft types are also presented.

  2. Scheduled civil aircraft emission inventories for 1992: Database development and analysis

    NASA Technical Reports Server (NTRS)

    Baughcum, Steven L.; Tritz, Terrance G.; Henderson, Stephen C.; Pickett, David C.

    1996-01-01

    This report describes the development of a three-dimensional database of aircraft fuel burn and emissions (fuel burned, NOx, CO, and hydrocarbons) from scheduled commercial aircraft for each month of 1992. The seasonal variation in aircraft emissions was calculated for selected regions (global, North America, Europe, North Atlantic, and North Pacific). A series of parametric calculations were done to quantify the possible errors introduced from making approximations necessary to calculate the global emission inventory. The effects of wind, temperature, load factor, payload, and fuel tankering on fuel burn were evaluated to identify how they might affect the accuracy of aircraft emission inventories. These emissions inventories are available for use by atmospheric scientists conducting the Atmospheric Effects of Aviation Project (AEAP) modeling studies. Fuel burned and emissions of nitrogen oxides (NOx as N02), carbon monoxide, and hydrocarbons have been calculated on a 1 degree latitude x 1 degree longitude x 1 kilometer altitude grid and delivered to NASA as electronic files.

  3. Jet aircraft engine exhaust emissions database development: Year 1990 and 2015 scenarios

    NASA Technical Reports Server (NTRS)

    Landau, Z. Harry; Metwally, Munir; Vanalstyne, Richard; Ward, Clay A.

    1994-01-01

    Studies relating to environmental emissions associated with the High Speed Civil Transport (HSCT) military jet and charter jet aircraft were conducted by McDonnell Douglas Aerospace Transport Aircraft. The report includes engine emission results for baseline 1990 charter and military scenario and the projected jet engine emissions results for a 2015 scenario for a Mach 1.6 HSCT charter and military fleet. Discussions of the methodology used in formulating these databases are provided.

  4. Reductions in aircraft particulate emissions due to the use of Fischer-Tropsch fuels

    NASA Astrophysics Data System (ADS)

    Beyersdorf, A. J.; Timko, M. T.; Ziemba, L. D.; Bulzan, D.; Corporan, E.; Herndon, S. C.; Howard, R.; Miake-Lye, R.; Thornhill, K. L.; Winstead, E.; Wey, C.; Yu, Z.; Anderson, B. E.

    2014-01-01

    The use of alternative fuels for aviation is likely to increase due to concerns over fuel security, price stability, and the sustainability of fuel sources. Concurrent reductions in particulate emissions from these alternative fuels are expected because of changes in fuel composition including reduced sulfur and aromatic content. The NASA Alternative Aviation Fuel Experiment (AAFEX) was conducted in January-February 2009 to investigate the effects of synthetic fuels on gas-phase and particulate emissions. Standard petroleum JP-8 fuel, pure synthetic fuels produced from natural gas and coal feedstocks using the Fischer-Tropsch (FT) process, and 50% blends of both fuels were tested in the CFM-56 engines on a DC-8 aircraft. To examine plume chemistry and particle evolution with time, samples were drawn from inlet probes positioned 1, 30, and 145 m downstream of the aircraft engines. No significant alteration to engine performance was measured when burning the alternative fuels. However, leaks in the aircraft fuel system were detected when operated with the pure FT fuels as a result of the absence of aromatic compounds in the fuel. Dramatic reductions in soot emissions were measured for both the pure FT fuels (reductions in mass of 86% averaged over all powers) and blended fuels (66%) relative to the JP-8 baseline with the largest reductions at idle conditions. At 7% power, this corresponds to a reduction from 7.6 mg kg-1 for JP-8 to 1.2 mg kg-1 for the natural gas FT fuel. At full power, soot emissions were reduced from 103 to 24 mg kg-1 (JP-8 and natural gas FT, respectively). The alternative fuels also produced smaller soot (e.g., at 85% power, volume mean diameters were reduced from 78 nm for JP-8 to 51 nm for the natural gas FT fuel), which may reduce their ability to act as cloud condensation nuclei (CCN). The reductions in particulate emissions are expected for all alternative fuels with similar reductions in fuel sulfur and aromatic content regardless of the

  5. Experimental characterization of the COndensation PArticle counting System for high altitude aircraft-borne application

    NASA Astrophysics Data System (ADS)

    Weigel, R.; Hermann, M.; Curtius, J.; Voigt, C.; Walter, S.; Böttger, T.; Lepukhov, B.; Belyaev, G.; Borrmann, S.

    2009-06-01

    A characterization of the ultra-fine aerosol particle counter COPAS (COndensation PArticle counting System) for operation on board the Russian high altitude research aircraft M-55 Geophysika is presented. The COPAS instrument consists of an aerosol inlet and two dual-channel continuous flow Condensation Particle Counters (CPCs) operated with the chlorofluorocarbon FC-43. It operates at pressures between 400 and 50 hPa for aerosol detection in the particle diameter (dp) range from 6 nm up to 1 μm. The aerosol inlet, designed for the M-55, is characterized with respect to aspiration, transmission, and transport losses. The experimental characterization of counting efficiencies of three CPCs yields dp50 (50% detection particle diameter) of 6 nm, 11 nm, and 15 nm at temperature differences (ΔT) between saturator and condenser of 17°C, 30°C, and 33°C, respectively. Non-volatile particles are quantified with a fourth CPC, with dp50=11 nm. It includes an aerosol heating line (250°C) to evaporate H2SO4-H2O particles of 11 nmparticle emission index for the M-55 in the range of 1.4-8.4×1016 kg-1 fuel burned has been estimated based on measurements of the Geophysika's own exhaust.

  6. Sensitivity of urban air pollution to aircraft emissions in Paris area

    NASA Astrophysics Data System (ADS)

    Pison, I.; Menut, L.

    2003-04-01

    An accurate estimation of the emissions of primary pollutants is a key parameter for modeling surface concentrations observed during regional pollution events. These emissions are generally taken into account near the surface only, representing surface fluxes such as traffic, industries or biogenic sources. Other sources exist such as commercial aircraft emissions. In large urbanized areas, airports represent a non negligible source including landing and take-off of aircraft within the boundary layer. Even if these emissions certainly are not the most important process explaining urban pollution, the quantification of their impact on local pollution is rarely studied. This is the case of Paris where one national airport (Le Bourget) and two international airports (Roissy-Charles-de-Gaulle and Orly) are located less than 30~km from the center of the city. In this paper, we present the first model analysis of the impact of aircraft emissions over Paris area. Using a three-dimensional aircraft emission inventory we partly elaborated, we compare ozone surface concentrations obtained with and without these emissions by the chemistry-transport model CHIMERE. The observed differences show the spatial and temporal influence of these emissions within the boundary layer. This enables us to estimate the perturbations due to aircraft emissions on surface concentrations recorded in and around the city during the second intensive observation period (IOP2) of the ESQUIF project. Finally, aircraft emitted masses of VOCs and nitrogen oxides were disturbed in order to study the sensitivity of ozone concentrations to the accuracy of the inventory.

  7. Identification of lubrication oil in the particulate matter emissions from engine exhaust of in-service commercial aircraft.

    PubMed

    Yu, Zhenhong; Herndon, Scott C; Ziemba, Luke D; Timko, Michael T; Liscinsky, David S; Anderson, Bruce E; Miake-Lye, Richard C

    2012-09-04

    Lubrication oil was identified in the organic particulate matter (PM) emissions of engine exhaust plumes from in-service commercial aircraft at Chicago Midway Airport (MDW) and O'Hare International Airport (ORD). This is the first field study focused on aircraft lubrication oil emissions, and all of the observed plumes described in this work were due to near-idle engine operations. The identification was carried out with an Aerodyne high-resolution time-of-flight aerosol mass spectrometer (HR-ToF AMS) via a collaborative laboratory and field investigation. A characteristic mass marker of lubrication oil, I(85)/I(71), the ratio of ion fragment intensity between m/z = 85 and 71, was used to distinguish lubrication oil from jet engine combustion products. This AMS marker was based on ion fragmentation patterns measured using electron impact ionization for two brands of widely used lubrication oil in a laboratory study. The AMS measurements of exhaust plumes from commercial aircraft in this airport field study reveal that lubrication oil is commonly present in organic PM emissions that are associated with emitted soot particles, unlike the purely oil droplets observed at the lubrication system vent. The characteristic oil marker, I(85)/I(71), was applied to quantitatively determine the contribution from lubrication oil in measured aircraft plumes, which ranges from 5% to 100%.

  8. A STUDY OF EXTRACTIVE AND REMOTE-SENSING SAMPLING AND MEASUREMENT OF EMISSIONS FROM MILITARY AIRCRAFT ENGINES

    SciTech Connect

    Cheng, Mengdawn; Corporan, E.

    2010-01-01

    Aircraft emissions contribute to the increased atmospheric burden of particulate matter (e.g., black carbon and secondary organic compounds) that plays a role in air quality, contrail formation and climate change. Sampling and measurement of modern aircraft emissions at the engine exhaust plane (EEP) for to engine and fuel certification remains a daunting task, no agency-certified method is available for the task. In this paper we summarize the results of a recent study that was devoted to investigate both extractive and optical remote-sensing (ORS) technologies in sampling and measurement of gaseous and particulate matter (PM) emitted by a number of military aircraft engines operated with JP-8 and a Fischer-Tropsch (FT) fuel at various engine conditions. These engines include cargo, bomber, and helicopter types of military aircraft that consumes 70-80% of the military aviation fuel each year. The emission indices of selected pollutants are discussed as these data may be of interest for atmospheric modeling and for design of air quality control strategies around the airports and military bases. It was found that non-volatile particles in the engine emissions were all in the ultrafine range. The mean diameter of particles increased as the engine power increased; the mode diameters were in the 20nm range for the low power condition of a new helicopter engine to 80nm for the high power condition of a newly maintained bomber engine. Elemental analysis indicated little metals were present on particles in the exhaust, while most of the materials on the exhaust particles were based on carbon and sulfate. Carbon monoxide, carbon dioxide, nitrogen oxide, sulfur dioxide, formaldehyde, ethylene, acetylene, propylene, and alkanes were detected using both technologies. The last five species (in the air toxics category) were most noticeable only under the low engine power. The emission indices calculated based on the ORS data were however observed to differ significantly (up to

  9. Characterization of a Quadrotor Unmanned Aircraft System for Aerosol-Particle-Concentration Measurements.

    PubMed

    Brady, James M; Stokes, M Dale; Bonnardel, Jim; Bertram, Timothy H

    2016-02-02

    High-spatial-resolution, near-surface vertical profiling of atmospheric chemical composition is currently limited by the availability of experimental platforms that can sample in constrained environments. As a result, measurements of near-surface gradients in trace gas and aerosol particle concentrations have been limited to studies conducted from fixed location towers or tethered balloons. Here, we explore the utility of a quadrotor unmanned aircraft system (UAS) as a sampling platform to measure vertical and horizontal concentration gradients of trace gases and aerosol particles at high spatial resolution (1 m) within the mixed layer (0-100 m). A 3D Robotics Iris+ autonomous quadrotor UAS was outfitted with a sensor package consisting of a two-channel aerosol optical particle counter and a CO2 sensor. The UAS demonstrated high precision in both vertical (±0.5 m) and horizontal positions (±1 m), highlighting the potential utility of quadrotor UAS drones for aerosol- and trace-gas measurements within complex terrain, such as the urban environment, forest canopies, and above difficult-to-access areas such as breaking surf. Vertical profiles of aerosol particle number concentrations, acquired from flights conducted along the California coastline, were used to constrain sea-spray aerosol-emission rates from coastal wave breaking.

  10. Time dependent particle emission from fission products

    SciTech Connect

    Holloway, Shannon T; Kawano, Toshihiko; Moller, Peter

    2010-01-01

    Decay heating following nuclear fission is an important factor in the design of nuclear facilities; impacting a variety of aspects ranging from cooling requirements to shielding design. Calculations of decay heat, often assumed to be a simple product of activity and average decay product energy, are complicated by the so called 'pandemonium effect'. Elucidated in the 1970's this complication arises from beta-decays feeding high-energy nuclear levels; redistributing the available energy between betas and gammas. Increased interest in improving the theoretical predictions of decay probabilities has been, in part, motivated by the recent experimental effort utilizing the Total Absorption Gamma-ray Spectrometer (TAGS) to determine individual beta-decay transition probabilities to individual nuclear levels. Accurate predictions of decay heating require a detailed understanding of these transition probabilities, accurate representation of particle decays as well as reliable predictions of temporal inventories from fissioning systems. We will discuss a recent LANL effort to provide a time dependent study of particle emission from fission products through a combination of Quasiparticle Random Phase Approximation (QRPA) predictions of beta-decay probabilities, statistical Hauser-Feshbach techniques to obtain particle and gamma-ray emissions in statistical Hauser-Feshbach and the nuclear inventory code, CINDER.

  11. Jet engine exhaust emissions of high altitude commercial aircraft projected to 1990

    NASA Technical Reports Server (NTRS)

    Grobman, J.; Ingebo, R. D.

    1974-01-01

    Projected minimum levels of engine exhaust emissions that may be practicably achievable for future commercial aircraft operating at high-altitude cruise conditions are presented. The forecasts are based on:(1) current knowledge of emission characteristics of combustors and augmentors; (2) the status of combustion research in emission reduction technology; and (3) predictable trends in combustion systems and operating conditions as required for projected engine designs that are candidates for advanced subsonic or supersonic commercial aircraft fueled by either JP fuel, liquefied natural gas, or hydrogen. Results are presented for cruise conditions in terms of both an emission index (g constituent/kg fuel) and an emission rate (g constituent/hr).

  12. Stimulated Emission of Energetic Particles (SEEP).

    DTIC Science & Technology

    1987-11-30

    a.... W W w w w w w I I li IJr Ir % i "f J2 I l AD-A 188 724 MLMSCD068456 For Period Ending 30 September 1987 CD Contract N00014-79-C4824 0 IC FILE...CLASSIFICATION 0 -UNCLASSIFIED/UNLIMITED [ SAME AS RPT C:" DTIC USERS UNCLASSIFIED 22a NAME OF RESPONSIBLE INDIVIDUAL 22b TELEPHONE (Include Area Code) 22c O...34---" ,. LMSC/D068456 . 0 SEEP FINAL REPORT I. OBJECTIVES OF THE SEEP PROGRAM The SEEP (Stimulated Emission of Energetic Particles) program had important

  13. Sensitivity of stratospheric ozone to present and possible future aircraft emissions

    SciTech Connect

    Wuebbles, D.J.; Kinnison, D.E.

    1990-08-01

    The aircraft industry is showing renewed interest in the development of supersonic, high flying aircraft for intercontinental passenger flights. There appears to be confidence that such high-speed civil transports can be designed, and that aircraft will be economically viable as long as they are also environmentally acceptable. As such, it is important to establish the potential for such environmental problems early in the aircraft design. Initial studies with LLNL models of global atmospheric chemical, radiative, and transport processes have indicated that substantial decreases in stratospheric ozone concentrations could result from emissions of NO{sub x} from aircraft flying the stratosphere, depending on the fleet size and magnitude of the engine emissions. The purpose of this study is to build on previous analyses of potential aircraft emission effects on ozone in order to better define the sensitivity of ozone to such emissions. In addition to NO{sub x}, the effects of potential emissions of carbon monoxide and water vapor are also examined. More realistic scenarios for the emissions as a function of altitude, latitude, and season are examined in comparison to prior analyses. These studies indicate that the effects on ozone are sensitive to the altitude and latitude, as well as the magnitude, of the emissions.

  14. Comparison of methodologies estimating emissions of aircraft pollutants, environmental impact assessment around airports

    SciTech Connect

    Kurniawan, Jermanto S. Khardi, S.

    2011-04-15

    Air transportation growth has increased continuously over the years. The rise in air transport activity has been accompanied by an increase in the amount of energy used to provide air transportation services. It is also assumed to increase environmental impacts, in particular pollutant emissions. Traditionally, the environmental impacts of atmospheric emissions from aircraft have been addressed in two separate ways; aircraft pollutant emissions occurring during the landing and take-off (LTO) phase (local pollutant emissions) which is the focus of this study, and the non-LTO phase (global/regional pollutant emissions). Aircraft pollutant emissions are an important source of pollution and directly or indirectly harmfully affect human health, ecosystems and cultural heritage. There are many methods to asses pollutant emissions used by various countries. However, using different and separate methodology will cause a variation in results, some lack of information and the use of certain methods will require justification and reliability that must be demonstrated and proven. In relation to this issue, this paper presents identification, comparison and reviews of some of the methodologies of aircraft pollutant assessment from the past, present and future expectations of some studies and projects focusing on emissions factors, fuel consumption, and uncertainty. This paper also provides reliable information on the impacts of aircraft pollutant emissions in short term and long term predictions.

  15. EPA Takes First Steps to Address Greenhouse Gas Emissions from Aircraft

    EPA Pesticide Factsheets

    WASHINGTON - The U.S. Environmental Protection Agency (EPA) is proposing to find under the Clean Air Act that greenhouse gas (GHG) emissions from commercial aircraft contribute to the pollution that causes climate change endangering the health and welfare

  16. Status review of NASA programs for reducing aircraft gas turbine engine emissions

    NASA Technical Reports Server (NTRS)

    Rudey, R. A.

    1976-01-01

    Programs initiated by NASA to develop and demonstrate low emission advanced technology combustors for reducing aircraft gas turbine engine pollution are reviewed. Program goals are consistent with urban emission level requirements as specified by the U. S. Environmental Protection Agency and with upper atmosphere cruise emission levels as recommended by the U. S. Climatic Impact Assessment Program and National Research Council. Preliminary tests of advanced technology combustors indicate that significant reductions in all major pollutant emissions should be attainable in present generation aircraft gas turbine engines without adverse effects on fuel consumption. Preliminary test results from fundamental studies indicate that extremely low emission combustion systems may be possible for future generation jet aircraft. The emission reduction techniques currently being evaluated in these programs are described along with the results and a qualitative assessment of development difficulty.

  17. Results and status of the NASA aircraft engine emission reduction technology programs

    NASA Technical Reports Server (NTRS)

    Jones, R. E.; Diehl, L. A.; Petrash, D. A.; Grobman, J.

    1978-01-01

    The results of an aircraft engine emission reduction study are reviewed in detail. The capability of combustor concepts to produce significantly lower levels of exhaust emissions than present production combustors was evaluated. The development status of each combustor concept is discussed relative to its potential for implementation in aircraft engines. Also, the ability of these combustor concepts to achieve proposed NME and NCE EPA standards is discussed.

  18. Aircraft Emission Scenarios Projected in Year 2015 for the NASA Technology Concept Aircraft (TCA) High Speed Civil Transport

    NASA Technical Reports Server (NTRS)

    Baughcum, Steven L.; Henderson, Stephen C.

    1998-01-01

    This report describes the development of a three-dimensional database of aircraft fuel burn and emissions (fuel burned, NOx, CO, and hydrocarbons) from projected fleets of high speed civil transports (HSCTs) on a universal airline network. Inventories for 500 and 1000 HSCT fleets, as well as the concurrent subsonic fleets, were calculated. The HSCT scenarios are calculated using the NASA technology concept airplane (TCA) and update an earlier report. These emissions inventories are available for use by atmospheric scientists conducting the Atmospheric Effects of Stratospheric Aircraft (AESA) modeling studies. Fuel burned and emissions of nitrogen oxides (NOx as NO2), carbon monoxide, and hydrocarbons have been calculated on a 1 degree latitude x 1 degree longitude x 1 kilometer pressure altitude grid and delivered to NASA as electronic files.

  19. Summary of the general aviation manufacturers' position on aircraft piston engine emissions

    NASA Technical Reports Server (NTRS)

    Helms, J. L.

    1976-01-01

    The General Aviation Manufacturers recommended that the EPA rescind the aircraft piston engine emissions regulations currently on the books. The reason was the very small emission reduction potential and the very poor benefit-cost ratio involved in this form of emission reduction. The limited resources of this industry can far better be devoted to items of much greater benefit to the citizens of this country - reducing noise, improving fuel efficiency (which will incidently reduce exhaust emissions), and improving the safety, operational, and economic aspects of aircraft, all far greater contributions to our total national transportation system.

  20. Quantification of the impact of aircraft traffic emissions on tropospheric ozone over Paris area

    NASA Astrophysics Data System (ADS)

    Pison, Isabelle; Menut, Laurent

    Accurate estimations of the emissions of primary pollutants are crucial for the modeling of photo-oxidants' concentrations. For a majority of chemistry-transport models (CTMs), these emissions are taken into account near the surface only. They are expressed as surface fluxes and represent surface activities such as traffic, industries or biogenic processes. However, in the vicinity of large cities, commercial aircraft emissions represent a nonnegligible source, located both at the surface and at altitude, including landing and take-off of aircraft within the boundary layer. This is the case of Paris where one national airport (Le Bourget) and two international airports (Roissy-Charles-de-Gaulle and Orly) are located less than 30 km away from the city center. This study presents the first-model analysis of the impact of aircraft emissions on photo-oxidant concentrations over the Paris area. Using a three-dimensional aircraft emission inventory, we compare ozone surface concentrations obtained with and without these emissions by running the CTM CHIMERE during the second Intensive Observation Period of the ESQUIF project. The simulated differences enable us to estimate the impact of aircraft traffic emissions on ozone surface concentrations in and around the city. The results showed that the maximum impact, which consists in a fast ozone titration by NO near the airports within the surface layer, occurs during the night. In remote areas and at altitude, adding new emissions enhanced photo-chemistry during the afternoon. In order to estimate the impact of the uncertainty of our inventory, aircraft emitted masses of volatile organic compounds (VOCs) and NO x are perturbed. The results showed that NO x air traffic emissions have a more important impact than VOC emissions, particularly during the night and near the sources. Nevertheless, these variations of air traffic emissions do not change previous conclusions.

  1. Experiment to Characterize Aircraft Volatile Aerosol and Trace-Species Emissions (EXCAVATE)

    NASA Technical Reports Server (NTRS)

    Anderson, B. E.; Branham, H.-S.; Hudgins, C. H.; Plant, J. V.; Ballenthin, J. O.; Miller, T. M.; Viggiano, A. A.; Blake, D. R.; Boudries, H.; Canagaratna, M.

    2005-01-01

    The Experiment to Characterize Aircraft Volatile and Trace Species Emissions (EXCAVATE) was conducted at Langley Research Center (LaRC) in January 2002 and focused upon assaying the production of aerosols and aerosol precursors by a modern commercial aircraft, the Langley B757, during ground-based operation. Remaining uncertainty in the postcombustion fate of jet fuel sulfur contaminants, the need for data to test new theories of particle formation and growth within engine exhaust plumes, and the need for observations to develop air quality models for predicting pollution levels in airport terminal areas were the primary factors motivating the experiment. NASA's Atmospheric Effects of Aviation Project (AEAP) and the Ultra Effect Engine Technology (UEET) Program sponsored the experiment which had the specific objectives of determining ion densities; the fraction of fuel S converted from S(IV) to S(VI); the concentration and speciation of volatile aerosols and black carbon; and gas-phase concentrations of long-chain hydrocarbon and PAH species, all as functions of engine power, fuel composition, and plume age.

  2. RFID Transponders' Radio Frequency Emissions in Aircraft Communication and Navigation Radio Bands

    NASA Technical Reports Server (NTRS)

    Nguyen, Truong X.; Ely, Jay J.; Williams, Reuben A.; Koppen, Sandra V.; Salud, Maria Theresa P.

    2006-01-01

    Radiated emissions in aircraft communication and navigation bands are measured from several active radio frequency identification (RFID) tags. The individual tags are different in design and operations. They may also operate in different frequency bands. The process for measuring the emissions is discussed, and includes tag interrogation, reverberation chamber testing, and instrument settings selection. The measurement results are described and compared against aircraft emission limits. In addition, interference path loss for the cargo bays of passenger aircraft is measured. Cargo bay path loss is more appropriate for RFID tags than passenger cabin path loss. The path loss data are reported for several aircraft radio systems on a Boeing 747 and an Airbus A320.

  3. Scheduled Civil Aircraft Emission Inventories for 1999: Database Development and Analysis

    NASA Technical Reports Server (NTRS)

    Sutkus, Donald J., Jr.; Baughcum, Steven L.; DuBois, Douglas P.

    2001-01-01

    This report describes the development of a three-dimensional database of aircraft fuel burn and emissions (NO(x), CO, and hydrocarbons) for the scheduled commercial aircraft fleet for each month of 1999. Global totals of emissions and fuel burn for 1999 are compared to global totals from 1992 and 2015 databases. 1999 fuel burn, departure and distance totals for selected airlines are compared to data reported on DOT Form 41 to evaluate the accuracy of the calculations. DOT Form T-100 data were used to determine typical payloads for freighter aircraft and this information was used to model freighter aircraft more accurately by using more realistic payloads. Differences in the calculation methodology used to create the 1999 fuel burn and emissions database from the methodology used in previous work are described and evaluated.

  4. Dust emissions created by low-level rotary-winged aircraft flight over desert surfaces

    NASA Astrophysics Data System (ADS)

    Gillies, J. A.; Etyemezian, V.; Kuhns, H.; McAlpine, J. D.; King, J.; Uppapalli, S.; Nikolich, G.; Engelbrecht, J.

    2010-03-01

    There is a dearth of information on dust emissions from sources that are unique to U.S. Department of Defense testing and training activities. Dust emissions of PM 10 and PM 2.5 from low-level rotary-winged aircraft travelling (rotor-blade ≈7 m above ground level) over two types of desert surfaces (i.e., relatively undisturbed desert pavement and disturbed desert soil surface) were characterized at the Yuma Proving Ground (Yuma, AZ) in May 2007. Fugitive emissions are created by the shear stress of the outflow of high speed air created by the rotor-blade. The strength of the emissions was observed to scale primarily as a function of forward travel speed of the aircraft. Speed affects dust emissions in two ways: 1) as speed increases, peak shear stress at the soil surface was observed to decline proportionally, and 2) as the helicopter's forward speed increases its residence time over any location on the surface diminishes, so the time the downward rotor-generated flow is acting upon that surface must also decrease. The state of the surface over which the travel occurs also affects the scale of the emissions. The disturbed desert test surface produced approximately an order of magnitude greater emission than the undisturbed surface. Based on the measured emission rates for the test aircraft and the established scaling relationships, a rotary-winged aircraft similar to the test aircraft traveling 30 km h -1 over the disturbed surface would need to travel 4 km to produce emissions equivalent to one kilometer of travel by a light wheeled military vehicle also traveling at 30 km h -1 on an unpaved road. As rotary-winged aircraft activity is substantially less than that of off-road vehicle military testing and training activities it is likely that this source is small compared to emissions created by ground-based vehicle movements.

  5. Secondary particle emission from sapphire single crystal

    NASA Astrophysics Data System (ADS)

    Minnebaev, K. F.; Khvostov, V. V.; Zykova, E. Yu.; Tolpin, K. A.; Colligon, J. S.; Yurasova, V. E.

    2015-07-01

    Secondary ion emission from sapphire single crystal has been studied experimentally and by means of computer simulation. The particular oscillations of secondary ion energy spectra and two specific maxima of O+ and Al+ ions were observed under irradiation of (0001) sapphire face by 1 and 10 keV Ar+ ions. We have explained this by the interplay of the charge exchange processes between moving particles and solids. The existence of two maxima in energy spectra of O+ and Al+ secondary ions can be also connected with special features of single-crystal sputtering: the low-energy peak can be formed by random sputtering and the high-energy peak from focusing collisions. In addition some similarity was found between the positions of low-energy maximum in energy spectra of Al+ ions emitted from sapphire and the principal maxima of Al+ ions ejected from the aluminum single crystal. This indicates a possibility to explain the presence of low-energy maximum in energy spectra of secondary ions ejecting from sapphire by emission of Al+ ions from aluminum islands appearing in a number of cases on the sapphire surface due to preferential sputtering of oxygen. These different mechanisms of creating the energy spectra of ions emitted from sapphire should be taken in account.

  6. Global contrail coverage simulated by CAM5 with the inventory of 2006 global aircraft emissions

    NASA Astrophysics Data System (ADS)

    Chen, Chih-Chieh; Gettelman, Andrew; Craig, Cheryl; Minnis, Patrick; Duda, David P.

    2012-02-01

    This paper documents the incorporation of an inventory of the AEDT (Aviation Environmental Design Tool) global commercial aircraft emissions for the year of 2006 into the National Center for Atmospheric Research Community Earth System Model (CESM) version 1. The original dataset reports aircraft emission mass of ten species on an hourly basis which is converted to monthly emission mixing ratio tendencies as the released version of the dataset. We also describe how the released aircraft emission dataset is incorporated into CESM. A contrail parameterization is implemented in the CESM in which it is assumed that persistent contrails initially form when aircraft water vapor emissions experience a favorable atmospheric environment. Both aircraft emissions and ambient humidity are attributed to the formation of contrails. The ice water content of contrails is assumed to follow an empirical function of atmospheric temperature which determines the cloud fraction associated with contrails. Our modeling study indicates that the simulated global contrail coverage is sensitive to the vertical resolution of the GCMs in the upper troposphere and lower stratosphere because of model assumptions about the vertical overlap structure of clouds. Furthermore, the extent of global contrail coverage simulated by CESM exhibits a seasonal cycle which is in broad agreement with observations.

  7. Analysis of the effects of meteorology on aircraft exhaust dispersion and deposition using a Lagrangian particle model.

    PubMed

    Pecorari, Eliana; Mantovani, Alice; Franceschini, Chiara; Bassano, Davide; Palmeri, Luca; Rampazzo, Giancarlo

    2016-01-15

    The risk of air quality degradation is of considerable concern particularly for those airports that are located near urban areas. The ability to quantitatively predict the effects of air pollutants originated by airport operations is important for assessing air quality and the related impacts on human health. Current emission regulations have focused on local air quality in the proximity of airports. However, an integrated study should consider the effects of meteorological events, at both regional and local level, that can affect the dispersion and the deposition of exhausts. Rigorous scientific studies and extensive experimental data could contribute to the analysis of the impacts of airports expansion plans. This paper is focused on the analysis of the effects of meteorology on aircraft emission for the Marco Polo Airport in Venice. This is the most important international airport in the eastern part of the Po' Valley, one of the most polluted area in Europe. Air pollution is exacerbated by meteorology that is a combination of large and local scale effects that do not allow significant dispersion. Moreover, the airport is located near Venice, a city of noteworthy cultural and architectural relevance, and nearby the lagoon that hosts several areas of outstanding ecological importance at European level (Natura 2000 sites). Dispersion and deposit of the main aircraft exhausts (NOx, HC and CO) have been evaluated by using a Lagrangian particle model. Spatial and temporal aircraft exhaust dispersion has been analyzed for LTO cycle. Aircraft taxiing resulted to be the most impacting aircraft operation especially for the airport working area and its surroundings, however occasionally peaks may be observed even at high altitudes when cruise mode starts. Mixing height can affect concentrations more significantly than the concentrations in the exhausts themselves. An increase of HC and CO concentrations (15-50%) has been observed during specific meteorological events.

  8. Avco Lycoming/NASA contract status. [on reduction of emissions from aircraft piston engines

    NASA Technical Reports Server (NTRS)

    Duke, L. C.

    1976-01-01

    The standards promulgated by the Environmental Protection Agency (EPA) for carbon monoxide (CO), unburned hydrocarbon (HC), and oxides-of-nitrogen (NOx) emissions were the basis in a study of ways to reduce emissions from aircraft piston engines. A variable valve timing system, ultrasonic fuel atomization, and ignition system changes were postulated.

  9. 77 FR 76842 - Exhaust Emissions Standards for New Aircraft Gas Turbine Engines and Identification Plate for...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-12-31

    ... action revises the standards for oxides of nitrogen and test procedures for exhaust emissions based on... Environmental Protection Agency (EPA) proposed new aircraft engine emission standards for oxides of nitrogen (NO... Protection (CAEP) of ICAO uses to differentiate the CAEP work cycles that produce new standards. For...

  10. Jet aircraft engine emissions database development: 1992 military, charter, and nonscheduled traffic

    NASA Technical Reports Server (NTRS)

    Metwally, Munir

    1995-01-01

    Studies relating to environmental emissions database for the military, charter, and non-scheduled traffic for the year 1992 were conducted by McDonnell Douglas Aerospace Transport Aircraft. The report also includes a comparison with a previous emission database for year 1990. Discussions of the methodology used in formulating these databases are provided.

  11. Advanced combustion techniques for controlling NO sub x emissions of high altitude cruise aircraft

    NASA Technical Reports Server (NTRS)

    Rudey, R. A.; Reck, G. M.

    1976-01-01

    An array of experiments designed to explore the potential of advanced combustion techniques for controlling the emissions of aircraft into the upper atmosphere was discussed. Of particular concern are the oxides of nitrogen (NOx) emissions into the stratosphere. The experiments utilize a wide variety of approaches varying from advanced combustor concepts to fundamental flame tube experiments. Results are presented which indicate that substantial reductions in cruise NOx emissions should be achievable in future aircraft engines. A major NASA program is described which focuses the many fundamental experiments into a planned evolution and demonstration of the prevaporized-premixed combustion technique in a full-scale engine.

  12. Technology for controlling emissions of oxides of nitrogen from supersonic cruise aircraft

    NASA Technical Reports Server (NTRS)

    Reck, G. M.; Rudey, R. A.

    1976-01-01

    Various experiments are sponsored and conducted by NASA to explore the potential of advanced combustion techniques for controlling aircraft engine emissions into the upper atmosphere. Of particular concern are the oxide of nitrogen (NOx) emissions into the stratosphere. The experiments utilize a wide variety of approaches varying from advanced combustor concepts to fundamental flame tube experiments. Results are presented which indicate that substantial reductions in cruise NOx emissions should be achievable in future aircraft engines. A major NASA program is described which focuses the many fundamental experiments into a planned evolution and demonstration of the prevaporized-premixed combustion technique in a full-scale engine.

  13. Efficient Formation of Stratospheric Aerosol for Climate Engineering by Emission of Condensible Vapor from Aircraft

    NASA Technical Reports Server (NTRS)

    Pierce, Jeffrey R.; Weisenstein, Debra K.; Heckendorn, Patricia; Peter. Thomas; Keith, David W.

    2010-01-01

    Recent analysis suggests that the effectiveness of stratospheric aerosol climate engineering through emission of non-condensable vapors such as SO2 is limited because the slow conversion to H2SO4 tends to produce aerosol particles that are too large; SO2 injection may be so inefficient that it is difficult to counteract the radiative forcing due to a CO2 doubling. Here we describe an alternate method in which aerosol is formed rapidly in the plume following injection of H2SO4, a condensable vapor, from an aircraft. This method gives better control of particle size and can produce larger radiative forcing with lower sulfur loadings than SO2 injection. Relative to SO2 injection, it may reduce some of the adverse effects of geoengineering such as radiative heating of the lower stratosphere. This method does not, however, alter the fact that such a geoengineered radiative forcing can, at best, only partially compensate for the climate changes produced by CO2.

  14. Development of EPA aircraft piston engine emission standards. [for air quality

    NASA Technical Reports Server (NTRS)

    Houtman, W.

    1976-01-01

    Piston engine light aircraft are significant sources of carbon monoxide in the vicinity of high activity general aviation airports. Substantial reductions in carbon monoxide were achieved by fuel mixture leaning using improved fuel management systems. The air quality impact of the hydrocarbon and oxides of nitrogen emissions from piston engine light aircraft were insufficient to justify the design constraints being confronted in present control system developments.

  15. The impact of emissions standards on the design of aircraft gas turbine engine combustors

    NASA Technical Reports Server (NTRS)

    Rudey, R. A.

    1976-01-01

    Effective emission control techniques have been identified and a wide spectrum of potential applications for these techniques to existing and advanced engines are being considered. Results from advanced combustor concept evaluations and from fundamental experiments are presented and discussed and comparisons are made with existing EPA emission standards and recommended levels for high altitude cruise. The impact that the advanced low emission concepts may impose on future aircraft engine combustor designs and related engine components is discussed.

  16. Atmospheric and environmental impacts of volcanic ash particle emissions

    NASA Astrophysics Data System (ADS)

    Durant, Adam

    2010-05-01

    Globally, at any one time, there may be 20 volcanoes erupting that collectively emit a constant flux of gases and aerosol, including silicate particles (tephra), to the atmosphere which influences processes including cloud microphysics, heterogeneous chemistry and radiative balance. The nature and impact of atmospheric volcanic particle fluxes depend on total mass erupted, emission rate, emission source location, physical and chemical properties of the particles, and the location and residence time of the particles in the atmosphere. Removal of ash particles from the atmosphere through sedimentation is strongly influenced by particle aggregation through hydrometeor formation, and convective instabilities such as mammatus. I will address the following questions: What are the atmospheric impacts of volcanic ash emissions? What controls the residence time of volcanic particles in the atmosphere? What affects particle accumulation at the surface? And what are the human and environmental impacts of ash fallout?

  17. The atmospheric cosmic- and solar energetic particle radiation environment at aircraft altitudes.

    PubMed

    O'Brien, K; Friedberg, W; Smart, D F; Sauer, H H

    1998-01-01

    Galactic cosmic rays interact with the solar wind, the earth's magnetic field and hadron, lepton and photon fields at aircraft altitudes. In addition to cosmic rays, energetic particles generated by solar activity bombard the earth from time to time. These particles, while less energetic than cosmic rays, also produce radiation fields at aircraft altitudes which have qualitatively the same properties as atmospheric cosmic rays. We have used a code based on transport theory to calculate atmospheric cosmic-ray quantities and compared them with experimental data. Agreement with these data is seen to be good. We have then used this code to calculate equivalent doses to aircraft crews. We have also used the code to calculate radiation doses from several large solar energetic particle events which took place in 1989, including the very large event that occurred on September 29th and 30th of that year. The spectra incident on the atmosphere were determined assuming diffusive shock theory.

  18. Calibration and demonstration of a condensation nuclei counting system for airborne measurements of aircraft exhausted particles

    NASA Astrophysics Data System (ADS)

    Cofer, Wesley R.; Anderson, Bruce E.; Winstead, Edward L.; Bagwell, Donald R.

    A system of multiple continuous-flow condensation nuclei counters (CNC) was assembled, calibrated, and demonstrated on a NASA T-39 Sabreliner jet aircraft. The mission was to penetrate the exhaust plumes and/or contrails of other subsonic jet aircraft and determine the concentrations of submicrometer diameter aerosol particles. Mission criteria required rapid response measurements ( ˜ 1 s) at aircraft cruise altitudes (9-12 km). The CNC sampling system was optimized to operate at 160 Torr. Aerosol samples were acquired through an externally mounted probe. Installed downstream of the probe was a critical flow orifice that provided sample to the CNC system. The orifice not only controlled volumetric flow rate, but also dampened probe pressure/flow oscillations encountered in the turbulent aircraft-wake vortex environment. Laboratory calibrations with NaCl particles under representative conditions are reported that indicate small amounts of particle loss and a maximum measurement efficiency of ˜ 75% for particles with diameters ranging from ⩾ 0.01- ⩽ 0.18 μm Data from exhaust/contrail samplings of a NASA B757 and DC-8 at cruise altitude are discussed. Data include exhaust/contrail measurements made during periods in which the B757 port jet engine burned low-sulfur fuel while the starboard engine simultaneously burned specially prepared high-sulfur fuel. The data discussed highlight the CNC systems performance, and introduce new observations pertinent to the behavior of sulfur in aircraft exhaust aerosol chemistry.

  19. Determination and Applications of Environmental Costs at Different Sized Airports: Aircraft Noise and Engine Emissions

    NASA Technical Reports Server (NTRS)

    Lu, Cherie; Lierens, Abigail

    2003-01-01

    With the increasing trend of charging for externalities and the aim of encouraging the sustainable development of the air transport industry, there is a need to evaluate the social costs of these undesirable side effects, mainly aircraft noise and engine emissions, for different airports. The aircraft noise and engine emissions social costs are calculated in monetary terms for five different airports, ranging from hub airports to small regional airports. The number of residences within different levels of airport noise contours and the aircraft noise classifications are the main determinants for accessing aircraft noise social costs. Whist, based on the damages of different engine pollutants on the human health, vegetation, materials, aquatic ecosystem and climate, the aircraft engine emissions social costs vary from engine types to aircraft categories. The results indicate that the relationship appears to be curvilinear between environmental costs and the traffic volume of an airport. The results and methodology of environmental cost calculation could input for to the proposed European wide harmonized noise charges as well as the social cost benefit analysis of airports.

  20. Aircraft-Based Measurements of Point Source Methane Emissions in the Barnett Shale Basin.

    PubMed

    Lavoie, Tegan N; Shepson, Paul B; Cambaliza, Maria O L; Stirm, Brian H; Karion, Anna; Sweeney, Colm; Yacovitch, Tara I; Herndon, Scott C; Lan, Xin; Lyon, David

    2015-07-07

    We report measurements of methane (CH4) emission rates observed at eight different high-emitting point sources in the Barnett Shale, Texas, using aircraft-based methods performed as part of the Barnett Coordinated Campaign. We quantified CH4 emission rates from four gas processing plants, one compressor station, and three landfills during five flights conducted in October 2013. Results are compared to other aircraft- and surface-based measurements of the same facilities, and to estimates based on a national study of gathering and processing facilities emissions and 2013 annual average emissions reported to the U.S. EPA Greenhouse Gas Reporting Program (GHGRP). For the eight sources, CH4 emission measurements from the aircraft-based mass balance approach were a factor of 3.2-5.8 greater than the GHGRP-based estimates. Summed emissions totaled 7022 ± 2000 kg hr(-1), roughly 9% of the entire basin-wide CH4 emissions estimated from regional mass balance flights during the campaign. Emission measurements from five natural gas management facilities were 1.2-4.6 times larger than emissions based on the national study. Results from this study were used to represent "super-emitters" in a newly formulated Barnett Shale Inventory, demonstrating the importance of targeted sampling of "super-emitters" that may be missed by random sampling of a subset of the total.

  1. Studies of diesel engine particle emissions during transient operations using an Engine Exhaust Particle Sizer

    SciTech Connect

    Wang, Jian; Storey, John Morse; Domingo, Norberto; Huff, Shean P; Thomas, John F; West, Brian H; Lee, Doh-Won

    2006-01-01

    Diesel engine particle emissions during transient operations, including emissions during FTP transient cycles and during active regenerations of a NOx adsorber, were studied using a fast Engine Exhaust Particle Sizer (EEPS). For both fuels tested, a No. 2 certification diesel and a low sulfur diesel (BP-15), high particle concentrations and emission rates were mainly associated with heavy engine acceleration, high speed, and high torque during transient cycles. Averaged over the FTP transient cycle, the particle number concentration during tests with the certification fuel was 1.2e8/cm3, about four times the particle number concentration observed during tests using the BP-15 fuel. The effect of each engine parameter on particle emissions was studied. During tests using BP-15, the particle number emission rate was mainly controlled by the engine speed and torque, whereas for Certification fuel, the engine acceleration also had a strong effect on number emission rates. The effects of active regenerations of a diesel NOx adsorber on particle emissions were also characterized for two catalyst regeneration strategies: Delayed Extended Main (DEM) and Post 80 injection (Post80). Particle volume concentrations observed during DEM regenerations were much higher than those during Post80 regenerations, and the minimum air to fuel ratio achieved during the regenerations had little effect on particle emission for both strategies. This study provides valuable information for developing strategies that minimize the particle formation during active regenerations of NOx adsorbers.

  2. Aircraft observations of the physical and radiative properties of biomass aerosol particles during SAFARI-2000.

    NASA Astrophysics Data System (ADS)

    Osborne, S. R.; Haywood, J. M.

    2001-12-01

    An initial analysis will be shown from the ~80 h of data collected between 2--18 September 2000 by the UK Met Office C-130 aircraft during the dry season campaign of the Southern African Regional Science Initiative (SAFARI-2000). The talk will concentrate on the physical and optical properties of the biomass aerosol. The evolution of the particle size spectrum and its optical properties at emission and after ageing will be shown. The vertical distribution of the biomass plume over the land and sea will be compared in view of the local meteorology. A generalised three log-normal model is shown to represent aged biomass aerosol over the sea areas, both in terms of the number and mass particle size spectra, but also derived optical properties (e.g. asymmetry factor, single scatter albedo (ω 0) and extinction coefficient) as calculated using Mie theory and appropriate refractive indices. ω 0 was determined independently using a particle soot absorption photometer (giving the absorption coefficient at a wavelength of 0.567 μ m) and a nephelometer (giving the scattering coefficients at 0.45, 0.55 and 0.65 μ m). Good agreement was found between the measurements and those obtained from the Mie calculations and observed size distributions. A typical value of ω 0 at 0.55 μ m for aged biomass aerosol was 0.90. The radiative properties of the biomass aerosol over both land and sea will be summarised. Stratocumulus cloud was present on some of the days over the sea and the surprising lack of interaction between the elevated biomass plume (containing significant levels of cloud condensation nuclei) and the cloud capping the marine boundary layer will be illustrated. Using the cloud-free and cloudy case studies we can begin to elucidate the levels of direct and indirect forcing of the biomass aerosol on a regional scale. >http://www.mrfnet.demon.co.uk/africa/SAFARI2000.htm

  3. Extrapolating Ground-Based Aircraft Engine Exhaust Emissions to Cruise Conditions: Lessons From the 2013 ACCESS Chase Plane Experiment

    NASA Astrophysics Data System (ADS)

    Moore, R.; Shook, M.; Thornhill, K. L.; Winstead, E.; Anderson, B. E.

    2011-12-01

    Aircraft engine emissions constitute a tiny fraction of the global black carbon mass, but can have a disproportionate climatic impact because they are emitted high in the troposphere and in remote regions with otherwise low aerosol concentrations. Consequently, these particles are likely to strongly influence cirrus and contrail formation by acting as ice nuclei (IN). However, the ice nucleating properties of aircraft exhaust at relevant atmospheric conditions are not well known, and thus, the overall impact of aviation on cloud formation remains very uncertain. While a number of aircraft engine emissions studies have previously been conducted at sea level temperature and pressure (e.g., APEX, AAFEX-1 and 2), it unclear the extent to which exhaust emissions on the ground translate to emissions at cruise conditions with much lower inlet gas temperatures and pressures. To address this need, the NASA Alternative Fuel Effects on Contrails and Cruise Emissions (ACCESS) was conducted in February-April, 2013 to examine the aerosol and gas emissions from the NASA DC-8 under a variety of different fuel types, engine power, and altitude/meteorological conditions. Two different fuel types were studied: a traditional JP-8 fuel and a 50:50 blend of JP-8 and a camelina-based hydro-treated renewable jet (HRJ) fuel. Emissions were sampled using a comprehensive suite of gas- and aerosol-phase instrumentation integrated on an HU-25 Falcon jet that was positioned in the DC-8 exhaust plume at approximately 100-500m distance behind the engines. In addition, a four-hour ground test was carried out with sample probes positioned at 30 m behind each of the inboard engines. Measurements of aerosol concentration, size distribution, soot mass, and hygroscopicity were carried out along with trace gas measurements of CO2, NO, NO2, O3, and water vapor. NOx emissions were reconciled by employing the well-established Boeing method for normalizing engine fuel flow rates to STP; however, comparison

  4. Extrapolating Ground-Based Aircraft Engine Exhaust Emissions to Cruise Conditions: Lessons From the 2013 ACCESS Chase Plane Experiment

    NASA Astrophysics Data System (ADS)

    Moore, R.; Shook, M.; Thornhill, K. L.; Winstead, E.; Anderson, B. E.

    2013-12-01

    Aircraft engine emissions constitute a tiny fraction of the global black carbon mass, but can have a disproportionate climatic impact because they are emitted high in the troposphere and in remote regions with otherwise low aerosol concentrations. Consequently, these particles are likely to strongly influence cirrus and contrail formation by acting as ice nuclei (IN). However, the ice nucleating properties of aircraft exhaust at relevant atmospheric conditions are not well known, and thus, the overall impact of aviation on cloud formation remains very uncertain. While a number of aircraft engine emissions studies have previously been conducted at sea level temperature and pressure (e.g., APEX, AAFEX-1 and 2), it unclear the extent to which exhaust emissions on the ground translate to emissions at cruise conditions with much lower inlet gas temperatures and pressures. To address this need, the NASA Alternative Fuel Effects on Contrails and Cruise Emissions (ACCESS) was conducted in February-April, 2013 to examine the aerosol and gas emissions from the NASA DC-8 under a variety of different fuel types, engine power, and altitude/meteorological conditions. Two different fuel types were studied: a traditional JP-8 fuel and a 50:50 blend of JP-8 and a camelina-based hydro-treated renewable jet (HRJ) fuel. Emissions were sampled using a comprehensive suite of gas- and aerosol-phase instrumentation integrated on an HU-25 Falcon jet that was positioned in the DC-8 exhaust plume at approximately 100-500m distance behind the engines. In addition, a four-hour ground test was carried out with sample probes positioned at 30 m behind each of the inboard engines. Measurements of aerosol concentration, size distribution, soot mass, and hygroscopicity were carried out along with trace gas measurements of CO2, NO, NO2, O3, and water vapor. NOx emissions were reconciled by employing the well-established Boeing method for normalizing engine fuel flow rates to STP; however, comparison

  5. Forecast of jet engine exhaust emissions for future high altitude commercial aircraft

    NASA Technical Reports Server (NTRS)

    Grobman, J.; Ingebo, R. D.

    1974-01-01

    Projected minimum levels of engine exhaust emissions that may be practicably achievable for future commercial aircraft operating at high altitude cruise conditions are presented. The forecasts are based on: (1) current knowledge of emission characteristics of combustors and augmentors; (2) the current status of combustion research in emission reduction technology; (3) predictable trends in combustion systems and operating conditions as required for projected engine designs that are candidates for advanced subsonic or supersonic commercial aircraft. Results are presented for cruise conditions in terms of an emission index, g pollutant/kg fuel. Two sets of engine exhaust emission predictions are presented: the first, based on an independent NASA study and the second, based on the consensus of an ad hoc committee composed of industry, university, and government representatives. The consensus forecasts are in general agreement with the NASA forecasts.

  6. Aircraft measurements of trace gases and particles near the tropopause

    NASA Technical Reports Server (NTRS)

    Falconer, P.; Pratt, R.; Detwiler, A.; Chen, C. S.; Hogan, A.; Bernard, S.; Krebschull, K.; Winters, W.

    1983-01-01

    Research activities which were performed using atmospheric constituent data obtained by the NASA Global Atmospheric Sampling Program are described. The characteristics of the particle size spectrum in various meteorological settings from a special collection of GASP data are surveyed. The relationship between humidity and cloud particles is analyzed. Climatological and case studies of tropical ozone distributions measured on a large number of flights are reported. Particle counter calibrations are discussed as well as the comparison of GASP particle data in the upper troposphere with other measurements at lower altitudes over the Pacific Ocean.

  7. Effect of Friction Testing of Metals on Particle Emission

    NASA Astrophysics Data System (ADS)

    Kouam, J.; Songmene, V.; Djebara, A.; Khettabi, R.

    2012-06-01

    Metallic particles emitted during manufacturing processes can represent a serious danger for occupational safety. The mechanisms responsible for these particle emissions include two- and three-body frictions; Moreover, such particles can also be emitted during several other processes, including mechanical braking. To be in a position to devise ways to reduce these particle emissions at the source, it is important to know their size, quantity, and distribution, as well as the relationships between operating conditions and particle emissions. This article investigates nanoparticle and microparticle emissions during two friction tests: one (setup 1: pin in rotation only) simulates the friction occurring during mechanical braking actions, and another (setup 2: pin in rotation and translation) simulates the friction taking place at the tool-workpiece interface during metal cutting processes. The materials tested were aluminum alloys (6061-T6 and 7075-T6), and the pin used was a carbide cylinder. Particle emission was monitored using the Scanning Mobility Particle Sizer (SMPS) for nanoparticles, and the Aerosol Particle Sizer (APS) for microparticles. It was found that friction produces more nanoparticles than microparticles, and that total particle emission can be reduced by operating at low or at high sliding speeds.

  8. Thermodynamic correction of particle concentrations measured by underwing probes on fast flying aircraft

    NASA Astrophysics Data System (ADS)

    Weigel, R.; Spichtinger, P.; Mahnke, C.; Klingebiel, M.; Afchine, A.; Petzold, A.; Krämer, M.; Costa, A.; Molleker, S.; Jurkat, T.; Minikin, A.; Borrmann, S.

    2015-12-01

    Particle concentration measurements with underwing probes on aircraft are impacted by air compression upstream of the instrument body as a function of flight velocity. In particular for fast-flying aircraft the necessity arises to account for compression of the air sample volume. Hence, a correction procedure is needed to invert measured particle number concentrations to ambient conditions that is commonly applicable for different instruments to gain comparable results. In the compression region where the detection of particles occurs (i.e. under factual measurement conditions), pressure and temperature of the air sample are increased compared to ambient (undisturbed) conditions in certain distance away from the aircraft. Conventional procedures for scaling the measured number densities to ambient conditions presume that the particle penetration speed through the instruments' detection area equals the aircraft speed (True Air Speed, TAS). However, particle imaging instruments equipped with pitot-tubes measuring the Probe Air Speed (PAS) of each underwing probe reveal PAS values systematically below those of the TAS. We conclude that the deviation between PAS and TAS is mainly caused by the compression of the probed air sample. From measurements during two missions in 2014 with the German Gulfstream G-550 (HALO - High Altitude LOng range) research aircraft we develop a procedure to correct the measured particle concentration to ambient conditions using a thermodynamic approach. With the provided equation the corresponding concentration correction factor ξ is applicable to the high frequency measurements of each underwing probe which is equipped with its own air speed sensor (e.g. a pitot-tube). ξ-values of 1 to 0.85 are calculated for air speeds (i.e. TAS) between 60 and 260 m s-1. From HALO data it is found that ξ does not significantly vary between the different deployed instruments. Thus, for the current HALO underwing probe configuration a parameterisation of

  9. Energy and emissions saving potential of additive manufacturing: the case of lightweight aircraft components

    SciTech Connect

    Huang, Runze; Riddle, Matthew; Graziano, Diane; Warren, Joshua; Das, Sujit; Nimbalkar, Sachin; Cresko, Joe; Masanet, Eric

    2015-05-08

    Additive manufacturing (AM) holds great potential for improving materials efficiency, reducing life-cycle impacts, and enabling greater engineering functionality compared to conventional manufacturing (CM) processes. For these reasons, AM has been adopted by a growing number of aircraft component manufacturers to achieve more lightweight, cost-effective designs. This study estimates the net changes in life-cycle primary energy and greenhouse gas emissions associated with AM technologies for lightweight metallic aircraft components through the year 2050, to shed light on the environmental benefits of a shift from CM to AM processes in the U.S. aircraft industry. A systems modeling framework is presented, with integrates engineering criteria, life-cycle environmental data, and aircraft fleet stock and fuel use models under different AM adoption scenarios. Estimated fleetwide life-cycle primary energy savings in a rapid adoption scenario reach 70-174 million GJ/year in 2050, with cumulative savings of 1.2-2.8 billion GJ. Associated cumulative emission reduction potentials of CO2e were estimated at 92.8-217.4 million metric tons. About 95% of the savings is attributed to airplane fuel consumption reductions due to lightweighting. In addition, about 4050 tons aluminum, 7600 tons titanium and 8100 tons of nickel alloys could be saved per year in 2050. The results indicate a significant role of AM technologies in helping society meet its long-term energy use and GHG emissions reduction goals, and highlight barriers and opportunities for AM adoption for the aircraft industry.

  10. Do aircraft-based atmospheric observations indicate that anthropogenic methane emissions in the United States are larger than reported?

    NASA Astrophysics Data System (ADS)

    Kort, E. A.; Sweeney, C.; Andrews, A. E.; Dlugokencky, E. J.; Tans, P. P.; Hirsch, A.; Eluszkiewicz, J.; Nehrkorn, T.; Michalak, A. M.; Wofsy, S. C.

    2009-12-01

    Methane emissions over the United States are dominated by anthropogenic sources related to three major categories: fossil fuels (e.g. natural gas mining and distribution), landfills, and ruminants. Atmospheric signatures of these sources are evident in aircraft profiles, regularly showing enhancements of 50-100 ppb in the planetary boundary layer. Through a lagrangian particle dispersion model (LPDM), we directly link atmospheric methane measurements from NOAA’s aircraft program in 2004 with prior source fields, focusing on EDGAR32FT2000 and EDGARv4.0 for anthropogenic emissions. The LPDM employed is the Stochastic Time Inverted Lagrangian Transport model (STILT), driven by meteorological output from the Weather Research and Forecasting (WRF) model. Forward model runs indicate EDGAR32FT2000 is more consistent (despite larger point to point noise) with atmospheric data, particularly when assessing the shapes of vertical profiles, than EDGARv4.0. Simple scalar optimizations and inverse analyses suggest that emissions in the new EDGARv4.0 inventory, an inventory consistent with reported US EPA values, are too small.

  11. Aircraft emissions, plume chemistry, and alternative fuels: results from the APEX, AAFEX, and MDW-2009 campaigns

    NASA Astrophysics Data System (ADS)

    Wood, E. C.; Herndon, S. C.; Timko, M.; Yu, Z.; Miake-Lye, R. C.; Lee, B. H.; Santoni, G.; Munger, J. W.; Wofsy, S.; Anderson, B.; Knighton, W. B.

    2009-12-01

    We describe observations of aircraft emissions from the APEX, JETS-APEX2, APEX3, MDW-2009 and AAFEX campaigns. Direct emissions of HOx precursors are important for understanding exhaust plume chemistry due to their role in determining HOx concentrations. Nitrous acid (HONO) and formaldehyde are crucial HOx precursors and thus drivers of plume chemistry. At idle power, aircraft engine exhaust is unique among fossil fuel combustion sources due to the speciation of both NOx and VOCs. The impacts of emissions of HOx precursors on plume chemistry at low power are demonstrated with empirical observations of rapid NO to NO2 conversion, indicative of rapid HOx chemistry. The impacts of alternative fuels (derived from biomass, coal, and natural gas) on emissions of NOx, CO, and speciated VOCs are discussed.

  12. Measurement and Simulation of Volatile Particle Emissions from Military Aircraft

    DTIC Science & Technology

    2011-12-01

    HCs and Sulfate • Combustor system studies 0 1 km Carnegie Mellon University Team (WP-1626) • Measurement of PM in engine exhaust • Aging in “ smog ...Stratotanker CFM56-2B Engine Rake Inlet Heated Transfer Line Mobile Laboratory Smog Chamber WP-1626 Engine 1 m DR ~ 1 T ~ 500°C 250 m DR ~ 200 0 2 4 6 8...Dilution sampler, thermodenuder, and smog chamber techniques ● Archival Papers: 7 published, 4 near submission, others in process 25 Primary PM

  13. Detection of emission indices of aircraft exhaust compounds by open-path optical methods at airports

    NASA Astrophysics Data System (ADS)

    Schürmann, Gregor; Schäfer, Klaus; Jahn, Carsten; Hoffmann, Herbert; Utzig, Selina

    2005-10-01

    Air pollutant emission rates of aircrafts are determined with test bed measurements. Regulations exist for CO2, NO, NO2, CO concentrations, the content of total unburned hydrocarbons and the smoke number, a measure of soot. These emission indices are listed for each engine in a data base of the International Civil Aviation Organisation (ICAO) for four different Air pollutant emission rates of aircrafts are determined with test bed measurements. Regulations exist for CO2, NO, NO2, CO concentrations, the content of total unburned hydrocarbons and the smoke number, a measure of soot. These emission indices are listed for each engine in a data base of the International Civil Aviation Organisation (ICAO) for four different thrust levels (Idle, approach, cruise and take-off). It is a common procedure to use this data base as a starting point to estimate aircraft emissions at airports and further on to calculate the contribution of airports on local air quality. The comparison of these indices to real in use measurements therefore is a vital task to test the quality of air quality models at airports. Here a method to determine emission indices is used, where concentration measurements of CO2 together with other pollutants in the aircraft plume are needed. During intensive measurement campaigns at Zurich (ZRH) and Paris Charles De Gaulle (CDG) airports, concentrations of CO2, NO, NO2 and CO were measured. The measurement techniques were Fourier-Transform-Infrared (FTIR) spectrometry and Differential Optical Absorption Spectroscopy (DOAS). The big advantage of these methods is that no operations on the airport are influenced during measurement times. Together with detailed observations of taxiway movements, a comparison of emission indices with real in use emissions is possible.

  14. Multiple photon emission in heavy particle decays

    NASA Technical Reports Server (NTRS)

    Asakimori, K.; Burnett, T. H.; Cherry, M. L.; Christl, M. J.; Dake, S.; Derrickson, J. H.; Fountain, W. F.; Fuki, M.; Gregory, J. C.; Hayashi, T.

    1994-01-01

    Cosmic ray interactions, at energies above 1 TeV/nucleon, in emulsion chambers flown on high altitude balloons have yielded two events showing apparent decays of a heavy particle into one charged particle and four photons. The photons converted into electron pairs very close to the decay vertex. Attempts to explain this decay topology with known particle decays are presented. Unless both events represent a b yields u transition, which is statistically unlikely, then other known decay modes for charmed or bottom particles do not account satisfactorily for these observations. This could indicate, possibly, a new decay channel.

  15. Emission analysis of large number of various passenger electronic devices in aircraft

    NASA Astrophysics Data System (ADS)

    Schüür, Jens; Oppermann, Lukas; Enders, Achim; Nunes, Rafael R.; Oertel, Carl-Henrik

    2016-09-01

    The ever increasing use of PEDs (passenger or portable electronic devices) has put pressure on the aircraft industry as well as operators and administrations to reevaluate established restrictions in PED-use on airplanes in the last years. Any electronic device could cause electromagnetic interference to the electronics of the airplane, especially interference at receiving antennas of sensitive wireless navigation and communication (NAV/COM) systems. This paper presents a measurement campaign in an Airbus A320. 69 test passengers were asked to actively use a combination of about 150 electronic devices including many attached cables, preferentially with a high data load on their buses, to provoke maximal emissions. These emissions were analysed within the cabin as well as at the inputs of aircraft receiving antennas outside of the fuselage. The emissions of the electronic devices as well as the background noise are time-variant, so just comparing only one reference and one transmission measurement is not sufficient. Repeated measurements of both cases lead to a more reliable first analysis. Additional measurements of the absolute received power at the antennas of the airplane allow a good estimation of the real interference potential to aircraft NAV/COM systems. Although there were many measured emissions within the cabin, there were no disturbance signals detectable at the aircraft antennas.

  16. EPA Takes First Steps to Address Greenhouse Gas Emissions from Aircraft

    EPA Pesticide Factsheets

    (06/10/15 -ATLANTA) - The U.S. Environmental Protection Agency (EPA) is proposing to find under the Clean Air Act that greenhouse gas (GHG) emissions from commercial aircraft contribute to the pollution that causes climate change endangering the hea

  17. Particle emissions from diesel passenger cars equipped with a particle trap in comparison to other technologies.

    PubMed

    Mohr, Martin; Forss, Anna-Maria; Lehmann, Urs

    2006-04-01

    Tail pipe particle emissions of passenger cars, with different engine and aftertreatment technologies, were determined with special focus on diesel engines equipped with a particle filter. The particle number measurements were performed, during transient tests, using a condensation particle counter. The measurement procedure complied with the draft Swiss ordinance, which is based on the findings of the UN/ECE particulate measurement program. In addition, particle mass emissions were measured by the legislated and a modified filter method. The results demonstrate the high efficiency of diesel particle filters (DPFs) in curtailing nonvolatile particle emissions over the entire size range. Higher emissions were observed during short periods of DPF regeneration and immediately afterward, when a soot cake has not yet formed on the filter surface. The gasoline vehicles exhibited higher emissions than the DPF equipped diesel vehicles but with a large variation depending on the technology and driving conditions. Although particle measurements were carried out during DPF regeneration, it was impossible to quantify their contribution to the overall emissions, due to the wide variation in intensity and frequency of regeneration. The numbers counting method demonstrated its clear superiority in sensitivity to the mass measurement. The results strongly suggest the application of the particle number counting to quantify future low tailpipe emissions.

  18. An optical particle size spectrometer for aircraft-borne measurements in IAGOS-CARIBIC

    NASA Astrophysics Data System (ADS)

    Hermann, Markus; Weigelt, Andreas; Assmann, Denise; Pfeifer, Sascha; Muller, Thomas; Conrath, Thomas; Voigtlander, Jens; Heintzenberg, Jost; Wiedensohler, Alfred; Martinsson, Bengt G.; Deshler, Terry; Brenninkmeijer, Carl A. M.; Zahn, Andreas

    2016-05-01

    The particle number size distribution is an important parameter to characterize the atmospheric aerosol and its influence on the Earth's climate. Here we describe a new optical particle size spectrometer (OPSS) for measurements of the accumulation mode particle number size distribution in the tropopause region on board a passenger aircraft (IAGOS-CARIBIC observatory: In-service Aircraft for a Global Observing System - Civil Aircraft for Regular Investigation of the Atmosphere Based on an Instrument Container). A modified KS93 particle sensor from RION Co., Ltd., together with a new airflow system and a dedicated data acquisition system, is the key component of the CARIBIC OPSS. The instrument records individual particle pulse signal curves in the particle size range 130-1110 nm diameter (for a particle refractive index of 1.47-i0.006) together with a time stamp and thus allows the post-flight choice of the time resolution and the size distribution bin width. The CARIBIC OPSS has a 50 % particle detection diameter of 152 nm and a maximum asymptotic counting efficiency of 98 %. The instrument's measurement performance shows no pressure dependency and no particle coincidence for free tropospheric conditions. The size response function of the CARIBIC OPSS was obtained by a polystyrene latex calibration in combination with model calculations. Particle number size distributions measured with the new OPSS in the lowermost stratosphere agreed within a factor of 2 in concentration with balloon-borne measurements over western North America. Since June 2010 the CARIBIC OPSS is deployed once per month in the IAGOS-CARIBIC observatory.

  19. Aircraft

    DOEpatents

    Hibbs, B.D.; Lissaman, P.B.S.; Morgan, W.R.; Radkey, R.L.

    1998-09-22

    This disclosure provides a solar rechargeable aircraft that is inexpensive to produce, is steerable, and can remain airborne almost indefinitely. The preferred aircraft is a span-loaded flying wing, having no fuselage or rudder. Travelling at relatively slow speeds, and having a two-hundred foot wingspan that mounts photovoltaic cells on most all of the wing`s top surface, the aircraft uses only differential thrust of its eight propellers to turn. Each of five sections of the wing has one or more engines and photovoltaic arrays, and produces its own lift independent of the other sections, to avoid loading them. Five two-sided photovoltaic arrays, in all, are mounted on the wing, and receive photovoltaic energy both incident on top of the wing, and which is incident also from below, through a bottom, transparent surface. The aircraft is capable of a top speed of about ninety miles per hour, which enables the aircraft to attain and can continuously maintain altitudes of up to sixty-five thousand feet. Regenerative fuel cells in the wing store excess electricity for use at night, such that the aircraft can sustain its elevation indefinitely. A main spar of the wing doubles as a pressure vessel that houses hydrogen and oxygen gases for use in the regenerative fuel cell. The aircraft has a wide variety of applications, which include weather monitoring and atmospheric testing, communications, surveillance, and other applications as well. 31 figs.

  20. Aircraft

    DOEpatents

    Hibbs, Bart D.; Lissaman, Peter B. S.; Morgan, Walter R.; Radkey, Robert L.

    1998-01-01

    This disclosure provides a solar rechargeable aircraft that is inexpensive to produce, is steerable, and can remain airborne almost indefinitely. The preferred aircraft is a span-loaded flying wing, having no fuselage or rudder. Travelling at relatively slow speeds, and having a two-hundred foot wingspan that mounts photovoltaic cells on most all of the wing's top surface, the aircraft uses only differential thrust of its eight propellers to turn. Each of five sections of the wing has one or more engines and photovoltaic arrays, and produces its own lift independent of the other sections, to avoid loading them. Five two-sided photovoltaic arrays, in all, are mounted on the wing, and receive photovoltaic energy both incident on top of the wing, and which is incident also from below, through a bottom, transparent surface. The aircraft is capable of a top speed of about ninety miles per hour, which enables the aircraft to attain and can continuously maintain altitudes of up to sixty-five thousand feet. Regenerative fuel cells in the wing store excess electricity for use at night, such that the aircraft can sustain its elevation indefinitely. A main spar of the wing doubles as a pressure vessel that houses hydrogen and oxygen gasses for use in the regenerative fuel cell. The aircraft has a wide variety of applications, which include weather monitoring and atmospheric testing, communications, surveillance, and other applications as well.

  1. A personal sampler for aircraft engine cold start particles: laboratory development and testing.

    PubMed

    Armendariz, Alfredo; Leith, David

    2003-01-01

    Industrial hygienists in the U.S. Air Force are concerned about exposure of their personnel to jet fuel. One potential source of exposure for flightline ground crews is the plume emitted during the start of aircraft engines in extremely cold weather. The purpose of this study was to investigate a personal sampler, a small tube-and-wire electrostatic precipitator (ESP), for assessing exposure to aircraft engine cold start particles. Tests were performed in the laboratory to characterize the sampler's collection efficiency and to determine the magnitude of adsorption and evaporation artifacts. A low-temperature chamber was developed for the artifact experiments so tests could be performed at temperatures similar to actual field conditions. The ESP collected particles from 0.5 to 20 micro m diameter with greater than 98% efficiency at particle concentrations up to 100 mg/m(3). Adsorption artifacts were less than 5 micro g/m(3) when sampling a high concentration vapor stream. Evaporation artifacts were significantly lower for the ESP than for PVC membrane filters across a range of sampling times and incoming vapor concentrations. These tests indicate that the ESP provides more accurate exposure assessment results than traditional filter-based particle samplers when sampling cold start particles produced by an aircraft engine.

  2. Positron emission tracking of individual particles in particle-laden rimming flow

    SciTech Connect

    Denissenko, P. Thomas, P. J.; Guyez, E.; Parker, D. J.; Seville, J. P. K.

    2014-05-15

    The motion of a single tracer particle in particle-laden rimming flows is investigated experimentally by means of Positron Emission Particle Tracking (PEPT). Semi-dilute suspensions, with a volume fraction of 8% of heavy particles are considered. The trajectory of the tracer particle is monitored for several thousand cylinder revolutions and related to the optically recorded drift of the large-scale granular segregation bands developing in the cylinder. Results of the data analysis provide first insights into the relation between behaviour of individual particles and the spatiotemporal dynamics displayed by the macroscopic particle-segregation patterns.

  3. Effects of Alternative Fuels and Aromatics on Gas-Turbine Particle Emissions

    NASA Astrophysics Data System (ADS)

    Thornhill, K. L., II; Moore, R.; Winstead, E.; Anderson, B. E.; Klettlinger, J. L.; Ross, R. C.; Surgenor, A.

    2015-12-01

    This presentation describes experiments conducted with a Honeywell GTCP36-150 Auxiliary Power Unit (APU) to evaluate the effects of varying fuel composition on particle emissions. The APU uses a single-stage compressor stage, gas turbine engine with a can-type combustor to generate bypass flow and electrical power for supporting small aircraft and helicopters. It is installed in a "hush-house" at NASA Glenn Research Center and is configured as a stand-alone unit that can be fueled from an onboard tank or external supply. It operates at constant RPM, but its fuel flow can be varied by changing the electrical load or volume of bypass flow. For these tests, an external bank of resistors were attached to the APU's DC and AC electrical outlets and emissions measurements were made at low, medium and maximum electrical current loads. Exhaust samples were drawn from several points downstream in the exhaust duct and fed to an extensive suite of gas and aerosol sensors installed within a mobile laboratory parked nearby. Aromatic- and sulfur-free synthetic kerosenes from Rentech, Gevo, UOP, Amyris and Sasol were tested and their potential to reduce PM emissions evaluated against a single Jet A1 base fuel. The role of aromatic compounds in regulating soot emissions was also evaluated by adding metered amounts of aromatic blends (Aro-100, AF-Blend, SAK) and pure compounds (tetracontane and 1-methylnaphthalene) to a base alternative fuel (Sasol). Results show that, relative to Jet A1, alternative fuels reduce nonvolatile particle number emissions by 50-80% and--by virtue of producing much smaller particles—mass emissions by 65-90%; fuels with the highest hydrogen content produced the greatest reductions. Nonvolatile particle emissions varied in proportion to fuel aromatic content, with additives containing the most complex ring structures producing the greatest emission enhancements.

  4. Advanced combustion techniques for controlling NO/x/ emissions of high altitude cruise aircraft

    NASA Technical Reports Server (NTRS)

    Rudey, R. A.; Reck, G. M.

    1976-01-01

    An array of experiments have been and continue to be sponsored and conducted by NASA to explore the potential of advanced combustion techniques for controlling the emissions of aircraft into the upper atmosphere. Of particular concern are the oxides of nitrogen (NO/x/) emissions into the stratosphere. The experiments utilize a wide variety of approaches varying from advanced combustor concepts to fundamental flame tube experiments. Results are presented which indicate that substantial reductions in cruise NO/x/ emissions should be achievable in future aircraft engines. A major NASA program is described which focuses the many fundamental experiments into a planned evolution and demonstration of the prevaporized-premixed combustion technique in a full-scale engine.

  5. Performance, emissions, and physical characteristics of a rotating combustion aircraft engine

    NASA Technical Reports Server (NTRS)

    Berkowitz, M.; Hermes, W. L.; Mount, R. E.; Myers, D.

    1976-01-01

    The RC2-75, a liquid cooled two chamber rotary combustion engine (Wankel type), designed for aircraft use, was tested and representative baseline (212 KW, 285 BHP) performance and emissions characteristics established. The testing included running fuel/air mixture control curves and varied ignition timing to permit selection of desirable and practical settings for running wide open throttle curves, propeller load curves, variable manifold pressure curves covering cruise conditions, and EPA cycle operating points. Performance and emissions data were recorded for all of the points run. In addition to the test data, information required to characterize the engine and evaluate its performance in aircraft use is provided over a range from one half to twice its present power. The exhaust emissions results are compared to the 1980 EPA requirements. Standard day take-off brake specific fuel consumption is 356 g/KW-HR (.585 lb/BHP-HR) for the configuration tested.

  6. Status review of NASA programs for reducing aircraft gas turbine engine emissions

    NASA Technical Reports Server (NTRS)

    Rudey, R. A.

    1976-01-01

    The paper describes and discusses the results from some of the research and development programs for reducing aircraft gas turbine engine emissions. Although the paper concentrates on NASA programs only, work supported by other U.S. government agencies and industry has provided considerable data on low emission advanced technology for aircraft gas turbine engine combustors. The results from the two major NASA technology development programs, the ECCP (Experimental Clean Combustor Program) and the PRTP (Pollution Reduction Technology Program), are presented and compared with the requirements of the 1979 U.S. EPA standards. Emission reduction techniques currently being evaluated in these programs are described along with the results and a qualitative assessment of development difficulty.

  7. Scheduled Civil Aircraft Emission Inventories for 1976 and 1984: Database Development and Analysis

    NASA Technical Reports Server (NTRS)

    Baughcum, Steven L.; Henderson, Stephen C.; Tritz, Terrance G.

    1996-01-01

    This report describes the development of a three-dimensional database of aircraft fuel burn and emissions (fuel burned, NOx, CO, and hydrocarbons) from scheduled commercial aircraft for four months (February, May, August, and November) of 1976 and 1984. Combining this data with earlier published data for 1990 and 1992, trend analyses for fuel burned, NOx, carbon monoxide, and hydrocarbons were calculated for selected regions (global, North America, Europe, North Atlantic, and North Pacific). These emissions inventories are available for use by atmospheric scientists conducting the Atmospheric Effects of Aviation Project (AEAP) modeling studies. Fuel burned and emissions of nitrogen oxides (NOx as NO2), carbon monoxide, and hydrocarbons have been calculated on a 1 degree latitude x 1 degree longitude x 1 kilometer altitude grid and delivered to NASA as electronic files.

  8. Air Force F-16 Aircraft Engine Aerosol Emissions Under Cruise Altitude Conditions

    NASA Technical Reports Server (NTRS)

    Anderson, Bruce E.; Cofer, W. Randy, III; McDougal, David S.

    1999-01-01

    Selected results from the June 1997 Third Subsonic Assessment Near-Field Interactions Flight (SNIF-III) Experiment are documented. The primary objectives of the SNIF-III experiment were to determine the partitioning and abundance of sulfur species and to examine the formation and growth of aerosol particles in the exhaust of F-16 aircraft as a function of atmospheric and aircraft operating conditions and fuel sulfur concentration. This information is, in turn, being used to address questions regarding the fate of aircraft fuel sulfur impurities and to evaluate the potential of their oxidation products to perturb aerosol concentrations and surface areas in the upper troposphere. SNIF-III included participation of the Vermont and New Jersey Air National Guard F-16's as source aircraft and the Wallops Flight Facility T-39 Sabreliner as the sampling platform. F-16's were chosen as a source aircraft because they are powered by the modern F-100 Series 220 engine which is projected to be representative of future commercial aircraft engine technology. The T-39 instrument suite included sensors for measuring volatile and non-volatile condensation nuclei (CN), aerosol size distributions over the range from 0.1 to 3.0 (micro)m, 3-D winds, temperature, dewpoint, carbon dioxide (CO2), sulfur dioxide (SO2), sulfuric acid (H2SO4), and nitric acid (HNO3).

  9. Thermodynamic correction of particle concentrations measured by underwing probes on fast-flying aircraft

    NASA Astrophysics Data System (ADS)

    Weigel, Ralf; Spichtinger, Peter; Mahnke, Christoph; Klingebiel, Marcus; Afchine, Armin; Petzold, Andreas; Krämer, Martina; Costa, Anja; Molleker, Sergej; Reutter, Philipp; Szakáll, Miklós; Port, Max; Grulich, Lucas; Jurkat, Tina; Minikin, Andreas; Borrmann, Stephan

    2016-10-01

    Particle concentration measurements with underwing probes on aircraft are impacted by air compression upstream of the instrument body as a function of flight velocity. In particular, for fast-flying aircraft the necessity arises to account for compression of the air sample volume. Hence, a correction procedure is needed to invert measured particle number concentrations to ambient conditions that is commonly applicable to different instruments to gain comparable results. In the compression region where the detection of particles occurs (i.e. under factual measurement conditions), pressure and temperature of the air sample are increased compared to ambient (undisturbed) conditions in certain distance away from the aircraft. Conventional procedures for scaling the measured number densities to ambient conditions presume that the air volume probed per time interval is determined by the aircraft speed (true air speed, TAS). However, particle imaging instruments equipped with pitot tubes measuring the probe air speed (PAS) of each underwing probe reveal PAS values systematically below those of the TAS. We conclude that the deviation between PAS and TAS is mainly caused by the compression of the probed air sample. From measurements during two missions in 2014 with the German Gulfstream G-550 (HALO - High Altitude LOng range) research aircraft we develop a procedure to correct the measured particle concentration to ambient conditions using a thermodynamic approach. With the provided equation, the corresponding concentration correction factor ξ is applicable to the high-frequency measurements of the underwing probes, each of which is equipped with its own air speed sensor (e.g. a pitot tube). ξ values of 1 to 0.85 are calculated for air speeds (i.e. TAS) between 60 and 250 m s-1. For different instruments at individual wing position the calculated ξ values exhibit strong consistency, which allows for a parameterisation of ξ as a function of TAS for the current HALO

  10. An automatic isokinetic sampler for particulate emissions from aircraft gas turbine engines. Final report Feb 75-Jun 78

    SciTech Connect

    Dehne, H.

    1980-01-01

    An automated isokinetic sampler for evaluating particulate emissions from aircraft gas turbine engines was designed, constructed and tested. The sampler is capable of collecting the particulate mass emitted by an aircraft gas turbine at the exit plane (non-afterburner operation) for gravimetric measurements and permits simultaneous on-line particle size distribution measurements to be performed. The particulate is collected on a fiber glass filter for gravimetric measurement. The size distribution is determined by conditioning the gas turbine exhaust gases and passing them through a mobility particulate size distribution analyzer. The sampler has two-axis traverse capability and a maximum sampling capability of 226 1/min (8 scfm). Test data are automatically recorded. Control of the sampler is by means of 12-bit microprocessor. Preliminary tests were performed at the Naval Air Rework Facility, Alameda, California, at various construction stages of the sampler to evaluate its performance and to measure the effects of fuel additives on particulate emissions on a TF41 gas turbine engine.

  11. Ethanol emission from loose corn silage and exposed silage particles

    NASA Astrophysics Data System (ADS)

    Hafner, Sasha D.; Montes, Felipe; Rotz, C. Alan; Mitloehner, Frank

    2010-11-01

    Silage on dairy farms has been identified as a major source of volatile organic compound (VOC) emissions. However, rates of VOC emission from silage are not accurately known. In this work, we measured ethanol (a dominant silage VOC) emission from loose corn silage and exposed corn silage particles using wind tunnel systems. Flux of ethanol was highest immediately after exposing loose silage samples to moving air (as high as 220 g m -2 h -1) and declined by as much as 76-fold over 12 h as ethanol was depleted from samples. Emission rate and cumulative 12 h emission increased with temperature, silage permeability, exposed surface area, and air velocity over silage samples. These responses suggest that VOC emission from silage on farms is sensitive to climate and management practices. Ethanol emission rates from loose silage were generally higher than previous estimates of total VOC emission rates from silage and mixed feed. For 15 cm deep loose samples, mean cumulative emission was as high as 170 g m -2 (80% of initial ethanol mass) after 12 h of exposure to an air velocity of 5 m s -1. Emission rates measured with an emission isolation flux chamber were lower than rates measured in a wind tunnel and in an open setting. Results show that the US EPA emission isolation flux chamber method is not appropriate for estimating VOC emission rates from silage in the field.

  12. Exoelectronic emission of particles of lunar surface material

    NASA Technical Reports Server (NTRS)

    Mints, R. I.; Alimov, V. I.; Melekhin, V. P.; Milman, I. I.; Kryuk, V. I.; Kunin, L. L.; Tarasov, L. S.

    1974-01-01

    A secondary electron multiplier was used to study the thermostimulated exoelectronic emission of particles of lunar surface material returned by the Soviet Luna 16 automatic station. The natural exoemission from fragments of slag, glass, anorthosite, and a metallic particle was recorded in the isochronic and isothermal thermostimulation regimes. The temperature of emission onset depended on the type of regolith fragment. For the first three particles the isothermal drop in emission is described by first-order kinetic equations. For the anorthosite fragment, exoemission at constant temperature is characterized by a symmetric curve with a maximum. These data indicate the presence of active surface defects, whose nature can be due to the prehistory of the particles.

  13. Particle Acceleration and Associated Emission from Relativistic Shocks

    NASA Technical Reports Server (NTRS)

    Nishkawa, Ken-Ichi

    2009-01-01

    Five talks consist of a research program consisting of numerical simulations and theoretical development designed to provide an understanding of the emission from accelerated particles in relativistic shocks. The goal of this lecture is to discuss the particle acceleration, magnetic field generation, and radiation along with the microphysics of the shock process in a self-consistent manner. The discussion involves the collisionless shocks that produce emission from gamma-ray bursts and their afterglows, and producing emission from supernova remnants and AGN relativistic jets. Recent particle-in-cell simulation studies have shown that the Weibel (mixed mode two-stream filamentation) instability is responsible for particle (electron, positron, and ion) acceleration and magnetic field generation in relativistic collisionless shocks. 3-D RPIC code parallelized with MPI has been used to investigate the dynamics of collisionless shocks in electron-ion and electron-positron plasmas with and without initial ambient magnetic fields. In this lecture we will present brief tutorials of RPIC simulations and RMHD simulations, a brief summary of recent RPIC simulations, mechanisms of particle acceleration in relativistic shocks, and calculation of synchrotron radiation by tracing particles. We will discuss on emission from the collisionless shocks, which will be calculated during the simulation by tracing particle acceleration self-consistently in the inhomogeneous magnetic fields generated in the shocks. In particular, we will discuss the differences between standard synchrotron radiation and the jitter radiation that arises in turbulent magnetic fields.

  14. Particle Acceleration and Emission in Relativistic Jets

    NASA Technical Reports Server (NTRS)

    Nishikawa, K.; Hardee, P. E.; Richardson, G. A.; Preece, R. D.; Sol, H.; Fishman, G. J.

    2003-01-01

    Shock wave acceleration is an ubiquitous phenomenon in astrophysical plasmas. Plasma waves and their associated instabilities (e.g., the Buneman instability, two-streaming instability, and the Weibel instability) created in the shocks are responsible for particle (electron, positron, and ion) acceleration. Using a 3-D relativistic electromagnetic particle (REMP) code, we have investigated particle acceleration associated with a relativistic jet front propagating through an ambient plasma with and without initial magnetic fields. We find only small differences in the results between no ambient and weak ambient magnetic fields. Simulations show that the Weibel instability created in the collisionless shock front accelerates particles perpendicular and parallel to the jet propagation direction. While some Fermi acceleration may occur at the jet front, the majority of electron acceleration takes place behind the jet front and cannot be characterized as Fermi acceleration. The simulation results show that this instability is responsible for generating and amplifying highly nonuniform, small-scale magnetic fields, which contribute to the electron's transverse deflection behind the jet head. The 'jitter' radiation from deflected electrons has different properties than synchrotron radiation which is calculated in a uniform magnetic field. This jitter radiation may be important to understanding the complex time evolution and/or spectral structure in gamma-ray bursts, relativistic jets, and supernova remnants.

  15. Acoustic emission fatigue crack monitoring of a simulated aircraft fuselage structure

    NASA Astrophysics Data System (ADS)

    Lucas, Jeremy James

    The purpose of this research was to replicate the fatigue cracking that occurs in aircraft placed under loads from cyclical compression and decompression. As a fatigue crack grows, it releases energy in the form of acoustic emissions. These emissions are transmitted through the structure in waves, which can be recorded using acoustic emission (AE) transducers. This research employed a pressure vessel constructed out of aluminum and placed under cyclical loads at 1 Hz in order to simulate the loads placed on an aircraft fuselage in flight. The AE signals were recorded by four resonant AE transducers. These were placed on the pressure vessel such that it was possible to determine the location of each AE signal. These signals were then classified using a Kohonen self organizing map (SOM) neural network. By using proper data filtering before the SOM was run and using the correct classification parameters, it was shown that this is a highly accurate method of classifying AE waveforms from fatigue crack growth. This initial classification was done using AE waveform quantification parameters. The method was then validated by using both source location and then examining the waveforms in order to ensure that the waveforms classified into each category were the expected waveform types associated with each of the AE sources. Thus, acoustic emission nondestructive testing (NDT), in combination with a SOM neural network, proved to be an excellent means of fatigue crack growth monitoring in a simulated aluminum aircraft structure.

  16. Combustion Dynamics and Control for Ultra Low Emissions in Aircraft Gas-Turbine Engines

    NASA Technical Reports Server (NTRS)

    DeLaat, John C.

    2011-01-01

    Future aircraft engines must provide ultra-low emissions and high efficiency at low cost while maintaining the reliability and operability of present day engines. The demands for increased performance and decreased emissions have resulted in advanced combustor designs that are critically dependent on efficient fuel/air mixing and lean operation. However, all combustors, but most notably lean-burning low-emissions combustors, are susceptible to combustion instabilities. These instabilities are typically caused by the interaction of the fluctuating heat release of the combustion process with naturally occurring acoustic resonances. These interactions can produce large pressure oscillations within the combustor and can reduce component life and potentially lead to premature mechanical failures. Active Combustion Control which consists of feedback-based control of the fuel-air mixing process can provide an approach to achieving acceptable combustor dynamic behavior while minimizing emissions, and thus can provide flexibility during the combustor design process. The NASA Glenn Active Combustion Control Technology activity aims to demonstrate active control in a realistic environment relevant to aircraft engines by providing experiments tied to aircraft gas turbine combustors. The intent is to allow the technology maturity of active combustion control to advance to eventual demonstration in an engine environment. Work at NASA Glenn has shown that active combustion control, utilizing advanced algorithms working through high frequency fuel actuation, can effectively suppress instabilities in a combustor which emulates the instabilities found in an aircraft gas turbine engine. Current efforts are aimed at extending these active control technologies to advanced ultra-low-emissions combustors such as those employing multi-point lean direct injection.

  17. Aircraft engine exhaust emissions and other airport-related contributions to ambient air pollution: A review

    NASA Astrophysics Data System (ADS)

    Masiol, Mauro; Harrison, Roy M.

    2014-10-01

    Civil aviation is fast-growing (about +5% every year), mainly driven by the developing economies and globalisation. Its impact on the environment is heavily debated, particularly in relation to climate forcing attributed to emissions at cruising altitudes and the noise and the deterioration of air quality at ground-level due to airport operations. This latter environmental issue is of particular interest to the scientific community and policymakers, especially in relation to the breach of limit and target values for many air pollutants, mainly nitrogen oxides and particulate matter, near the busiest airports and the resulting consequences for public health. Despite the increased attention given to aircraft emissions at ground-level and air pollution in the vicinity of airports, many research gaps remain. Sources relevant to air quality include not only engine exhaust and non-exhaust emissions from aircraft, but also emissions from the units providing power to the aircraft on the ground, the traffic due to the airport ground service, maintenance work, heating facilities, fugitive vapours from refuelling operations, kitchens and restaurants for passengers and operators, intermodal transportation systems, and road traffic for transporting people and goods in and out to the airport. Many of these sources have received inadequate attention, despite their high potential for impact on air quality. This review aims to summarise the state-of-the-art research on aircraft and airport emissions and attempts to synthesise the results of studies that have addressed this issue. It also aims to describe the key characteristics of pollution, the impacts upon global and local air quality and to address the future potential of research by highlighting research needs.

  18. Developing particle emission inventories using remote sensing (PEIRS).

    PubMed

    Tang, Chia-Hsi; Coull, Brent A; Schwartz, Joel; Lyapustin, Alexei I; Di, Qian; Koutrakis, Petros

    2017-01-01

    Information regarding the magnitude and distribution of PM2.5 emissions is crucial in establishing effective PM regulations and assessing the associated risk to human health and the ecosystem. At present, emission data is obtained from measured or estimated emission factors of various source types. Collecting such information for every known source is costly and time-consuming. For this reason, emission inventories are reported periodically and unknown or smaller sources are often omitted or aggregated at large spatial scale. To address these limitations, we have developed and evaluated a novel method that uses remote sensing data to construct spatially resolved emission inventories for PM2.5. This approach enables us to account for all sources within a fixed area, which renders source classification unnecessary. We applied this method to predict emissions in the northeastern United States during the period 2002-2013 using high-resolution 1 km × 1 km aerosol optical depth (AOD). Emission estimates moderately agreed with the EPA National Emission Inventory (R(2) = 0.66-0.71, CV = 17.7-20%). Predicted emissions are found to correlate with land use parameters, suggesting that our method can capture emissions from land-use-related sources. In addition, we distinguished small-scale intra-urban variation in emissions reflecting distribution of metropolitan sources. In essence, this study demonstrates the great potential of remote sensing data to predict particle source emissions cost-effectively.

  19. A Low LET Radiation Spectrometer for Measuring Particle Doses in Space and Aircraft

    NASA Technical Reports Server (NTRS)

    Stassinopoulos, E. G.; Stauffer, C. A.; Brucker, G. J.; Dachev, T. P.; Day, John H. (Technical Monitor)

    2002-01-01

    This paper presents experimental data that demonstrates the feasibility of fabricating a miniature nuclear particle dosimeter for monitoring doses in aircraft and satellites. The basic instrument is a Low Linear-Energy-Transfer (LET) Radiation Spectrometer (LoLRS) that is designed to measure the energy deposited by particles with low LET values. The heart of the instrument is a Silicon-Lithium Drifted Diode (SLDD). Test results show that the LoLRS can be used to monitor the radiation threat to personnel in flights of space- and aircraft and also to generate a comprehensive data base from aviation and satellite measurements that can contribute to the formulation of more accurate environmental radiation models for dose predictions with reduced uncertainty factors.

  20. Evaluation of a Hydrogen Fuel Cell Powered Blended-Wing-Body Aircraft Concept for Reduced Noise and Emissions

    NASA Technical Reports Server (NTRS)

    Guynn, Mark D.; Freh, Joshua E.; Olson, Erik D.

    2004-01-01

    This report describes the analytical modeling and evaluation of an unconventional commercial transport aircraft concept designed to address aircraft noise and emission issues. A blended-wing-body configuration with advanced technology hydrogen fuel cell electric propulsion is considered. Predicted noise and emission characteristics are compared to a current technology conventional configuration designed for the same mission. The significant technology issues which have to be addressed to make this concept a viable alternative to current aircraft designs are discussed. This concept is one of the "Quiet Green Transport" aircraft concepts studied as part of NASA's Revolutionary Aerospace Systems Concepts (RASC) Program. The RASC Program was initiated to develop revolutionary concepts that address strategic objectives of the NASA Enterprises, such as reducing aircraft noise and emissions, and to identify advanced technology requirements for the concepts.

  1. Evaluation of an Aircraft Concept With Over-Wing, Hydrogen-Fueled Engines for Reduced Noise and Emissions

    NASA Technical Reports Server (NTRS)

    Guynn, Mark D.; Olson, Erik D.

    2002-01-01

    This report describes the analytical modeling and evaluation of an unconventional commercial transport aircraft concept designed to address aircraft noise and emission issues. A strut-braced wing configuration with overwing, ultra-high bypass ratio, hydrogen fueled turbofan engines is considered. Estimated noise and emission characteristics are compared to a conventional configuration designed for the same mission and significant benefits are identified. The design challenges and technology issues which would have to be addressed to make the concept a viable alternative to current aircraft designs are discussed. This concept is one of the "Quiet Green Transport" aircraft concepts studied as part of NASA's Revolutionary Aerospace Systems Concepts (RASC) Program. The RASC Program seeks to develop revolutionary concepts that address strategic objectives of the NASA Enterprises, such as reducing aircraft noise and emissions, and to identify enabling advanced technology requirements for the concepts.

  2. Energy and emissions saving potential of additive manufacturing: the case of lightweight aircraft components

    DOE PAGES

    Huang, Runze; Riddle, Matthew; Graziano, Diane; ...

    2015-05-08

    Additive manufacturing (AM) holds great potential for improving materials efficiency, reducing life-cycle impacts, and enabling greater engineering functionality compared to conventional manufacturing (CM) processes. For these reasons, AM has been adopted by a growing number of aircraft component manufacturers to achieve more lightweight, cost-effective designs. This study estimates the net changes in life-cycle primary energy and greenhouse gas emissions associated with AM technologies for lightweight metallic aircraft components through the year 2050, to shed light on the environmental benefits of a shift from CM to AM processes in the U.S. aircraft industry. A systems modeling framework is presented, with integratesmore » engineering criteria, life-cycle environmental data, and aircraft fleet stock and fuel use models under different AM adoption scenarios. Estimated fleetwide life-cycle primary energy savings in a rapid adoption scenario reach 70-174 million GJ/year in 2050, with cumulative savings of 1.2-2.8 billion GJ. Associated cumulative emission reduction potentials of CO2e were estimated at 92.8-217.4 million metric tons. About 95% of the savings is attributed to airplane fuel consumption reductions due to lightweighting. In addition, about 4050 tons aluminum, 7600 tons titanium and 8100 tons of nickel alloys could be saved per year in 2050. The results indicate a significant role of AM technologies in helping society meet its long-term energy use and GHG emissions reduction goals, and highlight barriers and opportunities for AM adoption for the aircraft industry.« less

  3. Estimates of non-traditional secondary organic aerosols from aircraft SVOC and IVOC emissions using CMAQ

    NASA Astrophysics Data System (ADS)

    Woody, M. C.; West, J. J.; Jathar, S. H.; Robinson, A. L.; Arunachalam, S.

    2015-06-01

    Utilizing an aircraft-specific parameterization based on smog chamber data in the Community Multiscale Air Quality (CMAQ) model with the volatility basis set (VBS), we estimated contributions of non-traditional secondary organic aerosols (NTSOA) for aircraft emissions during landing and takeoff (LTO) activities at the Hartsfield-Jackson Atlanta International Airport. NTSOA, formed from the oxidation of semi-volatile and intermediate volatility organic compounds (S/IVOCs), is a heretofore unaccounted component of fine particulate matter (PM2.5) in most air quality models. We expanded a prerelease version of CMAQ with VBS implemented for the Carbon Bond 2005 (CB05) chemical mechanism to use the Statewide Air Pollution Research Center 2007 (SAPRC-07) chemical mechanism and added species representing aircraft S/IVOCs and corresponding NTSOA oxidation products. Results indicated that the maximum monthly average NTSOA contributions occurred at the airport and ranged from 2.4 ng m-3 (34 % from idle and 66 % from non-idle aircraft activities) in January to 9.1 ng m-3 (33 and 67 %) in July. This represents 1.7 % (of 140 ng m-3) in January and 7.4 % in July (of 122 ng m-3) of aircraft-attributable PM2.5 compared to 41.0-42.0 % from elemental carbon and 42.8-58.0 % from inorganic aerosols. As a percentage of PM2.5, impacts were higher downwind of the airport, where NTSOA averaged 4.6-17.9 % of aircraft-attributable PM2.5 and, considering alternative aging schemes, was as high as 24.0 % - thus indicating the increased contribution of aircraft-attributable SOA as a component of PM2.5. However, NTSOA contributions were generally low compared to smog chamber results, particularly at idle, due to the considerably lower ambient organic aerosol concentrations in CMAQ compared to those in the smog chamber experiments.

  4. Estimates of non-traditional secondary organic aerosols from aircraft SVOC and IVOC emissions using CMAQ

    NASA Astrophysics Data System (ADS)

    Woody, M. C.; West, J. J.; Jathar, S. H.; Robinson, A. L.; Arunachalam, S.

    2014-12-01

    Utilizing an aircraft-specific parameterization based on smog chamber data in the Community Multiscale Air Quality (CMAQ) model with the Volatility Basis Set (VBS), we estimated contributions of non-traditional secondary organic aerosols (NTSOA) for aircraft emissions during landing and takeoff (LTO) activities at the Hartsfield-Jackson Atlanta International Airport. NTSOA, formed from the oxidation of semi-volatile and intermediate volatility organic compounds (S/IVOCs), is a heretofore unaccounted component of fine particulate matter (PM2.5) in most air quality models. We expanded a prerelease version of CMAQ with VBS implemented for the Carbon Bond 2005 (CB05) chemical mechanism to use the Statewide Air Pollution Research Center 2007 (SAPRC-07) chemical mechanism, and added species representing aircraft S/IVOCs and corresponding NTSOA oxidation products. Results indicated the maximum monthly average NTSOA contributions occurred at the airport, and ranged from 2.4 ng m-3 (34% from idle and 66% from non-idle aircraft activities) in January to 9.1 ng m-3 (33 and 67%) in July. This represents 1.7% (of 140 ng m-3) in January and 7.4% in July (of 122 ng m-3) of aircraft-attributable PM2.5, compared to 41.0-42.0% from elemental carbon and 42.8-58.0% from inorganic aerosols. As a percentage of PM2.5, impacts were higher downwind of the airport, where NTSOA averaged 4.6-17.9% of aircraft-attributable PM2.5 and, considering alternative aging schemes, was high as 24.0% - thus indicating the increased contribution of aircraft-attributable SOA, as a component of PM2.5. However, NTSOA contributions were generally low compared to smog chamber results, particularly at idle, due to the considerably lower ambient organic aerosol concentrations in CMAQ, vs. those in the smog chamber experiments.

  5. Eastern Asian Emissions of Anthropogenic Halocarbons Deduced from Aircraft Concentration Data

    NASA Technical Reports Server (NTRS)

    Palmer, Paul I.; Jacob, Daniel J.; Mickle, Loretta, J.; Blake, Donald R.; Sachse, Glen W.; Fuelberg, Henry E.; Kiley, Christopher M.

    2003-01-01

    The Montreal Protocol restricts production of ozone-depleting halocarbons worldwide. Enforcement of the protocol has relied mainly on annual government statistics of production and consumption of these compounds (bottom-up approach). We show here that aircraft observations of ha1ocarbon:CO enhancement ratios on regional to continental scales can be used to infer halocarbon emissions, providing independent verification of the bottom-up approach. We apply this topdown approach to aircraft observations of Asian outflow &om the TRACE-P mission over the western Pacific (March-April 2001) and derive emissions from eastern Asia (China, Japan, and Korea). We derive an eastern Asian carbon tetrachloride (CCl4) source of 21.5 Gg yr(sup -1), several-fold larger than previous estimates and amounting to -30% of the global budget for this gas. Our emission estimate for CFC-11 from eastern Asia is 50% higher than inventories derived from manufacturing records. Our emission estimates for methyl chloroform (CH3CC13) and CFC-12 are in agreement with existing inventories. For halon 1211 we find only a strong local source originating from the Shanghai area. Our emission estimates for the above gases result in a approximately equal to 40% increase in the ozone depletion potential (ODP) of Asian emissions relative to previous estimates, corresponding to a approximately equal to 10% global increase in ODP.

  6. Hydrocarbon emissions from in-use commercial aircraft during airport operations.

    PubMed

    Herndon, Scott C; Rogers, Todd; Dunlea, Edward J; Jayne, John T; Miake-Lye, Richard; Knighton, Berk

    2006-07-15

    The emissions of selected hydrocarbons from in-use commercial aircraft at a major airport in the United States were characterized using proton-transfer reaction mass spectrometry (PTR-MS) and tunable infrared differential absorption spectroscopy (TILDAS) to probe the composition of diluted exhaust plumes downwind. The emission indices for formaldehyde, acetaldehyde, benzene, and toluene, as well as other hydrocarbon species, were determined through analysis of 45 intercepted plumes identified as being associated with specific aircraft. As would have been predicted for high bypass turbine engines, the hydrocarbon emission index was greater in idle and taxiway acceleration plumes relative to approach and takeoff plumes. The opposite was seen in total NOy emission index, which increased from idle to takeoff. Within the idle plumes sampled in this study, the median emission index for formaldehyde was 1.1 g of HCHO per kg of fuel. For the subset of hydrocarbons measured in this work, the idle emissions levels relative to formaldehyde agree well with those of previous studies. The projected total unburned hydrocarbons (UHC) deduced from the range of in-use idle plumes analyzed in this work is greater than a plausible range of engine types using the defined idle condition (7% of rated engine thrust) in the International Civil Aviation Organization (ICAO) databank reference.

  7. Near-Field Characterization of Methane Emission Variability from a Compressor Station Using a Model Aircraft.

    PubMed

    Nathan, Brian J; Golston, Levi M; O'Brien, Anthony S; Ross, Kevin; Harrison, William A; Tao, Lei; Lary, David J; Johnson, Derek R; Covington, April N; Clark, Nigel N; Zondlo, Mark A

    2015-07-07

    A model aircraft equipped with a custom laser-based, open-path methane sensor was deployed around a natural gas compressor station to quantify the methane leak rate and its variability at a compressor station in the Barnett Shale. The open-path, laser-based sensor provides fast (10 Hz) and precise (0.1 ppmv) measurements of methane in a compact package while the remote control aircraft provides nimble and safe operation around a local source. Emission rates were measured from 22 flights over a one-week period. Mean emission rates of 14 ± 8 g CH4 s(-1) (7.4 ± 4.2 g CH4 s(-1) median) from the station were observed or approximately 0.02% of the station throughput. Significant variability in emission rates (0.3-73 g CH4 s(-1) range) was observed on time scales of hours to days, and plumes showed high spatial variability in the horizontal and vertical dimensions. Given the high spatiotemporal variability of emissions, individual measurements taken over short durations and from ground-based platforms should be used with caution when examining compressor station emissions. More generally, our results demonstrate the unique advantages and challenges of platforms like small unmanned aerial vehicles for quantifying local emission sources to the atmosphere.

  8. Mechanisms of Increased Particle and VOC Emissions during DPF Active Regeneration and Practical Emissions Considering Regeneration.

    PubMed

    Yamada, Hiroyuki; Inomata, Satoshi; Tanimoto, Hiroshi

    2017-03-07

    Mechanisms involved in increased particle and volatile organic compound (VOC) emissions during active and parked active regenerations of a diesel particulate filter (DPF) were investigated using heavy-duty trucks equipped with both a urea selective catalytic reduction system and a DPF (SCR + DPF) and a DPF-only. Particle emissions increased in the later part of the regeneration period but the mechanisms were different above and below 23 nm. Particles above 23 nm were emitted due to the lower filtering efficiency of the DPF because of the decreasing amount of soot trapped during regeneration. Small particles below 23 nm were thought to be mainly sulfuric acid particles produced from SO2 trapped by the catalyst, being released and oxidized during regeneration. Contrary to the particle emissions, VOCs increased in the earlier part of the regeneration period. The mean molecular weights of the VOCs increased gradually as the regeneration proceeded. To evaluate "practical emissions" in which increased emissions during the regeneration were considered, a Regeneration Correction Factor (RCF), which is the average emission during one cycle of regeneration/emission in normal operation, was adopted. The RCFs of PM and VOCs were 1.1-1.5, and those of PNs were as high as 3-140, although they were estimated from a limited number of observations.

  9. Assessing the environmental impacts of aircraft noise and emissions

    NASA Astrophysics Data System (ADS)

    Mahashabde, Anuja; Wolfe, Philip; Ashok, Akshay; Dorbian, Christopher; He, Qinxian; Fan, Alice; Lukachko, Stephen; Mozdzanowska, Aleksandra; Wollersheim, Christoph; Barrett, Steven R. H.; Locke, Maryalice; Waitz, Ian A.

    2011-01-01

    With the projected growth in demand for commercial aviation, many anticipate increased environmental impacts associated with noise, air quality, and climate change. Therefore, decision-makers and stakeholders are seeking policies, technologies, and operational procedures that balance environmental and economic interests. The main objective of this paper is to address shortcomings in current decision-making practices for aviation environmental policies. We review knowledge of the noise, air quality, and climate impacts of aviation, and demonstrate how including environmental impact assessment and quantifying uncertainties can enable a more comprehensive evaluation of aviation environmental policies. A comparison is presented between the cost-effectiveness analysis currently used for aviation environmental policy decision-making and an illustrative cost-benefit analysis. We focus on assessing a subset of the engine NO X emissions certification stringency options considered at the eighth meeting of the International Civil Aviation Organization’s Committee on Aviation Environmental Protection. The FAA Aviation environmental Portfolio Management Tool (APMT) is employed to conduct the policy assessments. We show that different conclusions may be drawn about the same policy options depending on whether benefits and interdependencies are estimated in terms of health and welfare impacts versus changes in NO X emissions inventories as is the typical practice. We also show that these conclusions are sensitive to a variety of modeling uncertainties. While our more comprehensive analysis makes the best policy option less clear, it represents a more accurate characterization of the scientific and economic uncertainties underlying impacts and the policy choices.

  10. 75 FR 22439 - Advance Notice of Proposed Rulemaking on Lead Emissions From Piston-Engine Aircraft Using Leaded...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-04-28

    ...EPA is issuing this Advance Notice of Proposed Rulemaking (ANPR) to describe information currently available and information being collected that will be used by the Administrator to issue a subsequent proposal regarding whether, in the Administrator's judgment, aircraft lead emissions from aircraft using leaded aviation gasoline (avgas) cause or contribute to air pollution which may......

  11. In-flight measurements of cruise altitude nitric oxide emission indices of commercial jet aircraft

    NASA Astrophysics Data System (ADS)

    Schulte, P.; Schlager, H.

    Simultaneous in-situ NO and CO2 measurements on board the DLR Falcon research aircraft in the exhaust plumes of commercial short to medium range jet aircraft are used to determine lower limits for the NOx emission indices EI(NOx) for cruising conditions. Concentration enhancements for NO and CO2 of 9 to 33 ppbv and 4 to 14 ppmv, respectively, relative to ambient background concentrations were observed in the exhaust trails 40 s to 130 s after emission. The derived EI(NOx)-limits range between 6.4 to 11.7 g/kg. Though the NO2 fraction in the exhaust plumes has not been measured during these pilot investigations, arguments are given that the derived lower limits represent a close approximation to the EI(NOx) values. Within the present uncertainties they are in agreement with predictions based on ground-based engine test data.

  12. Aircraft

    DTIC Science & Technology

    2003-01-01

    national power. But with the recent events such as the war with Iraq, the Severe Acute Respiratory Syndrome (SARS) outbreak, some major carriers... TITLE AND SUBTITLE 2003 Industry Studies: Aircraft 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S) 5d. PROJECT NUMBER

  13. Field Tests of a Laser Raman Measurement System for Aircraft Engine Exhaust Emissions

    DTIC Science & Technology

    1974-10-01

    practical one. The advantages of optical exhaust gas measurements versus probing systems has been demonstrated. It now remains to solve the remaining...Raman system NOVA digital data processor has the capability to service such additional measurements. If velocity information is desired a study should be...AD/A-003 648 FIELD TESTS OF A LASER RAMAN MEASURE- MENT SYSTEM FOR AIRCRAFT ENGINE EXHAUST EMISSIONS Donald A. Leunard Avoo Everett Researoh

  14. Reduction of aircraft gas turbine engine pollutant emissions

    NASA Technical Reports Server (NTRS)

    Diehl, L. A.

    1978-01-01

    To accomplish simultaneous reduction of unburned hydrocarbons, carbon monoxide, and oxides of nitrogen, required major modifications to the combustor. The modification most commonly used was a staged combustion technique. While these designs are more complicated than production combustors, no insurmountable operational difficulties were encountered in either high pressure rig or engine tests which could not be resolved with additional normal development. The emission reduction results indicate that reductions in unburned hydrocarbons were sufficient to satisfy both near and far-termed EPA requirements. Although substantial reductions were observed, the success in achieving the CO and NOx standards was mixed and depended heavily on the engine/engine cycle on which it was employed. Technology for near term CO reduction was satisfactory or marginally satisfactory. Considerable doubt exists if this technology will satisfy all far-term requirements.

  15. Aircraft emissions characterization: TF41-a2, TF30-p103, and TF30-p109 engines. Final report, December 1985-March 1987

    SciTech Connect

    Spicer, C.W.; Holdren, M.W.; Miller, S.E.; Smith, D.L.; Smith, R.N.

    1987-12-01

    Assessment of the environmental impact of aircraft operations is required by Air Force regulations. This program was undertaken with the aim of quantifying the gaseous and particulate emissions associated with three Air Force turbine engines. These engines were TF41-A2, TF30-P103, and TF30-P109. The emissions tests were carried out, using a test cell Tinker AFP, Oklahoma City, OK. All tests employed JP-4 as the fuel, and fuel samples were characterized by standard tests and analyzed for composition. Emissions were measured at power settings of idle, 30%, 75%, 100%, and afterburner (where appropriate). Measurements were made of detailed organic composition, CO, CO/sub 2/, NO, NOx, smoke number, particle concentration, and particle-size distribution. A multiport sampling rake was used to sample the exhaust, and heated Teflon tubing was used to transfer exhaust to the monitoring instrumentation. Measured and calculated fuel/air ratios were compared to assure representative sampling of the exhaust.

  16. Ultraviolet scattering properties of alumina particle clusters at three phase states in aircraft plume

    NASA Astrophysics Data System (ADS)

    Li, Jingying; Bai, Lu; Wu, Zhensen; Guo, Lixin; Gong, Yanjun

    2017-04-01

    We simulate the clusters of alumina particles using the parallel diffusion limited aggregation algorithm (DLA), and solve the scattering matrixes of the alumina particles in different phase states (alpha phase, gamma phase and liquid) through the multiple sphere T matrix method in UV. The effect of the number of monomers, fractal dimension and incident wavelength to the scattering phase function of the clusters of alumina particles is discussed. The results show that the different of the number of monomers, fractal dimensions and incident wavelengths have significant effect on the scattering properties of the clustered alumina particle. The researchers used to make the alumina particle equivalent to the alpha phase spherical particle, but it is too simplistic. We compare the scattering phase functions of the equivalent volume sphere (EVS), the equivalent surface sphere (ESS) and the clusters of alumina particles in three kinds of phase states. The results show that the backward scattering would be overestimated if the alumina particle is equivalent to the alpha phase spherical particle. Accurate phase function calculation in different phase states is very helpful to study the radiation propagation characteristics of aircraft plume.

  17. Accurate Measurements of Aircraft Engine Soot Emissions Using a CAPS PMssa Monitor

    NASA Astrophysics Data System (ADS)

    Onasch, Timothy; Thompson, Kevin; Renbaum-Wolff, Lindsay; Smallwood, Greg; Make-Lye, Richard; Freedman, Andrew

    2016-04-01

    We present results of aircraft engine soot emissions measurements during the VARIAnT2 campaign using CAPS PMssa monitors. VARIAnT2, an aircraft engine non-volatile particulate matter (nvPM) emissions field campaign, was focused on understanding the variability in nvPM mass measurements using different measurement techniques and accounting for possible nvPM sampling system losses. The CAPS PMssa monitor accurately measures both the optical extinction and scattering (and thus single scattering albedo and absorption) of an extracted sample using the same sample volume for both measurements with a time resolution of 1 second and sensitivity of better than 1 Mm-1. Absorption is obtained by subtracting the scattering signal from the total extinction. Given that the single scattering albedo of the particulates emitted from the aircraft engine measured at both 630 and 660 nm was on the order of 0.1, any inaccuracy in the scattering measurement has little impact on the accuracy of the ddetermined absorption coefficient. The absorption is converted into nvPM mass using a documented Mass Absorption Coefficient (MAC). Results of soot emission indices (mass soot emitted per mass of fuel consumed) for a turbojet engine as a function of engine power will be presented and compared to results obtained using an EC/OC monitor.

  18. Extractive sampling and optical remote sensing of F100 aircraft engine emissions.

    PubMed

    Cowen, Kenneth; Goodwin, Bradley; Joseph, Darrell; Tefend, Matthew; Satola, Jan; Kagann, Robert; Hashmonay, Ram; Spicer, Chester; Holdren, Michael; Mayfield, Howard

    2009-05-01

    The Strategic Environmental Research and Development Program (SERDP) has initiated several programs to develop and evaluate techniques to characterize emissions from military aircraft to meet increasingly stringent regulatory requirements. This paper describes the results of a recent field study using extractive and optical remote sensing (ORS) techniques to measure emissions from six F-15 fighter aircraft. Testing was performed between November 14 and 16, 2006 on the trim-pad facility at Tyndall Air Force Base in Panama City, FL. Measurements were made on eight different F100 engines, and the engines were tested on-wing of in-use aircraft. A total of 39 test runs were performed at engine power levels that ranged from idle to military power. The approach adopted for these tests involved extractive sampling with collocated ORS measurements at a distance of approximately 20-25 nozzle diameters downstream of the engine exit plane. The emission indices calculated for carbon dioxide, carbon monoxide, nitric oxide, and several volatile organic compounds showed very good agreement when comparing the extractive and ORS sampling methods.

  19. Methodology to estimate particulate matter emissions from certified commercial aircraft engines.

    PubMed

    Wayson, Roger L; Fleming, Gregg G; Lovinelli, Ralph

    2009-01-01

    Today, about one-fourth of U.S. commercial service airports, including 41 of the busiest 50, are either in nonattainment or maintenance areas per the National Ambient Air Quality Standards. U.S. aviation activity is forecasted to triple by 2025, while at the same time, the U.S. Environmental Protection Agency (EPA) is evaluating stricter particulate matter (PM) standards on the basis of documented human health and welfare impacts. Stricter federal standards are expected to impede capacity and limit aviation growth if regulatory mandated emission reductions occur as for other non-aviation sources (i.e., automobiles, power plants, etc.). In addition, strong interest exists as to the role aviation emissions play in air quality and climate change issues. These reasons underpin the need to quantify and understand PM emissions from certified commercial aircraft engines, which has led to the need for a methodology to predict these emissions. Standardized sampling techniques to measure volatile and nonvolatile PM emissions from aircraft engines do not exist. As such, a first-order approximation (FOA) was derived to fill this need based on available information. FOA1.0 only allowed prediction of nonvolatile PM. FOA2.0 was a change to include volatile PM emissions on the basis of the ratio of nonvolatile to volatile emissions. Recent collaborative efforts by industry (manufacturers and airlines), research establishments, and regulators have begun to provide further insight into the estimation of the PM emissions. The resultant PM measurement datasets are being analyzed to refine sampling techniques and progress towards standardized PM measurements. These preliminary measurement datasets also support the continued refinement of the FOA methodology. FOA3.0 disaggregated the prediction techniques to allow for independent prediction of nonvolatile and volatile emissions on a more theoretical basis. The Committee for Aviation Environmental Protection of the International Civil

  20. Laser plasma emission of small particles in different gas atmospheres

    NASA Astrophysics Data System (ADS)

    Andreev, Alexander A.; Ueda, Toshitsugu; Wakamatsu, Muneaki

    2002-06-01

    The problem of laser pulse interaction with small solid particles in a gas atmosphere when detecting its parameters is a serous one in industrial and environmental applications. Previous investigations have shown the possibility of using the laser induced breakdown method. This method is very sensitive, but for a particle size of less than 0.1 micrometers the damage threshold of the solid target is very close to the breakdown point of pure gas. At breakdown, a small volume of dense hot plasma emits radiation by which the size and material of particles can be detected. We used an analytical model, simulation code and experiments to analyze this radiation and found that the emitted intensity varied with laser, gas and particle parameters. The increased dependence of SSP plasma emission rate on initial particle volume permits this method to be used for measuring small particle size by using emitted line spectrum at the late time stage.

  1. Effective Radius of Ice Cloud Particle Populations Derived from Aircraft Probes

    NASA Technical Reports Server (NTRS)

    Heymsfield, Andrew J.; Schmitt, Carl; Bansemer, Aaron; vanZadelhoff, Gerd-Jan; McGill, Matthew J.; Twohy, Cynthia

    2005-01-01

    The effective radius(r(sub e)) is a crucial variable in representing the radiative properties of cloud layers in general circulation models. This parameter is proportional to the condensed water content (CWC) divided by the extinction (sigma). For ice cloud layers, parameterizations for r(sub e), have been developed from aircraft in-situ measurements 1) indirectly, using data obtained from particle spectrometer probes and assumptions or observations about particle shape and mass to get the ice water content (IWC) and area to get sigma, and recently 2) from probes that measure IWC and sigma directly. This study compares [IWC/sigma] derived from the two methods using data sets acquired from comparable instruments on two aircraft, one sampling clouds at mid-levels and the other at upper-levels during the CRYSTAL-FACE field program in Florida in 2002. The sigma and IWC derived by each method are compared and evaluated in different ways for each aircraft data set. Direct measurements of sigma exceed those derived indirectly by a factor of two to two and a half. The IWC probes, relying on ice sublimation, appear to measure accurately except when the IWC is high or the particles too large to sublimate completely during the short transit time through the probe. The IWC estimated from the particle probes are accurate when direct measurements are available to provide constraints and useful information in high IWC/large particle situations. Because of the discrepancy in sigma estimates between the direct and indirect approaches, there is a factor of 2 to 3 difference in [IWC/sigma] between them. Although there are significant uncertainties involved in its use, comparisons with several independent data sources suggest that the indirect method is the more accurate of the two approaches. However, experiments are needed to resolve the source of the discrepancy in sigma.

  2. Sampling and analysis of aircraft engine cold start particles and demonstration of an electrostatic personal particle sampler.

    PubMed

    Armendariz, Alfredo; Leith, David; Boundy, Maryanne; Goodman, Randall; Smith, Les; Carlton, Gary

    2003-01-01

    Aircraft engines emit an aerosol plume during startup in extremely cold weather that can drift into areas occupied by flightline ground crews. This study tested a personal sampler used to assess exposure to particles in the plume under challenging field conditions. Area and personal samples were taken at two U.S. Air Force (USAF) flightlines during the winter months. Small tube-and-wire electrostatic precipitators (ESPs) were mounted on a stationary stand positioned behind the engines to sample the exhaust. Other ESPs were worn by ground crews to sample breathing zone concentrations. In addition, an aerodynamic particle sizer 3320 (APS) was used to determine the size distribution of the particles. Samples collected with the ESP were solvent extracted and analyzed with gas chromatography-mass spectrometry. Results indicated that the plume consisted of up to 75 mg/m(3) of unburned jet fuel particles. The APS showed that nearly the entire particle mass was respirable, because the plumes had mass median diameters less than 2 micro m. These tests demonstrated that the ESP could be used at cold USAF flightlines to perform exposure assessments to the cold start particles.

  3. Ground-based aircraft exhaust measurements of a Lufthansa Airbus A340 using FTIR emission spectrometry

    NASA Astrophysics Data System (ADS)

    Schaefer, Klaus; Heland, Joerg

    1999-01-01

    The emission inventories of aircraft emissions are being set up using flight routing data and test rig measurements of the engine manufacturers for certification purposes which have to be extrapolated with respect to the actual parameters at cruise altitude. Precise data from in-service engines are not existing. FTIR-emission-spectroscopy as a remote sensing multi-component exhaust gas analysis method has been further developed to specify the traceable molecules in aircraft exhausts, to determine the detection limits, and to obtain reliable statements concerning its accuracy. The first measurement with the Airbus A340 engine CFM56-5C2 during run up tests at ground level showed the overall ability of the FTIR-emission system to analyze the exhausts of modern gas turbines with high bypass ratio and mixing of fan air into the exhausts before the nozzle exit. Good quality spectra were measured and analyzed with respect to the mixing rations of CO2, H2O, CO, NO, and N2O, and the emission indices of CO, NO, and N2O. Total measurement times at one thrust level should be about 15 minutes to obtain reliable result which can be compared to the ICAO data of this engine.

  4. Asian emissions of CO and NOx: Constraints from aircraft and Chinese station data

    NASA Astrophysics Data System (ADS)

    Wang, Yuxuan X.; McElroy, Michael B.; Wang, Tao; Palmer, Paul I.

    2004-12-01

    Observations of CO and NOy from the Transport and Chemical Evolution over the Pacific (TRACE-P) aircraft mission over the northwest Pacific and from two Chinese ground stations (Hong Kong and Lin An) during spring 2001 are used in conjunction with an optimal estimation inverse model to constrain estimates of Asian emissions of CO and NOx. A priori emissions are based on a detailed bottom-up inventory for the observation period. The inversion analysis requires 43% and 47% increases in Chinese emissions of CO and NOx, respectively, distributed heterogeneously, with the largest adjustments required for central China. A posteriori estimates of emissions from biomass burning in Southeast Asia are much lower than a priori values. Inversion results for NOx emissions are consistent with CO emissions in terms of the sense of the adjustments. Inclusion of the station data in the inversion analysis significantly improves estimates for emissions from central and south China. A large increase in NOx emissions inferred for central China (a factor of 3) is attributed to decomposition of organic wastes associated with the human-animal food chain and extensive applications of chemical fertilizer. An analysis of emission ratios for CO relative to NOx for different sectors indicates that emissions attributed to industry and transportation may be underestimated in the bottom-up inventory for central China, while emissions from the domestic sector may be underestimated for south China. An increase in emission factors could help reconcile results from the inversion analysis with the "bottom-up" approach. Detailed analysis of the surface observations using a posteriori emissions indicates the importance of meteorological phenomena, notably cold fronts in March and small-scale high- and low-pressure systems in April in modulating concentrations of CO, with the latter most evident in the data from Lin An.

  5. Experimental studies on particle emissions from cruising ship, their characteristic properties, transformation and atmospheric lifetime in the marine boundary layer

    NASA Astrophysics Data System (ADS)

    Petzold, A.; Hasselbach, J.; Lauer, P.; Baumann, R.; Franke, K.; Gurk, C.; Schlager, H.; Weingartner, E.

    2007-10-01

    Particle emissions from ship engines and their atmospheric transformation in the marine boundary layer (MBL) were investigated in engine test bed studies and in airborne measurements of expanding ship plumes. During the test rig studies, detailed aerosol microphysical and chemical properties were measured in the exhaust gas of a serial MAN B&W seven-cylinder four-stroke marine diesel engine under various load conditions. The emission studies were complemented by airborne aerosol transformation studies in the plume of a large container ship in the English Channel using the DLR aircraft Falcon 20 E-5. Observations from emission studies and plume studies combined with a Gaussian plume dispersion model yield a consistent picture of particle transformation processes from emission to atmospheric processing during plume expansion. Particulate matter emission indices obtained from plume measurements are 8.8±1.0×1015(kg fuel)-1 by number for non-volatile particles and 174±43 mg (kg fuel)-1 by mass for Black Carbon (BC). Values determined for test rig conditions between 85 and 110% engine load are of similar magnitude. For the total particle number including volatile compounds no emission index can be derived since the volatile aerosol fraction is subject to rapid transformation processes in the plume. Ship exhaust particles occur in the size range Dp<0.3 μm, showing a bi-modal structure. The combustion particle mode is centred at modal diameters of 0.05 μm for raw emissions to 0.10 μm at a plume age of 1 h. The smaller-sized volatile particle mode is centred at Dp≤0.02 μm. From the decay of ship exhaust particle number concentrations in an expanding plume, a maximum plume life time of approx. 24 h is estimated for a well-mixed marine boundary layer.

  6. Experimental studies on particle emissions from cruising ship, their characteristic properties, transformation and atmospheric lifetime in the marine boundary layer

    NASA Astrophysics Data System (ADS)

    Petzold, A.; Hasselbach, J.; Lauer, P.; Baumann, R.; Franke, K.; Gurk, C.; Schlager, H.; Weingartner, E.

    2008-05-01

    Particle emissions from ship engines and their atmospheric transformation in the marine boundary layer (MBL) were investigated in engine test bed studies and in airborne measurements of expanding ship plumes. During the test rig studies, detailed aerosol microphysical and chemical properties were measured in the exhaust gas of a serial MAN B&W seven-cylinder four-stroke marine diesel engine under various load conditions. The emission studies were complemented by airborne aerosol transformation studies in the plume of a large container ship in the English Channel using the DLR aircraft Falcon 20 E-5. Observations from emission studies and plume studies combined with a Gaussian plume dispersion model yield a consistent picture of particle transformation processes from emission to atmospheric processing during plume expansion. Particulate matter emission indices obtained from plume measurements are 8.8±1.0×1015(kg fuel)-1 by number for non-volatile particles and 174±43 mg (kg fuel)-1 by mass for Black Carbon (BC). Values determined for test rig conditions between 85 and 110% engine load are of similar magnitude. For the total particle number including volatile compounds no emission index can be derived since the volatile aerosol fraction is subject to rapid transformation processes in the plume. Ship exhaust particles occur in the size range Dp<0.3 μm, showing a bi-modal structure. The combustion particle mode is centred at modal diameters of 0.05 μm for raw emissions to 0.10 μm at a plume age of 1 h. The smaller-sized volatile particle mode is centred at Dp≤0.02 μm. From the decay of ship exhaust particle number concentrations in an expanding plume, a maximum plume life time of approx. 24 h is estimated for a well-mixed marine boundary layer.

  7. Aircraft mass budgeting to measure CO2 emissions of Rome, Italy.

    PubMed

    Gioli, Beniamino; Carfora, Maria F; Magliulo, Vincenzo; Metallo, Maria C; Poli, Attilio A; Toscano, Piero; Miglietta, Franco

    2014-04-01

    Aircraft measurements were used to estimate the CO2 emission rates of the city of Rome, assessed against high-resolution inventorial data. Three experimental flights were made, composed of vertical soundings to measure Planetary Boundary Layer (PBL) properties, and circular horizontal transects at various altitudes around the city area. City level emissions and associated uncertainties were computed by means of mass budgeting techniques, obtaining a positive net CO2 flux of 14.7 ± 4.5, 2.5 ± 1.2, and 10.3 ± 1.2 μmol m(-2) s(-1) for the three flights. Inventorial CO2 fluxes at the time of flights were computed by means of spatial and temporal disaggregation of the gross emission inventory, at 10.9 ± 2.5, 9.6 ± 1.3, and 17.4 ± 9.6 μmol m(-2) s(-1). The largest differences between the two dataset are associated with a greater variability of wind speed and direction in the boundary layer during measurements. Uncertainty partitioned into components related to horizontal boundary flows and top surface flow, revealed that the latter dominates total uncertainty in the presence of a wide variability of CO2 concentration in the free troposphere (up to 7 ppm), while it is a minor term with uniform tropospheric concentrations in the study area (within 2 ppm). Overall, we demonstrate how small aircraft may provide city level emission measurements that may integrate and validate emission inventories. Optimal atmospheric conditions and measurement strategies for the deployment of aircraft experimental flights are finally discussed.

  8. Modeling emissivity of low-emissivity coating containing horizontally oriented metallic flake particles

    NASA Astrophysics Data System (ADS)

    Chen, Shuai; Yuan, Le; Weng, Xiaolong; Deng, Longjiang

    2014-11-01

    The scattering and absorption cross sections of horizontally oriented metallic flake particles are estimated by extended geometric optics that includes diffraction and edge effects. Emissivity of the coating containing those particles is calculated using Kubelka-Munk theory. The dependence of emissivity of the coating on the radius, thickness, content of metallic flake particles and coating thickness is discussed. Finally, theoretical results are compared with the experimental measurements with Al/acrylic resin coating system and the results show that simulation values are in good agreement with experimental ones.

  9. Application of supersonic particle deposition to enhance the structural integrity of aircraft structures

    NASA Astrophysics Data System (ADS)

    Matthews, N.; Jones, R.; Sih, G. C.

    2014-01-01

    Aircraft metal components and structures are susceptible to environmental degradation throughout their original design life and in many cases their extended lives. This paper summarizes the results of an experimental program to evaluate the ability of Supersonic Particle Deposition (SPD), also known as cold spray, to extend the limit of validity (LOV) of aircraft structural components and to restore the structural integrity of corroded panels. In this study [LU1]the potential for the SPD to seal the mechanically fastened joints and for this seal to remain intact even in the presence of multi-site damage (MSD) has been evaluated. By sealing the joint the onset of corrosion damage in the joint can be significantly retarded, possibly even eliminated, thereby dramatically extending the LOV of mechanically fastened joints. The study also shows that SPD can dramatically increase the damage tolerance of badly corroded wing skins.

  10. Aircraft emissions of methane and nitrous oxide during the alternative aviation fuel experiment.

    PubMed

    Santoni, Gregory W; Lee, Ben H; Wood, Ezra C; Herndon, Scott C; Miake-Lye, Richard C; Wofsy, Steven C; McManus, J Barry; Nelson, David D; Zahniser, Mark S

    2011-08-15

    Given the predicted growth of aviation and the recent developments of alternative aviation fuels, quantifying methane (CH(4)) and nitrous oxide (N(2)O) emission ratios for various aircraft engines and fuels can help constrain projected impacts of aviation on the Earth's radiative balance. Fuel-based emission indices for CH(4) and N(2)O were quantified from CFM56-2C1 engines aboard the NASA DC-8 aircraft during the first Alternative Aviation Fuel Experiment (AAFEX-I) in 2009. The measurements of JP-8 fuel combustion products indicate that at low thrust engine states (idle and taxi, or 4% and 7% maximum rated thrusts, respectively) the engines emit both CH(4) and N(2)O at a mean ± 1σ rate of 170 ± 160 mg CH(4) (kg Fuel)(-1) and 110 ± 50 mg N(2)O (kg Fuel)(-1), respectively. At higher thrust levels corresponding to greater fuel flow and higher engine temperatures, CH(4) concentrations in engine exhaust were lower than ambient concentrations. Average emission indices for JP-8 fuel combusted at engine thrusts between 30% and 100% of maximum rating were -54 ± 33 mg CH(4) (kg Fuel)(-1) and 32 ± 18 mg N(2)O (kg Fuel)(-1), where the negative sign indicates consumption of atmospheric CH(4) in the engine. Emission factors for the synthetic Fischer-Tropsch fuels were statistically indistinguishable from those for JP-8.

  11. Measurement and analysis of aircraft engine PM emissions downwind of an active runway at the Oakland International Airport

    NASA Astrophysics Data System (ADS)

    Lobo, Prem; Hagen, Donald E.; Whitefield, Philip D.

    2012-12-01

    The growth of commercial aviation has fueled concerns over air quality around airports and the surrounding communities. Airports must expand their operations to meet the increase in air traffic, but expansion plans have been delayed or canceled due to concerns over local air quality. This paper presents the methodology for real-time measurements of aircraft engine specific Particulate Matter (PM) emissions and analysis of the associated high resolution data acquired during normal Landing and Take-Off (LTO) operations 100-300 m downwind of an active taxi-/runway at the Oakland International Airport. The airframe-engine combinations studied included B737-300 with CFM56-3B engines, B737-700/800 with CFM56-7B engines, A320 with V2500-A5 engines, MD-80 with JT-8D engines, A300 with CF6-80 engines, DC-10 with CF6-50 engines, and CRJ-100/200 with CF34-3B engines. For all engine types studied, the size distributions were typically bimodal in nature with a nucleation mode comprised of freshly nucleated PM and an accumulation mode comprised mostly of PM soot with some condensed volatile material. The PM number-based emission index observed ranged between 7 × 1015-3 × 1017 particles kg-1 fuel burned at idle/taxi and between 4 × 1015-2 × 1017 particles kg-1 fuel burned at take-off, and the associated PM mass-based emission index (EIm) ranged between 0.1 and 0.7 g kg-1 fuel burned at both the idle/taxi and take-off conditions. Older technology engines such as the CFM56-3B and JT8D engines were observed to have as much as 3× higher PM EIm values at take-off compared to newer engine technology such as the CFM56-7B engine. The results from this study provide information for better characterizing evolving PM emissions from in-service commercial aircraft under normal LTO operations and assessing their impact on local and regional air quality and health related impacts.

  12. Particle number concentrations over Europe in 2030: the role of emissions and new particle formation

    NASA Astrophysics Data System (ADS)

    Ahlm, L.; Julin, J.; Fountoukis, C.; Pandis, S. N.; Riipinen, I.

    2013-04-01

    The aerosol particle number concentration is a key parameter when estimating impacts of aerosol particles on climate and human health. We use a three-dimensional chemical transport model with detailed microphysics, PMCAMx-UF, to simulate particle number concentrations over Europe in the year 2030, by applying emission scenarios for trace gases and primary aerosols. The scenarios are based on expected changes in anthropogenic emissions of sulphur dioxide, ammonia, nitrogen oxides, and primary aerosol particles with a diameter less than 2.5 μm (PM2.5) focusing on a photochemically active period. For the baseline scenario, which represents a best estimate of the evolution of anthropogenic emissions in Europe, PMCAMx-UF predicts that the total particle number concentration (Ntot) will decrease by 30-70% between 2008 and 2030. The number concentration of particles larger than 100 nm (N100), a proxy for cloud condensation nuclei (CCN) concentration, is predicted to decrease by 40-70% during the same period. The predicted decrease in Ntot is mainly a result of reduced new particle formation due to the expected reduction in SO2 emissions, whereas the predicted decrease in N100 is a result of both decreasing condensational growth and reduced primary aerosol emissions. For larger emission reductions, PMCAMx-UF predicts reductions of 60-80% in both Ntot and N100 over Europe. Sensitivity tests reveal that a reduction in SO2 emissions is far more efficient than any other emission reduction investigated, in reducing Ntot. For N100, emission reductions of both SO2 and PM2.5 contribute significantly to the reduced concentration, even though SO2 plays the dominant role once more. The impact of SO2 for both new particle formation and growth over Europe may be expected to be somewhat higher during the simulated period with high photochemical activity than during times of the year with less incoming solar radiation. The predicted reductions in both Ntot and N100 between 2008 and 2030

  13. Particle number concentrations over Europe in 2030: the role of emissions and new particle formation

    NASA Astrophysics Data System (ADS)

    Ahlm, L.; Julin, J.; Fountoukis, C.; Pandis, S. N.; Riipinen, I.

    2013-10-01

    The aerosol particle number concentration is a key parameter when estimating impacts of aerosol particles on climate and human health. We use a three-dimensional chemical transport model with detailed microphysics, PMCAMx-UF, to simulate particle number concentrations over Europe in the year 2030, by applying emission scenarios for trace gases and primary aerosols. The scenarios are based on expected changes in anthropogenic emissions of sulfur dioxide, ammonia, nitrogen oxides, and primary aerosol particles with a diameter less than 2.5 μm (PM2.5) focusing on a photochemically active period, and the implications for other seasons are discussed. For the baseline scenario, which represents a best estimate of the evolution of anthropogenic emissions in Europe, PMCAMx-UF predicts that the total particle number concentration (Ntot) will decrease by 30-70% between 2008 and 2030. The number concentration of particles larger than 100 nm (N100), a proxy for cloud condensation nuclei (CCN) concentration, is predicted to decrease by 40-70% during the same period. The predicted decrease in Ntot is mainly a result of reduced new particle formation due to the expected reduction in SO2 emissions, whereas the predicted decrease in N100 is a result of both decreasing condensational growth and reduced primary aerosol emissions. For larger emission reductions, PMCAMx-UF predicts reductions of 60-80% in both Ntot and N100 over Europe. Sensitivity tests reveal that a reduction in SO2 emissions is far more efficient than any other emission reduction investigated, in reducing Ntot. For N100, emission reductions of both SO2 and PM2.5 contribute significantly to the reduced concentration, even though SO2 plays the dominant role once more. The impact of SO2 for both new particle formation and growth over Europe may be expected to be somewhat higher during the simulated period with high photochemical activity than during times of the year with less incoming solar radiation. The predicted

  14. Fracto-emission - The role of charge separation. [in particle emission during fracture

    NASA Technical Reports Server (NTRS)

    Dickinson, J. T.; Jensen, L. C.; Jahan-Latibari, A.

    1984-01-01

    Fracto-emission is the emission of particles (e.g., electrons, ions, ground state and excited neutrals, and photons) during and following fracture. It is found that during fracture in vacuum of adhesive bonds and crystalline materials involving large amounts of charge separation on the surface the emission of charged particles, excited neutrals, light, and radio waves occurs with unique and revealing time dependencies. Simultaneous fracto-emission measurements on several systems are reported. The results are interpreted in terms of a conceptual model involving the following steps: (1) charge separation due to fracture, (2) desorption of gases from the material into the crack tip, (3) a gas discharge in the crack, (4) energetic bombardment of the freshly created crack walls, and (5) thermally stimulated electron emission, accompanied by electron stimulated desorption of ions and excited neutrals. In addition to evidence from fracture experiments, results from studies of electron bombardment of a polymer surface are presented.

  15. Capabilities Enhanced for Researching the Reduction of Emissions in Future Aircraft

    NASA Technical Reports Server (NTRS)

    1995-01-01

    Aircraft future aircraft jet engines will run at higher pressures to obtain greater fuel efficiency and performance. This will require new combustor designs to keep the nitrogen oxide and carbon monoxide emissions at environmentally acceptable levels. The actual pressures and temperatures found in gas turbine combustors must be duplicated in a laboratory to verify the emissions characteristics of gas turbine engines. Recognizing this, the U.S. aircraft gas turbine industry identified a need for a national facility that could duplicate the severe inlet conditions of future combustors. Because of our expertise in combustion emissions reduction research and in the design and operation of high-pressure test facilities, the NASA Lewis Research Center was seen as the natural location for such a facility. As a national laboratory, Lewis could provide these facilities to all U.S. gas turbine engine manufacturers while protecting their proprietary interests. Called the Advanced Subsonic Combustion Rig, the facility will provide up to 60-atm pressures at inlet temperatures up to 1300 F and air flow rates up to 38 lb/sec. Furthermore, it will offer state-of-the-art diagnostic methods for characterizing advanced combustor concepts. Aeronautical combustion research at Lewis provided several significant accomplishments recently in support of both the High Speed Research (HSR) and Advanced Subsonic Technology (AST) programs. For example, in the High Speed Research Program, NO_x reductions of up to 90 percent were achieved in prototype combustor hardware. Advanced computational analysis, gas sampling, and laser diagnostic techniques were critical to this success. Working closely with the gas turbine industry, we have successfully transferred this low-emissions combustor technology into engine prototype hardware. This hardware is now being tested at the engine manufacturers facilities. Complementary tests in Lewis currently available 30-atm test facilities are also underway, taking

  16. Particle emissions from ships: dependence on fuel type.

    PubMed

    Winnes, Hulda; Fridell, Erik

    2009-12-01

    This paper presents the results of field emission measurements that have been carried out on the 4500-kW four-stroke main engine on-board a product tanker. Two fuel qualities--heavy fuel oil (HFO) and marine gas oil (MGO)-have been tested on the same engine for comparable load settings. A fuel switch within the marine sector is approaching and the aim of this study is to draw initial conclusions on the subsequent effects on ship exhaust gas composition and emission factors with a focus on particles. Measurements on exhaust gas concentrations of carbon dioxide (CO2), carbon monoxide (CO), nitrogen oxides (NOx), sulfur dioxide (SO2), total hydrocarbons (HCs), and particulate matter (PM) were conducted. The gases, except SO2, did not show any major differences between the fuels. Specific PM emissions were generally higher for HFO than for MGO; however, for the smallest size-fraction measured containing particles 0.30-0.40 microm in diameter, the opposite is observed. This finding emphasizes that to minimize negative health effects of particles from ships, further regulation may be needed to reduce small-sized particles; a fuel shift to low sulfur fuel alone does not seem to accomplish this reduction. The average of this and previously published data from on-board studies on particle emissions from ships results in emissions factors of 0.33 and 1.34 g/kWh for marine distillate oil (MDO) and HFO, respectively. Accounting for 1 standard deviation in each direction from the average values gives a range of 0.18-0.48 g/kWh for MDO and 0.56-2.12 g/kWh for HFO.

  17. Characterization of multiphoton emission from aggregated gold nano particles

    NASA Astrophysics Data System (ADS)

    Eguchi, Akira; Lu, Phat; Kim, Youngsik; Milster, Tom D.

    2016-09-01

    Although gold nanoparticles (GNPs) are promising probes for biological imaging because of their attracting optical properties and bio-friendly nature, properties of the multi-photon (MP) emission from GNP aggregates produced by a short-wave infrared (SWIR) laser have not been examined. In this paper, characterization of MP emission from aggregated 50 nm GNPs excited by a femtosecond (fs) laser at 1560 nm is discussed with respect to aggregate structures. The key technique in this work is single particle spectroscopy. A pattern matching technique is applied to correlate MP emission and SEM images, which includes an optimization processes to maximize cross correlation coefficients between a binary microscope image and a binary SEM image with respect to xy displacement, image rotation angle, and image magnification. Once optimization is completed, emission spots are matched to the SEM image, which clarifies GNP ordering and emission properties of each aggregate. Correlation results showed that GNP aggregates have stronger MP emission than single GNPs. By combining the pattern matching technique with spectroscopy, MP emission spectrum is characterized for each GNP aggregate. A broad spectrum in the visible region and near infrared (NIR) region is obtained from GNP dimers, unlike previously reported surface plasmon enhanced emission spectrum.

  18. Fine and ultrafine particle emissions from microwave popcorn.

    PubMed

    Zhang, Q; Avalos, J; Zhu, Y

    2014-04-01

    This study characterized fine (PM2.5 ) and ultrafine particle (UFP, diameter < 100 nm) emissions from microwave popcorn and analyzed influential factors. Each pre-packed popcorn bag was cooked in a microwave oven enclosed in a stainless steel chamber for 3 min. The number concentration and size distribution of UFPs and PM2.5 mass concentration were measured inside the chamber repeatedly for five different flavors under four increasing power settings using either the foil-lined original package or a brown paper bag. UFPs and PM2.5 generated by microwaving popcorn were 150-560 and 350-800 times higher than the emissions from microwaving water, respectively. About 90% of the total particles emitted were in the ultrafine size range. The emitted PM concentrations varied significantly with flavor. Replacing the foil-lined original package with a brown paper bag significantly reduced the peak concentration by 24-87% for total particle number and 36-70% for PM2.5 . A positive relationship was observed between both UFP number and PM2.5 mass and power setting. The emission rates of microwave popcorn ranged from 1.9 × 10(10) to 8.0 × 10(10) No./min for total particle number and from 134 to 249 μg/min for PM2.5 .

  19. Impact of aircraft NOx emissions on the atmosphere - tradeoffs to reduce the impact

    NASA Astrophysics Data System (ADS)

    Gauss, M.; Isaksen, I. S. A.; Lee, D. S.; Søvde, O. A.

    2006-05-01

    Within the EU-project TRADEOFF, the impact of NOx (=NO+NO2) emissions from subsonic aviation upon the chemical composition of the atmosphere has been calculated with focus on changes in reactive nitrogen and ozone. We apply a 3-D chemical transport model that includes comprehensive chemistry for both the troposphere and the stratosphere and uses various aircraft emission scenarios developed during TRADEOFF for the year 2000. The environmental effects of enhanced air traffic along polar routes and of possible changes in cruising altitude are investigated, taking into account effects of flight route changes on fuel consumption and emissions.

    In a reference case including both civil and military aircraft the model predicts aircraft-induced maximum increases of zonal-mean NOy (=total reactive nitrogen) between 156 pptv (August) and 322 pptv (May) in the tropopause region of the Northern Hemisphere. Resulting maximum increases in zonal-mean ozone vary between 3.1 ppbv in September and 7.7 ppbv in June.

    Enhanced use of polar routes implies substantially larger zonal-mean ozone increases in high Northern latitudes during summer, while the effect is negligible in winter.

    Lowering the flight altitude leads to smaller ozone increases in the lower stratosphere and upper troposphere, and to larger ozone increases at altitudes below. Regarding total ozone change, the degree of cancellation between these two effects depends on latitude and season, but annually and globally averaged the contribution from higher altitudes dominates, mainly due to washout of NOy in the troposphere, which weakens the tropospheric increase.

    Raising flight altitudes increases the ozone burden both in the troposphere and the lower stratosphere, primarily due to a more efficient accumulation of pollutants in the stratosphere.

  20. AN ENGINE EXHAUST PARTICLE SIZERTM SPECTROMETER FOR TRANSIENT EMISSION PARTICLE MEASUREMENTS

    SciTech Connect

    Johnson, T; Caldow, R; Pucher, A; Mirme, A; Kittelson, D

    2003-08-24

    There has been increased interest in obtaining size distribution data during transient engine operation where both particle size and total number concentrations can change dramatically. Traditionally, the measurement of particle emissions from vehicles has been a compromise based on choosing between the conflicting needs of high time resolution or high particle size resolution for a particular measurement. Currently the most common technique for measuring submicrometer particle sizes is the Scanning Mobility Particle Sizer (SMPSTM) system. The SMPS system gives high size resolution but requires an aerosol to be stable over a long time period to make a particle size distribution measurement. A Condensation Particle Counter (CPC) is commonly used for fast time response measurements but is limited to measuring total concentration only. This paper describes a new instrument, the Engine Exhaust Particle SizerTM (EEPSTM) spectrometer, which has high time resolution and a reasonable size resolution. The EEPS was designed specifically for measuring engine exhaust and, like the SMPS system, uses a measurement based on electrical mobility. Particles entering the instrument are charged to a predictable level, then passed through an annular space where they are repelled outward by the voltage from a central column. When the particles reach electrodes on the outer cylindrical (a column of rings), they create a current that is measured by an electrometer on one or more of the rings. The electrometer currents are measured multiple times per second to give high time resolution. A sophisticated realtime inversion algorithm converts the currents to particle size and concentration for immediate display.

  1. AN ENGINE EXHAUST PARTICLE SIZER{trademark} SPECTROMETER FOR TRANSIENT EMISSION PARTICLE MEASUREMENTS

    SciTech Connect

    Johnson, T: Caldow, R; Pucher, A Mirme, A Kittelson, D

    2003-08-24

    There has been increased interest in obtaining size distribution data during transient engine operation where both particle size and total number concentrations can change dramatically. Traditionally, the measurement of particle emissions from vehicles has been a compromise based on choosing between the conflicting needs of high time resolution or high particle size resolution for a particular measurement. Currently the most common technique for measuring submicrometer particle sizes is the Scanning Mobility Particle Sizer (SMPSTM) system. The SMPS system gives high size resolution but requires an aerosol to be stable over a long time period to make a particle size distribution measurement. A Condensation Particle Counter (CPC) is commonly used for fast time response measurements but is limited to measuring total concentration only. This paper describes a new instrument, the Engine Exhaust Particle SizerTM (EEPSTM) spectrometer, which has high time resolution and a reasonable size resolution. The EEPS was designed specifically for measuring engine exhaust and, like the SMPS system, uses a measurement based on electrical mobility. Particles entering the instrument are charged to a predictable level, then passed through an annular space where they are repelled outward by the voltage from a central column. When the particles reach electrodes on the outer cylindrical (a column of rings), they create a current that is measured by an electrometer on one or more of the rings. The electrometer currents are measured multiple times per second to give high time resolution. A sophisticated realtime inversion algorithm converts the currents to particle size and concentration for immediate display.

  2. Impacts of aircraft emissions on the air quality near the ground

    NASA Astrophysics Data System (ADS)

    Lee, H.; Olsen, S. C.; Wuebbles, D. J.; Youn, D.

    2013-01-01

    The continuing increase in demand for commercial aviation transport raises questions about the effects of resulting emissions on the environment. The purpose of this study is to investigate, using a global chemistry transport model, to what extent aviation emissions outside the boundary layer influence air quality in the boundary layer. The effects of current levels of aircraft emissions were studied through comparison of multiple simulations allowing for the separated effects of aviation emissions occurring in the low, middle and upper troposphere. We show that emissions near cruise altitudes rather than emissions during landing and take-off are responsible for most of the total odd-nitrogen (NOy), ozone (O3) and aerosol perturbations near the ground with a noticeable seasonal difference. Overall, the perturbations of these species are smaller than 1 ppb even in winter when the perturbations are greater than in summer. Based on the widely used air quality standards and uncertainty of state-of-the-art models, we conclude that aviation-induced perturbations have a negligible effect on air quality even in areas with heavy air traffic. Aviation emissions lead to a less than 1% aerosol enhancement in the boundary layer due to a slight increase in ammonium nitrate (NH4NO3) during cold seasons and a statistically insignificant aerosol perturbation in summer. In addition, statistical analysis using probability density functions, Hellinger distance, and p-value indicate that aviation emissions outside the boundary layer do not affect the occurrence of extremely high aerosol concentrations in the boundary layer. An additional sensitivity simulation assuming the doubling of surface ammonia emissions demonstrates that the aviation induced aerosol increase near the ground is highly dependent on background ammonia concentrations whose current range of uncertainty is large.

  3. Impacts of aircraft emissions on the air quality near the ground

    NASA Astrophysics Data System (ADS)

    Lee, H.; Olsen, S. C.; Wuebbles, D. J.; Youn, D.

    2013-06-01

    The continuing increase in demand for commercial aviation transport raises questions about the effects of resulting emissions on the environment. The purpose of this study is to investigate, using a global chemistry transport model, to what extent aviation emissions outside the boundary layer influence air quality in the boundary layer. The large-scale effects of current levels of aircraft emissions were studied through comparison of multiple simulations allowing for the separated effects of aviation emissions occurring in the low, middle and upper troposphere. We show that emissions near cruise altitudes (9-11 km in altitude) rather than emissions during landing and take-off are responsible for most of the total odd-nitrogen (NOy), ozone (O3) and aerosol perturbations near the ground with a noticeable seasonal difference. Overall, the perturbations of these species are smaller than 1 ppb even in winter when the perturbations are greater than in summer. Based on the widely used air quality standards and uncertainty of state-of-the-art models, we conclude that aviation-induced perturbations have a negligible effect on air quality even in areas with heavy air traffic. Aviation emissions lead to a less than 1% aerosol enhancement in the boundary layer due to a slight increase in ammonium nitrate (NH4NO3) during cold seasons and a statistically insignificant aerosol perturbation in summer. In addition, statistical analysis using probability density functions, Hellinger distance, and p value indicate that aviation emissions outside the boundary layer do not affect the occurrence of extremely high aerosol concentrations in the boundary layer. An additional sensitivity simulation assuming the doubling of surface ammonia emissions demonstrates that the aviation induced aerosol increase near the ground is highly dependent on background ammonia concentrations whose current range of uncertainty is large.

  4. Radio Emission by Particles Accelerated in Pulsar Magnetosphere

    NASA Astrophysics Data System (ADS)

    Thomas, R. M. C.; Gangadhara, R. T.

    2003-03-01

    We present a relativistic model of pulsar radio emission by plasma accelerated along the rotating magnetic field lines projected on to a 2D plane perpendicular to the rotation axis. We have derived the expression for the trajectory of a particle, and estimated the spectrum of radio emission by the plasma bunches. We used the parameters given in the paper by Peyman and Gangadhara (2002). Further the analystical expressions for the Stokes parameters are derived, and compared them with the observed profiles. The one sense of circular polarization, observed in many pulsars, can be explained in the light of our model.

  5. Particle- and Gaseous Emissions from an LNG Powered Ship.

    PubMed

    Anderson, Maria; Salo, Kent; Fridell, Erik

    2015-10-20

    Measurements of particle number and mass concentrations and number size distribution of particles from a ship running on liquefied natural gas (LNG) were made on-board a ship with dual-fuel engines installed. Today there is a large interest in LNG as a marine fuel, as a means to comply with sulfur and NOX regulations. Particles were studied in a wide size range together with measurements of other exhaust gases under different engine loads and different mixtures of LNG and marine gas oil. Results from these measurements show that emissions of particles, NOX, and CO2 are considerably lower for LNG compared to present marine fuel oils. Emitted particles were mainly of volatile character and mainly had diameters below 50 nm. Number size distribution for LNG showed a distinct peak at 9-10 nm and a part of a peak at diameter 6 nm and below. Emissions of total hydrocarbons and carbon monoxide are higher for LNG compared to present marine fuel oils, which points to the importance of considering the methane slip from combustion of LNG.

  6. Online measurements of the emissions of intermediate-volatility and semi-volatile organic compounds from aircraft

    NASA Astrophysics Data System (ADS)

    Cross, E. S.; Hunter, J. F.; Carrasquillo, A. J.; Franklin, J. P.; Herndon, S. C.; Jayne, J. T.; Worsnop, D. R.; Miake-Lye, R. C.; Kroll, J. H.

    2013-03-01

    A detailed understanding of the climate and air quality impacts of aviation requires detailed measurements of the emissions of intermediate-volatility and semi-volatile organic compounds (I/SVOCs) from aircraft. Currently both the amount and chemical composition of aircraft I/SVOC emissions remain poorly characterized. Here we characterize I/SVOC emissions from aircraft, using a novel instrument for the online, quantitative measurement of the mass loading and composition of low-volatility organic vapors. Emissions from the NASA DC8 aircraft were sampled on the ground, 143 m downwind of the engines and characterized as a function of engine power from ground idle (~4% maximum rated thrust) through 85% power. Results show that I/SVOC emissions are highest during engine-idle operating conditions, with decreasing but non-zero I/SVOC emissions at higher engine powers. Comparison of I/SVOC emissions with total hydrocarbon (THC) measurements, VOC measurements, and an established emissions profile indicates that I/SVOCs comprise 10-20% of the total organic gas phase emissions at idle, and an increasing fraction of the total gas phase organic emissions at higher powers. Positive matrix factorization of online mass spectra is used to identify three distinct types of I/SVOC emissions: aliphatic, aromatic and oxygenated. The volatility and chemical composition of the emissions suggest that unburned fuel is the dominant source of I/SVOCs at idle, while pyrolysis products make up an increasing fraction of the I/SVOCs at higher powers. Oxygenated I/SVOC emissions were detected at lower engine powers (≤30%) and may be linked to cracked, partially oxidized or unburned fuel components.

  7. Online measurements of the emissions of intermediate-volatility and semi-volatile organic compounds from aircraft

    NASA Astrophysics Data System (ADS)

    Cross, E. S.; Hunter, J. F.; Carrasquillo, A. J.; Franklin, J. P.; Herndon, S. C.; Jayne, J. T.; Worsnop, D. R.; Miake-Lye, R. C.; Kroll, J. H.

    2013-08-01

    A detailed understanding of the climate and air quality impacts of aviation requires measurements of the emissions of intermediate-volatility and semi-volatile organic compounds (I/SVOCs) from aircraft. Currently both the amount and chemical composition of aircraft I/SVOC emissions remain poorly characterized. Here we characterize I/SVOC emissions from aircraft, using a novel instrument for the online, quantitative measurement of the mass loading and composition of low-volatility organic vapors. Emissions from the NASA DC8 aircraft were sampled on the ground 143 m downwind of the engines and characterized as a function of engine power from idle (4% maximum rated thrust) through 85% power. Results show that I/SVOC emissions are highest during engine idle operating conditions, with decreasing but non-zero I/SVOC emissions at higher engine powers. Comparison of I/SVOC emissions with total hydrocarbon (THC) measurements, VOC measurements, and an established emissions profile indicates that I/SVOCs comprise 10-20% of the total organic gas-phase emissions at idle, and an increasing fraction of the total gas-phase organic emissions at higher powers. Positive matrix factorization of online mass spectra is used to identify three distinct types of I/SVOC emissions: aliphatic, aromatic and oxygenated. The volatility and chemical composition of the emissions suggest that unburned fuel is the dominant source of I/SVOCs at idle, while pyrolysis products make up an increasing fraction of the I/SVOCs at higher powers. Oxygenated I/SVOC emissions were detected at lower engine powers (≤30%) and may be linked to cracked, partially oxidized or unburned fuel components.

  8. Emissions of fine particle fluoride from biomass burning.

    PubMed

    Jayarathne, Thilina; Stockwell, Chelsea E; Yokelson, Robert J; Nakao, Shunsuke; Stone, Elizabeth A

    2014-11-04

    The burning of biomasses releases fluorine to the atmosphere, representing a major and previously uncharacterized flux of this atmospheric pollutant. Emissions of fine particle (PM2.5) water-soluble fluoride (F-) from biomass burning were evaluated during the fourth Fire Laboratory at Missoula Experiment (FLAME-IV) using scanning electron microscopy energy dispersive X-ray spectroscopy (SEM-EDX) and ion chromatography with conductivity detection. F- was detected in 100% of the PM2.5 emissions from conifers (n=11), 94% of emissions from agricultural residues (n=16), and 36% of the grasses and other perennial plants (n=14). When F- was quantified, it accounted for an average (±standard error) of 0.13±0.02% of PM2.5. F- was not detected in remaining samples (n=15) collected from peat burning, shredded tire combustion, and cook-stove emissions. Emission factors (EF) of F- emitted per kilogram of biomass burned correlated with emissions of PM2.5 and combustion efficiency, and also varied with the type of biomass burned and the geographic location where it was harvested. Based on recent evaluations of global biomass burning, we estimate that biomass burning releases 76 Gg F- yr(-1) to the atmosphere, with upper and lower bounds of 40-150 Gg F- yr(-1). The estimated F- flux from biomass burning is comparable to total fluorine emissions from coal combustion plus other anthropogenic sources. These data demonstrate that biomass burning represents a major source of fluorine to the atmosphere in the form of fine particles, which have potential to undergo long-range transport.

  9. Aqueous Processing of Atmospheric Organic Particles in Cloud Water Collected via Aircraft Sampling.

    PubMed

    Boone, Eric J; Laskin, Alexander; Laskin, Julia; Wirth, Christopher; Shepson, Paul B; Stirm, Brian H; Pratt, Kerri A

    2015-07-21

    Cloudwater and below-cloud atmospheric particle samples were collected onboard a research aircraft during the Southern Oxidant and Aerosol Study (SOAS) over a forested region of Alabama in June 2013. The organic molecular composition of the samples was studied to gain insights into the aqueous-phase processing of organic compounds within cloud droplets. High resolution mass spectrometry (HRMS) with nanospray desorption electrospray ionization (nano-DESI) and direct infusion electrospray ionization (ESI) were utilized to compare the organic composition of the particle and cloudwater samples, respectively. Isoprene and monoterpene-derived organosulfates and oligomers were identified in both the particles and cloudwater, showing the significant influence of biogenic volatile organic compound oxidation above the forested region. While the average O:C ratios of the organic compounds were similar between the atmospheric particle and cloudwater samples, the chemical composition of these samples was quite different. Specifically, hydrolysis of organosulfates and formation of nitrogen-containing compounds were observed for the cloudwater when compared to the atmospheric particle samples, demonstrating that cloud processing changes the composition of organic aerosol.

  10. Aqueous Processing of Atmospheric Organic Particles in Cloud Water Collected via Aircraft Sampling

    SciTech Connect

    Boone, Eric J.; Laskin, Alexander; Laskin, Julia; Wirth, Christopher; Shepson, Paul B.; Stirm, Brian H.; Pratt, Kerri A.

    2015-07-21

    Cloud water and below-cloud atmospheric particle samples were collected onboard a research aircraft during the Southern Oxidant and Aerosol Study (SOAS) over a forested region of Alabama in June 2013. The organic molecular composition of the samples was studied to gain insights into the aqueous-phase processing of organic compounds within cloud droplets. High resolution mass spectrometry with nanospray desorption electrospray ionization and direct infusion electrospray ionization were utilized to compare the organic composition of the particle and cloud water samples, respectively. Isoprene and monoterpene-derived organosulfates and oligomers were identified in both the particles and cloud water, showing the significant influence of biogenic volatile organic compound oxidation above the forested region. While the average O:C ratios of the organic compounds were similar between the atmospheric particle and cloud water samples, the chemical composition of these samples was quite different. Specifically, hydrolysis of organosulfates and formation of nitrogen-containing compounds were observed for the cloud water when compared to the atmospheric particle samples, demonstrating that cloud processing changes the composition of organic aerosol.

  11. Particle and gaseous emissions from individual diesel and CNG buses

    NASA Astrophysics Data System (ADS)

    Hallquist, Å. M.; Jerksjö, M.; Fallgren, H.; Westerlund, J.; Sjödin, Å.

    2013-05-01

    In this study size-resolved particle and gaseous emissions from 28 individual diesel-fuelled and 7 compressed natural gas (CNG)-fuelled buses, selected from an in-use bus fleet, were characterised for real-world dilution scenarios. The method used was based on using CO2 as a tracer of exhaust gas dilution. The particles were sampled by using an extractive sampling method and analysed with high time resolution instrumentation EEPS (10 Hz) and CO2 with a non-dispersive infrared gas analyser (LI-840, LI-COR Inc. 1 Hz). The gaseous constituents (CO, HC and NO) were measured by using a remote sensing device (AccuScan RSD 3000, Environmental System Products Inc.). Nitrogen oxides, NOx, were estimated from NO by using default NO2/NOx ratios from the road vehicle emission model HBEFA3.1. The buses studied were diesel-fuelled Euro III-V and CNG-fuelled Enhanced Environmentally Friendly Vehicles (EEVs) with different after-treatment, including selective catalytic reduction (SCR), exhaust gas recirculation (EGR) and with and without diesel particulate filter (DPF). The primary driving mode applied in this study was accelerating mode. However, regarding the particle emissions also a constant speed mode was analysed. The investigated CNG buses emitted on average a higher number of particles but less mass compared to the diesel-fuelled buses. Emission factors for number of particles (EFPN) were EFPN, DPF = 4.4 ± 3.5 × 1014, EFPN, no DPF = 2.1 ± 1.0 × 1015 and EFPN, CNG = 7.8 ± 5.7 ×1015 kg fuel-1. In the accelerating mode, size-resolved emission factors (EFs) showed unimodal number size distributions with peak diameters of 70-90 nm and 10 nm for diesel and CNG buses, respectively. For the constant speed mode, bimodal average number size distributions were obtained for the diesel buses with peak modes of ~10 nm and ~60 nm. Emission factors for NOx expressed as NO2 equivalents for the diesel buses were on average 27 ± 7 g (kg fuel)-1 and for the CNG buses 41 ± 26 g (kg

  12. Probing Aircraft Flight Test Hazard Mitigation for the Alternative Fuel Effects on Contrails & Cruise Emissions (ACCESS) Research Team

    NASA Technical Reports Server (NTRS)

    Kelly, Michael J.

    2013-01-01

    The Alternative Fuel Effects on Contrails & Cruise Emissions (ACCESS) Project Integration Manager requested in July 2012 that the NASA Engineering and Safety Center (NESC) form a team to independently assess aircraft structural failure hazards associated with the ACCESS experiment and to identify potential flight test hazard mitigations to ensure flight safety. The ACCESS Project Integration Manager subsequently requested that the assessment scope be focused predominantly on structural failure risks to the aircraft empennage raft empennage.

  13. 76 FR 45011 - Control of Air Pollution From Aircraft and Aircraft Engines; Proposed Emission Standards and Test...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-07-27

    ... Environmental Protection Agency 40 CFR Parts 87 and 1068 Control of Air Pollution From Aircraft and Aircraft... AGENCY 40 CFR Parts 87 and 1068 [EPA-HQ-OAR-2010-0687; FRL-9437-2] RIN 2060-AO70 Control of Air Pollution... engines which in her judgment causes or contributes to air pollution that may reasonably be anticipated...

  14. [Size distribution of particle and polycyclic aromatic hydrocarbons in particle emissions from simulated emission sources].

    PubMed

    Fu, Hai-Huan; Tian, Na; Shang, Hui-Bin; Zhang, Bin; Ye, Su-Fen; Chen, Xiao-Qiu; Wu, Shui-Ping

    2014-01-01

    Particles from cooking lampblack, biomass and plastics burning smoke, gasoline vehicular exhausts and gasoline generator exhausts were prepared in a resuspension test chamber and collected using a cascade MOUDI impactor. A total of 18 polycyclic aromatic hydrocarbons (PAHs) associated with particles were analyzed by GC-MS. The results showed that there were two peaks in the range of 0.44-1.0 microm and 2.5-10 microm for cooking lampblack, and only one peak in the range of 0.44-1.0 microm for straw and wood burning smoke. But there were no clear peak for plastics burning smoke. The peak for gasoline vehicular exhausts was found in the range of 2.5-10 microm due to the influence of water vapor associated with particles, while the particles from gasoline generator exhausts were mainly in the range of < or = 2.5 microm (accounting for 93% of the total mass). The peak in 2.5-10 microm was clear for cooking lampblack and gasoline vehicular exhausts. The peak in the range of 0.44-1.0 microm became more and more apparent with the increase of PAHs molecular weight. The fraction of PAH on particles less than 1.0 microm to that on the total particles increased along with PAH's molecular weight. Phenanthrene was the dominant compound for cooking lampblack and combustion smoke, while gasoline vehicular exhausts and generator exhausts were characterized with significantly high levels of naphthalene and benzo[g, h, i] perylene, respectively. The distribution of source characteristic ratios indicated that PAHs from cooking lampblack and biomass burning were close and they were different from those of vehicular exhausts and generator exhausts.

  15. Quantifying emerging local anthropogenic emissions in the Arctic region: the ACCESS aircraft campaign experiment

    NASA Astrophysics Data System (ADS)

    Roiger, Anke; Thomas, Jennie L.; Schlager, Hans; Law, Kathy; Kim, Jin; Reiter, Anja; Schäfler, Andreas; Weinzierl, Bernadett; Rose, Maximilian; Raut, Jean-Christophe; Marelle, Louis

    2014-05-01

    Arctic change has opened the region to new industrial activities, most notably transit shipping and resource extraction. The impacts that Arctic industrialization will have on pollutants and Arctic climate are not well understood. In order to understand how shipping and offshore oil/gas extraction impact on Arctic tropospheric chemistry and composition, we conducted the ACCESS (Arctic Climate Change, Economy, and Society, a European Union Seventh Framework Programme project) aircraft campaign. The campaign was conducted in July 2012 using the DLR Falcon research aircraft, based in Andenes, Norway. The Falcon was equipped with a suite of trace gas and aerosol instruments (black carbon, ozone, as well as other trace species) to characterize these emissions and their atmospheric chemistry. The Falcon performed nine scientific flights to study emissions from different ships (e.g. cargo, passenger, and fishing vessels) and a variety of offshore extraction facilities (e.g. drilling rigs, production and storage platforms) off the Norwegian Coast. Distinct differences in chemical and aerosol composition were found in emissions from these increasing pollution sources. We also studied the composition of biomass burning plumes imported from Siberian wildfires to put the emerging local pollution within a broader context. In addition to our measurements, we used a regional chemical transport model to study the influence of emerging pollution sources on gas and aerosol concentrations in the region. We will present an overview on the measured trace gas and aerosol properties of the different emission sources and discuss the impact of future local anthropogenic activities on the Arctic air composition by combining measurements with model simulations.

  16. Particle and gaseous emissions from individual diesel and CNG buses

    NASA Astrophysics Data System (ADS)

    Hallquist, Å. M.; Jerksjö, M.; Fallgren, H.; Westerlund, J.; Sjödin, Å.

    2012-10-01

    In this study size-resolved particle and gaseous emissions from 28 individual diesel-fuelled and 7 compressed natural gas (CNG)-fuelled buses, selected from an in-use bus fleet, were characterised for real-world dilution scenarios. The method used was based on using CO2 as a tracer of exhaust gas dilution. The particles were sampled by using an extractive sampling method and analysed with high time resolution instrumentation EEPS (10 Hz) and CO2 with non-dispersive infrared gas analyser (LI-840, LI-COR Inc. 1 Hz). The gaseous constituents (CO, HC and NO) were measured by using a remote sensing device (AccuScan RSD 3000, Environmental System Products Inc.). Nitrogen oxides, NOx, were estimated from NO by using default NO2/NOx ratios from the road vehicle emission model HBEFA 3.1. The buses studied were diesel-fuelled Euro II-V and CNG-fuelled Enhanced Environmental Friendly Vehicles (EEVs) with different after-treatment, including selective catalytic reduction (SCR), exhaust gas recirculation (EGR) and with and without diesel particulate filter (DPF). The primary driving mode applied in this study was accelerating mode. However, regarding the particle emissions also a constant speed mode was analysed. The investigated CNG buses emitted on average higher number of particles but less mass compared to the diesel-fuelled buses. Emission factors for number of particles (EFPN) were EFPN, DPF = 8.0 ± 3.1 × 1014, EFPN, no DPF =2.8 ± 1.6 × 1015 and EFPN, CNG = 7.8 ± 5.7 × 1015 (kg fuel-1). In the accelerating mode size-resolved EFs showed unimodal number size distributions with peak diameters of 70-90 nm and 10 nm for diesel and CNG buses, respectively. For the constant speed mode bimodal average number size distributions were obtained for the diesel buses with peak modes of ~10 nm and ~60 nm. Emission factors for NOx expressed as NO2 equivalents for the diesel buses were on average 27 ± 7 g (kg fuel)-1 and for the CNG buses 41 ± 26 g (kg fuel)-1. An anti

  17. Effects of Fuel Aromatic Content on Nonvolatile Particulate Emissions of an In-Production Aircraft Gas Turbine.

    PubMed

    Brem, Benjamin T; Durdina, Lukas; Siegerist, Frithjof; Beyerle, Peter; Bruderer, Kevin; Rindlisbacher, Theo; Rocci-Denis, Sara; Andac, M Gurhan; Zelina, Joseph; Penanhoat, Olivier; Wang, Jing

    2015-11-17

    Aircraft engines emit particulate matter (PM) that affects the air quality in the vicinity of airports and contributes to climate change. Nonvolatile PM (nvPM) emissions from aircraft turbine engines depend on fuel aromatic content, which varies globally by several percent. It is uncertain how this variability will affect future nvPM emission regulations and emission inventories. Here, we present black carbon (BC) mass and nvPM number emission indices (EIs) as a function of fuel aromatic content and thrust for an in-production aircraft gas turbine engine. The aromatics content was varied from 17.8% (v/v) in the neat fuel (Jet A-1) to up to 23.6% (v/v) by injecting two aromatic solvents into the engine fuel supply line. Fuel normalized BC mass and nvPM number EIs increased by up to 60% with increasing fuel aromatics content and decreasing engine thrust. The EIs also increased when fuel naphthalenes were changed from 0.78% (v/v) to 1.18% (v/v) while keeping the total aromatics constant. The EIs correlated best with fuel hydrogen mass content, leading to a simple model that could be used for correcting fuel effects in emission inventories and in future aircraft engine nvPM emission standards.

  18. Determination of major combustion products in aircraft exhausts by FTIR emission spectroscopy

    NASA Astrophysics Data System (ADS)

    Heland, J.; Schäfer, K.

    The results of ground-based FTIR emission measurements of major combustion products such as CO 2, H 2O, CO, NO, and N 2O of in-service aircraft engines are reported and compared to values published in recent literature. About 25% differences in the NO and CO emission indices at several power settings were found for two military bypass engines of the same type. In addition the measured CO emission index of (51.8±4.6) g kg -1 at idle power of a CFM56-3 engine was about 27% lower than the value given by Spicer et al. (1984, 1994)for this engine type and about 27-48% higher than the ICAO data ( ICAO, 1995) for the whole span of CFM56-3 engines. The CO emission index measured at idle power of a CFM56-5C2 engine of AN Airbus A340 was (24±4) g kg -1 and can be compared to the ICAO value of 34 g kg -1. The N 2O mixing ratios measured at a higher power setting of this engine was found to be 4 ppm and is in the range of reported literature values. Since the NO and CO emissions are strongly connected to the combustion process/efficiency and thus to the state of engine maintainance and/or the engine age, it can be concluded that there are significant engine-to-engine (of the same type) and possibly day-to-day variations in the emission characteristics of aero engines which cannot be neglected for the estimation of the overall air-traffic emissions.

  19. Quantifying emerging local anthropogenic emissions in the Arctic region: the ACCESS aircraft campaign experiment (Invited)

    NASA Astrophysics Data System (ADS)

    Roiger, A.; Thomas, J. L.; Schlager, H.; Law, K.; Kim, J.; Reiter, A.; Schaefler, A.; Weinzierl, B.; Rose, M.; Raut, J.; Marelle, L.

    2013-12-01

    Arctic sea ice has decreased dramatically in the past few decades, which has opened the Arctic Ocean to transit shipping and hydrocarbon extraction. These anthropogenic activities are expected to increase emissions of air pollutants and climate forcers (e.g. aerosols, ozone) in the Arctic troposphere significantly in the future. However, large knowledge gaps exist how these emissions influence regional air pollution and Arctic climate. Here we present an overview on the ACCESS (Arctic Climate Change, Economy, and Society, a European Union Seventh Framework Programme project) aircraft campaign, which primarily focused on studying emissions from emerging Arctic pollution sources. During the ACCESS campaign in July 2012, the DLR Falcon was based in Andenes, Norway, and was equipped with a suite of trace gas and aerosol instruments (black carbon, ozone, as well as other trace species). During nine scientific flights, emissions from different ship types (e.g. cargo, passenger, and fishing vessels) and a variety of offshore extraction facilities (e.g. drilling rigs, production and storage platforms) were probed off the Norwegian Coast. The emissions from these increasing pollution sources showed distinct differences in chemical and aerosol composition. To put the emerging local pollution within a broader context, we also measured sulfur-rich emissions originating from industrial activities on the Kola Peninsula and black carbon containing biomass burning plumes imported from Siberian wildfires. We will present an overview on the trace gas and aerosol properties of the different emission sources, and discuss the influence of future local anthropogenic activities on the Arctic air composition by combining measurements with model simulations.

  20. Comparison of impacts of aircraft emissions within the boundary layer on the regional ozone in South Korea

    NASA Astrophysics Data System (ADS)

    Song, Sang-Keun; Shon, Zang-Ho; Kang, Yoon-Hee

    2015-09-01

    In this study, the air pollutants emitted from aircraft within the boundary layer (BL) were investigated for their impacts on the ozone (O3) concentration at and around three international airports (Incheon, RKSI; Gimpo, RKSS; and Jeju, RKPC) using the WRF-CMAQ modeling system during the summer of 2010. The analysis was performed using two sets of simulation scenarios: (1) with (i.e., TOTAL case) and (2) without aircraft emissions (i.e., BASE case). The model study suggested that aircraft emissions within the BL over the three airports can have a significant impact on the O3 (and NOx) concentrations in the source regions (the airports) and their surrounding/downwind areas. A significant negative impact of aircraft emissions on the O3 concentrations in the late afternoon (19:00 LST) was predicted near the three airports with their largest impact of -20 ppb near the RKSI at 19:00 LST. This was attributed mainly to the high NOx conditions in the VOC-limited areas and possibly in part to the rapid titration of O3 by NO around these airports. The rate of photochemical O3 destruction due to the aircraft emissions near the three airports was the most dominant contributor to the O3 levels compared to the other physical processes.

  1. In-Flight Chemical Composition Observations of Aircraft Emissions using a High-Resolution Time-of-Flight Aerosol Mass Spectrometer

    NASA Astrophysics Data System (ADS)

    Ziemba, L. D.; Martin, R.; Moore, R.; Shook, M.; Thornhill, K. L., II; Winstead, E.; Anderson, B. E.

    2015-12-01

    Commercial aircraft are an important source of aerosols to the upper troposphere. The microphysical and chemical properties of these emitted aerosols govern their ability to act as ice nuclei, both in near-field contrails and for cirrus formation downstream. During the ACCESS-II (Alternative Fuel Effects on Contrails and Cruise Emissions) campaign, NASA DC-8 CFM56-2-C1 engine emissions were sampled systematically at a range of cruise-relevant thrust levels and at several altitudes. Sampling was done aboard the NASA HU-25 Falcon aircraft, which was equipped with a suite of aerosol and gas-phase instruments focused on assessing the effects of burning different fuel mixtures on aerosol properties and their associated contrails. Here we present in-flight measurements of particle chemical composition made by a High-Resolution Time-of-Flight Aerosol Mass Spectrometer (HR-ToF-AMS). The AMS was able to sufficiently resolve near-field (within 100m) aircraft emissions plumes. Low-sulfur HEFA (hydro-processed esters and fatty-acids) and JetA fuels yielded particles that contained 11 and 8% sulfate, respectively, compared to 30% sulfate contribution for traditional JetA fuel. Each of the fuels produced organic aerosol with similarly low oxygen content. Lubrication oils, which are not a combustion product but result from leaks in the engine, were likely a dominant fraction of the measured organic mass based on mass-spectral marker analysis. These results are compared to similar engine conditions from ground-based testing.

  2. Emission Reduction of Fuel-Staged Aircraft Engine Combustor Using an Additional Premixed Fuel Nozzle.

    PubMed

    Yamamoto, Takeshi; Shimodaira, Kazuo; Yoshida, Seiji; Kurosawa, Yoji

    2013-03-01

    The Japan Aerospace Exploration Agency (JAXA) is conducting research and development on aircraft engine technologies to reduce environmental impact for the Technology Development Project for Clean Engines (TechCLEAN). As a part of the project, combustion technologies have been developed with an aggressive target that is an 80% reduction over the NOx threshold of the International Civil Aviation Organization (ICAO) Committee on Aviation Environmental Protection (CAEP)/4 standard. A staged fuel nozzle with a pilot mixer and a main mixer was developed and tested using a single-sector combustor under the target engine's landing and takeoff (LTO) cycle conditions with a rated output of 40 kN and an overall pressure ratio of 25.8. The test results showed a 77% reduction over the CAEP/4 NOx standard. However, the reduction in smoke at thrust conditions higher than the 30% MTO condition and of CO emission at thrust conditions lower than the 85% MTO condition are necessary. In the present study, an additional fuel burner was designed and tested with the staged fuel nozzle in a single-sector combustor to control emissions. The test results show that the combustor enables an 82% reduction in NOx emissions relative to the ICAO CAEP/4 standard and a drastic reduction in smoke and CO emissions.

  3. Calculations and observations of solar particle enhancements to the radiation environment at aircraft altitudes.

    PubMed

    Dyer, C S; Lei, F; Clucas, S N; Smart, D F; Shea, M A

    2003-01-01

    Solar particle events can give greatly enhanced radiation at aircraft altitudes, but are both difficult to predict and to calculate retrospectively. This enhanced radiation can give significant dose to aircrew and greatly increase the rate of single event effects in avionics. Validation of calculations is required but only very few events have been measured in flight. The CREAM detector on Concorde detected the event of 29 September 1989 and also four periods of enhancement during the events of 19-24 October 1989. Instantaneous rates were enhanced by up to a factor ten compared with quiet-time cosmic rays, while flight-averages were enhanced by up to a factor six. Calculations are described for increases in radiation at aircraft altitudes using solar particle spectra in conjunction with Monte Carlo radiation transport codes. In order to obtain solar particle spectra with sufficient accuracy over the required energy range it is necessary to combine space data with measurements from a wide range of geomagnetically dispersed, ground-level neutron monitors. Such spectra have been obtained for 29 September 1989 and 24 October 1989 and these are used to calculate enhancements that are compared with the data from CREAM on Concorde. The effect of cut-off rigidity suppression by geomagnetic activity is shown to be significant. For the largest event on record on 23 February 1956, there are no space data but there are data from a number of ground-level cosmic-ray detectors. Predictions for all events show very steep dependencies on both latitude and altitude. At high latitude and altitude (17 km) calculated increases with respect to cosmic rays are a factor 70 and 500 respectively for 29 September 1989 and 23 February 1956. The levels of radiation for high latitude, subsonic routes are calculated, using London to Los Angeles as an example, and can exceed 1 mSv, which is significantly higher than for Concorde routes from Europe to New York. The sensitivity of the calculations

  4. Humidity control of particle emissions in aeolian systems

    NASA Astrophysics Data System (ADS)

    McKenna Neuman, Cheryl; Sanderson, Steven

    2008-06-01

    Humidity is an important control of the wind speed required to entrain particles into an air flow and is well known to vary on a global scale, as do dust emissions. This paper reports on wind tunnel experiments which quantify this control through placing a polymer capacitance sensor immediately at the bed surface. The sensor measured changes in the humidity (RH) of the pore air in real time. RH was varied between 15% and 80% and the critical wind speed determined for the release of particles to the air stream. The results strongly support earlier suggestions that fine particles are most affected in relatively dry atmospheres, particularly those which are tightly packed. An analytical model is proposed to describe this relationship which depends on determination of the matric potential from the Kelvin equation. The total contact area between particle asperities adjoined by pendular rings is represented as a power function of the number of layers of adsorbed water. The value of the exponent appears to be governed by the surface roughness of the particles and their packing arrangement. Parallel developments in colloid interface science and atomic force microscopy, relevant to industrial and pharmaceutical applications, support these conclusions in principle and will likely have an important bearing on future progress in parameterization of the proposed model.

  5. Characterizing the impact of urban emissions on regional aerosol particles: airborne measurements during the MEGAPOLI experiment

    NASA Astrophysics Data System (ADS)

    Freney, E. J.; Sellegri, K.; Canonaco, F.; Colomb, A.; Borbon, A.; Michoud, V.; Doussin, J.-F.; Crumeyrolle, S.; Amarouche, N.; Pichon, J.-M.; Bourianne, T.; Gomes, L.; Prevot, A. S. H.; Beekmann, M.; Schwarzenböeck, A.

    2014-02-01

    The MEGAPOLI (Megacities: Emissions, urban, regional and Global Atmospheric POLlution and climate effects, and Integrated tools for assessment and mitigation) experiment took place in July 2009. The aim of this campaign was to study the aging and reactions of aerosol and gas-phase emissions in the city of Paris. Three ground-based measurement sites and several mobile platforms including instrument equipped vehicles and the ATR-42 aircraft were involved. We present here the variations in particle- and gas-phase species over the city of Paris, using a combination of high-time resolution measurements aboard the ATR-42 aircraft. Particle chemical composition was measured using a compact time-of-flight aerosol mass spectrometer (C-ToF-AMS), giving detailed information on the non-refractory submicron aerosol species. The mass concentration of black carbon (BC), measured by a particle absorption soot photometer (PSAP), was used as a marker to identify the urban pollution plume boundaries. Aerosol mass concentrations and composition were affected by air-mass history, with air masses that spent longest time over land having highest fractions of organic aerosol and higher total mass concentrations. The Paris plume is mainly composed of organic aerosol (OA), BC, and nitrate aerosol, as well as high concentrations of anthropogenic gas-phase species such as toluene, benzene, and NOx. Using BC and CO as tracers for air-mass dilution, we observe the ratio of ΔOA / ΔBC and ΔOA / ΔCO increase with increasing photochemical age (-log(NOx / NOy)). Plotting the equivalent ratios of different organic aerosol species (LV-OOA, SV-OOA, and HOA) illustrate that the increase in OA is a result of secondary organic aerosol (SOA) formation. Within Paris the changes in the ΔOA / ΔCO are similar to those observed during other studies in London, Mexico City, and in New England, USA. Using the measured SOA volatile organic compounds (VOCs) species together with organic aerosol formation

  6. [Analysis on oil fume particles in catering industry cooking emission].

    PubMed

    Tan, De-Sheng; Kuang, Yuan-Cheng; Liu, Xin; Dai, Fei-Hong

    2012-06-01

    By measuring the particulate matter of oil fume which is over 10 microm or below 10 microm separately and using microradiography and Electrical Low Pressure Impactor (ELPI), it is found out the distributing characteristic of oil fume particles in catering industry cooking emission. The result shows that the diameter of the oil fume particles which was sedimentated in the kitchen is between 10-400 microm, the concentration peak value is between 10-100 microm. The diameter of oil fume aerosol is mostly smaller than 1 microm, while the concentration peak value is between 0.063-0.109 microm. In addition, the mass concentration peak value is between 6.560-9.990 microm. Through the analysis to the physical characteristics of oil fume from catering industry cooking emissions, the eigenvalue of the oil fume has been found and the feature matter for monitoring the oil fume has been discovered to provide a reasonable standard for controlling and monitoring the catering industry cooking emission.

  7. Behavior of Catalyst Particle at Tip of Carbon Nanotube during Field Emission

    NASA Astrophysics Data System (ADS)

    Fujieda, Tadashi; Okai, Makoto; Hidaka, Kishio; Matsumoto, Hiroaki; Tokumoto, Hiroshi

    2008-01-01

    A catalyst particle at the tip of a multi-walled carbon nanotube (MWNT) during field emission inside a transmission electron microscope was observed in-situ. The particle streamed from the tip like a liquid as the emission current abruptly increased from 20 to 40 µA. This was due to the temperature rise at the tip of the MWNT, resulting from the increased emission current and dipole moment in the particle caused by the electric field. Maintenance of this high emission current led to an electrical discharge, which severely damaged the MWNT electron emitter. Under high emission currents, in particular, the catalyst particle caused an unstable emission.

  8. Time-resolved characterization of primary particle emissions and secondary particle formation from a modern gasoline passenger car

    NASA Astrophysics Data System (ADS)

    Karjalainen, Panu; Timonen, Hilkka; Saukko, Erkka; Kuuluvainen, Heino; Saarikoski, Sanna; Aakko-Saksa, Päivi; Murtonen, Timo; Bloss, Matthew; Dal Maso, Miikka; Simonen, Pauli; Ahlberg, Erik; Svenningsson, Birgitta; Brune, William Henry; Hillamo, Risto; Keskinen, Jorma; Rönkkö, Topi

    2016-07-01

    Changes in vehicle emission reduction technologies significantly affect traffic-related emissions in urban areas. In many densely populated areas the amount of traffic is increasing, keeping the emission level high or even increasing. To understand the health effects of traffic-related emissions, both primary (direct) particulate emission and secondary particle formation (from gaseous precursors in the exhaust emissions) need to be characterized. In this study, we used a comprehensive set of measurements to characterize both primary and secondary particulate emissions of a Euro 5 level gasoline passenger car. Our aerosol particle study covers the whole process chain in emission formation, from the tailpipe to the atmosphere, and also takes into account differences in driving patterns. We observed that, in mass terms, the amount of secondary particles was 13 times higher than the amount of primary particles. The formation, composition, number and mass of secondary particles was significantly affected by driving patterns and engine conditions. The highest gaseous and particulate emissions were observed at the beginning of the test cycle when the performance of the engine and the catalyst was below optimal. The key parameter for secondary particle formation was the amount of gaseous hydrocarbons in primary emissions; however, also the primary particle population had an influence.

  9. [Emission characteristics of fine particles from grate firing boilers].

    PubMed

    Wang, Shu-Xiao; Zhao, Xiu-Juan; Li, Xing-Hua; Wei, Wei; Hao, Ji-Ming

    2009-04-15

    Grate firing boilers are the main type of Chinese industrial boilers, which accounts for 85% of the industrial boilers and is one of the most important emission sources of primary air pollutants in China. In this study, five boilers in three cities were selected and tested to measure the emission characteristics of PM2.5, and gaseous pollutants were applied by a compact dilution sampling system, which was developed for this field study. Results showed that particles mass size distributions for the five industrial boilers presented single peak or double peak, former peaks near 0.14 microm and the later peaks after 1.0 microm; the cyclone dust remover and wet scrubber dust remover had effective removal efficiencies not only to PM2.5, but also to PM1.0; and under the condition of same control techniques, grate firing boiler with high capacity has less PM2.5 emission than the boiler with low capacity. In the PM2.5 collected from flue gases, SO4(2-) was the most abundant ion, accounted for 20%-40% of the PM2.5; and C was the most abundant element (7.5%-31.8%), followed by S (8.4%-18.7%). Carbon balance method was applied to calculate the emission factors of these pollutants. The emission factors of PM2.5, NO, and SO2 were in the range of 0.046-0.486 g x kg(-1), 1.63-2.47 g x kg(-1), 1.35-9.95 g x kg(-1) respectively. The results are useful for the emission inventory development of industrial boilers and the source analysis of PM2.5 in atmospheric environment.

  10. Rapid Measurement of Emissions From Military Aircraft Turbine Engines by Downstream Extractive Sampling of Aircraft on the Ground: Results for C-130 and F-15 Aircraft (POSTPRINT)

    DTIC Science & Technology

    2009-02-01

    engines were tested using indoor engine test facilities (F110, F101, J85 -GE-5M, PT6A-68, TF41-A2, TF30-P103 and TF30- P109), while others were studied while...afterburning). Engine T56-A-15 F100-PW-100 F110 F101 J85 -GE-5M PT6A-68 TF-39-1C CFM-56-3 TF41-A2 TF30-P103 TF30-P109 Misc. Type Turboprop Turbofan...AIRCRAFT TURBINE ENGINES BY DOWNSTREAM EXTRACTIVE SAMPLING OF AIRCRAFT ON THE GROUND: RESULTS FOR C-130 AND F-15 AIRCRAFT Chester Spicer and

  11. Particle Acceleration and Nonthermal Emission in Relativistic Astrophysical Shocks

    NASA Astrophysics Data System (ADS)

    Sironi, Lorenzo

    alternating fields to the particles, generating flat power-law tails containing most of the particles. Finally, I directly relate the results of my PIC simulations to observations of nonthermal sources, by presenting a numerical technique that I have developed in order to extract ab initio photon spectra from PIC simulations of shocks. With this technique, I have modeled the emission from GRB jets, ruling out a class of models that relied on the so-called jitter radiation. This reinforces the idea that a detailed understanding of the micro-physics of particle acceleration in relativistic shocks is required in order to correctly interpret the emission signatures of astrophysical nonthermal sources.

  12. An aircraft-based case study of new particle formation and growth in the summertime Arctic

    NASA Astrophysics Data System (ADS)

    Willis, M. D.; Abbatt, J.; Burkart, J.; Bozem, H.; Koellner, F.; Schneider, J.; Hoor, P. M.; Herber, A. B.; Leaitch, W. R.

    2015-12-01

    Motivated by the changing climate of the Arctic and decreasing summer sea-ice extent, we aim to better understand how atmospheric composition will impact, or be impacted by, climate and environmental change in this region. Much attention has been paid to springtime Arctic aerosol owing to significant anthropogenic influence on this remote environment, but the cleaner, more locally influenced summertime Arctic is not well characterized. We present results of vertically resolved, particle number, aerosol size distributions, submicron aerosol composition from an aerosol mass spectrometer (AMS), and cloud condensation nuclei (CCN) concentrations from the NETCARE 2014 Polar 6 aircraft campaign. The campaign was based in the high Arctic, at Resolute Bay, Nunavut, Canada (74°N, 94°W), allowing measurements from 60 to 2900 meters over ice, open water and near the ice-edge. The focus of this case study is a new particle formation and growth event observed at the eastern end of Lancaster Sound (74°N, 81°W) on July 12, 2014 under clear sky conditions. During this flight Polar 6 travelled to the end of Lancaster Sound at 2900 m and subsequently descended to 60-70 m above the surface heading due west, with winds from the west. At the lowest altitude we observed a significant increase in particles > 4 nm, between 20 - 100 nm, and > 100 nm, indicating the presence of small particles between 4 - 20 nm and growth to larger sizes. In addition, CCN concentrations were enhanced up to ~ 200/cm3 from background levels of ≤ 100/cm3. Concurrently, the AMS indicated enhanced levels of methane sulfonic acid (MSA) and marine-like organic aerosol (OA) correlated in time with the presence of larger particles, as well as an iodide signal which correlated with the presence of small particles. These observations suggest that iodine oxides could be one contributor to particle formation, and that marine-like OA and MSA could contribute to particle growth in the summertime Arctic.

  13. Particle number emission factors for an urban highway tunnel

    NASA Astrophysics Data System (ADS)

    Perkins, Jessica L.; Padró-Martínez, Luz T.; Durant, John L.

    2013-08-01

    Exposure to traffic-related air pollution has been linked to increased risks of cardiopulmonary disease, asthma, and reduced lung function. Ultrafine particles (UFP; aerodynamic diameter < 100 nm), one component of traffic exhaust, may contribute to these risks. This paper describes the development of UFP emission factors, an important input parameter for dispersion models used for exposure assessment. Measurements of particle number concentration (PNC), a proxy for UFP, were performed in the Central Artery Tunnel on Interstate-93 in Boston (MA, USA). The tunnel system consists of two, unidirectional bores, which each carry ˜9 × 104 vehicles per day (diesel vehicles comprise 2-5% of the fleet in the southbound tunnel and 1-3% in the northbound tunnel). A tunnel was chosen for study because it provided an enclosed environment where the effects of lateral and vertical dispersion by ambient air and photochemical reactions would be minimized. Data were collected using a mobile platform equipped with rapid-response instruments for measuring PNC (4-3000 nm) as well as NOx. Because Boston is located in a temperate region (latitude 42° N), we were interested in studying seasonal and diurnal differences in emission factors. To characterize seasonal differences, mobile monitoring was performed on 36 days spaced at 7-14 day intervals over one year (Sept. 2010-Sept. 2011); to characterize diurnal differences intensive mobile monitoring (n = 90 total trips through the tunnels) was performed over the course of two consecutive days in January 2012. All data collected during congested traffic conditions (˜7% of total data set) were removed from the analysis. The median PNC inside the two tunnels for all trips during the 12-month campaign was 3-4-fold higher than on I-93 immediately outside the tunnel and 7-10-fold higher than on I-93 4 km from the tunnel. The median particle number emission factors (EFPN) (±median absolute deviation) for the southbound and northbound tunnels

  14. Particle Acceleration, Magnetic Field Generation and Emission from Relativistic Jets

    NASA Technical Reports Server (NTRS)

    Nishikawa, K.-I.; Hardee, P.; Hededal, C.; Mizuno, Yosuke; Fishman, G. Jerry; Hartmann, D. H.

    2006-01-01

    Nonthermal radiation observed from astrophysical systems containing relativistic jets and shocks, e.g., active galactic nuclei (AGNs), gamma-ray bursts (GRBs), supernova remnants, and Galactic microquasar systems usually have power-law emission spectra. Fermi acceleration is the mechanism usually assumed for the acceleration of particles in astrophysical environments. Recent PIC simulations using injected relativistic electron-ion (electro-positron) jets show that particle acceleration occurs within the downstream jet, rather than by the scattering of particles back and forth across the shock as in Fermi acceleration. Shock acceleration' is a ubiquitous phenomenon in astrophysical plasmas. Plasma waves and their associated instabilities (e.g., the Buneman instability, other two-streaming instability, and the Weibel instability) created in the shocks are responsible for particle (electron, positron, and ion) acceleration. The simulation results show that the Weibel instability is responsible for generating and amplifying highly nonuniform, small-scale magnetic fields. These magnetic fields contribute to the electron's transverse deflection behind the jet head. The "jitter" radiation from deflected electrons has different spectral properties than synchrotron radiation which is calculated in a uniform magnetic field. This jitter radiation may be important to understanding the complex time evolution and/or spectral structure in gamma-ray bursts, relativistic jets, and supernova remnants. We will review recent PIC simulations of relativistic jets and try to make a connection with observations.

  15. Unitized Regenerative Fuel Cells for solar rechargeable aircraft and zero emission vehicles

    NASA Astrophysics Data System (ADS)

    Mitlitsky, Fred; Colella, Nicholas J.; Myers, Blake

    1994-09-01

    A unitized regenerative fuel cell (URFC) produces power and electrolytically regenerates its reactants using a single stack of reversible cells. URFC'S have been designed for high altitude long endurance (HALE) solar rechargeable aircraft (SRA), zero emission vehicles (ZEV's), hybrid energy storage/propulsion systems for long duration satellites, energy storage for remote (off-grid) power sources, and peak shaving for on-grid applications. URFC's have been considered using hydrogen/oxygen, hydrogen/air, or hydrogen/halogen chemistries. This discussion is limited to the lightweight URFC energy storage system designs for span-loaded HALE SRA using hydrogen/oxygen, and for ZEV's using hydrogen/air with oxygen supercharging. Overlapping and synergistic development and testing opportunities for these two technologies will be highlighted.

  16. The IR emission features - Emission from PAH molecules and amorphous carbon particles

    NASA Technical Reports Server (NTRS)

    Allamandola, L. J.; Tielens, A. G. G. M.; Barker, J. R.

    1987-01-01

    Techniques for the assessment of the importance of the various forms of PAHs, and recent infrared observations concerning the PAH problem, are considered. Spectroscopic data suggest that the observed interstellar spectrum is due to both free molecule-sized PAHs producing the narrow features, and amorphous carbon particles contributing to the broad underlying components. Explanations for the multicomponent emission spectrum are discussed. A model of the emission mechanism for the example of chrysene is presented, and an exact treatment of the IR fluorescence from highly vibrationally excited large molecules shows that species containing 20-30 carbon atoms are responsible for the narrow features, although the spectra more closely resemble those of amorphous carbon particles. It is suggested that future emphasis should be placed on the spatial characteristics of the component spectra.

  17. Characterizing the impact of urban emissions on regional aerosol particles; airborne measurements during the MEGAPOLI experiment

    NASA Astrophysics Data System (ADS)

    Freney, E. J.; Sellegri, K.; Canonaco, F.; Colomb, A.; Borbon, A.; Michoud, V.; Doussin, J.-F.; Crumeyrolle, S.; Amarouch, N.; Pichon, J.-M.; Prévôt, A. S. H.; Beekmann, M.; Schwarzenböeck, A.

    2013-09-01

    The MEGAPOLI experiment took place in July 2009. The aim of this campaign was to study the aging and reactions of aerosol and gas-phase emissions in the city of Paris. Three ground-based measurement sites and several mobile platforms including instrument equipped vehicles and the ATR-42 aircraft were involved. We present here the variations in particle- and gas-phase species over the city of Paris using a combination of high-time resolution measurements aboard the ATR-42 aircraft. Particle chemical composition was measured using a compact time-of-flight aerosol mass spectrometer (C-ToF-AMS) giving detailed information of the non-refractory submicron aerosol species. The mass concentration of BC, measured by a particle absorption soot photometer (PSAP), was used as a marker to identify the urban pollution plume boundaries. Aerosol mass concentrations and composition were affected by air-mass history, with air masses that spent longest time over land having highest fractions of organic aerosol and higher total mass concentrations. The Paris plume is mainly composed of organic aerosol (OA), black carbon and nitrate aerosol, as well as high concentrations of anthropogenic gas-phase species such as toluene, benzene, and NOx. Using BC and CO as tracers for air-mass dilution, we observe the ratio of ΔOA / ΔBC and ΔOA / ΔCO increase with increasing photochemical age (-log(NOx / NOy). Plotting the equivalent ratios for the Positive Matrix Factorization (PMF) resolved species (LV-OOA, SV-OOA, and HOA) illustrate that the increase in OA is a result of secondary organic aerosol (SOA). Within Paris the changes in the ΔOA / ΔCO are similar to those observed during other studies in Mexico city, Mexico and in New England, USA. Using the measured VOCs species together with recent organic aerosol formation yields we predicted ~ 50% of the measured organics. These airborne measurements during the MEGAPOLI experiment show that urban emissions contribute to the formation of OA

  18. The ir emission features: Emission from PAH (Polycyclic Aromatic Hydrocarbons) molecules and amorphous carbon particles

    SciTech Connect

    Allamandola, L.J.; Tielens, A.G.G.M.; Barker, J.R.

    1986-01-01

    PAHs can have several forms in the interstellar medium. To assess the importance of each requires the availability of a collection of high quality, complete mid-ir interstellar emission spectra, a collection of laboratory spectra of PAH samples prepared under realistic conditions and a firm understanding of the microscopic emission mechanism. Given what we currently know about PAHs, the spectroscopic data suggests that there are at least two components which contribute to the interstellar emission spectrum: free molecule sized PAHs producing the narrow features and amorphous carbon particles (which are primarily made up of an irregular ''lattice'' of PAHs) contributing to the broad underlying components. An exact treatment of the ir fluorescence from highly vibrationally excited large molecules shows that species containing between 20 and 30 carbon atoms are responsible for the narrow features, although the spectra match more closely with the spectra of amorphous carbon particles. Since little is known about the spectroscopic properties of free PAHs and PAH clusters, much laboratory work is called for in conjunction with an observational program which focuses on the spatial characteristics of the spectra. In this way the distribution and evolution of carbon from molecule to particle can be traced. 38 refs., 9 figs.

  19. Particle acceleration by stimulated emission of radiation in cylindrical waveguide

    NASA Astrophysics Data System (ADS)

    Tian, Xiu-Fang; Wu, Cong-Feng; Jia, Qi-Ka

    2015-07-01

    In particle acceleration by stimulated emission of radiation (PASER), efficient interaction occurs when a train of micro-bunches has periodicity identical to the resonance frequency of the medium. Previous theoretical calculations based on the simplified model have only considered the energy exchange in the boundless condition. Under experimental conditions, however, the gas active medium must be guided by the metal waveguide. In this paper, we have developed a model of the energy exchange between a train of micro-bunches and a gas mixture active medium in a waveguide boundary for the first time, based on the theory of electromagnetic fields, and made detailed analysis and calculations with MathCAD. The results show that energy density can be optimized to a certain value to get the maximum energy exchange. Supported by National Natural Science Foundation of China (10675116) and Major State Basic Research Development Programme of China (2011CB808301)

  20. Photoelectric charging of dust particles: Effect of spontaneous and light induced field emission of electrons

    SciTech Connect

    Sodha, M. S.; Dixit, A.

    2009-09-07

    The authors have analyzed the charging of dust particles in a plasma, taking into account the electron/ion currents to the particles, electron/ion generation and recombination, electric field emission, photoelectric emission and photoelectric field emission of electrons under the influence of light irradiation; the irradiance has been assumed to be at a level, which lets the particles retain the negative sign of the charge. Numerical results and discussion conclude the papers.

  1. Particle filtering based structural assessment with acoustic emission sensing

    NASA Astrophysics Data System (ADS)

    Yan, Wuzhao; Abdelrahman, Marwa; Zhang, Bin; Ziehl, Paul

    2017-02-01

    Nuclear structures are designed to withstand severe loading events under various stresses. Over time, aging of structural systems constructed with concrete and steel will occur. This deterioration may reduce service life of nuclear facilities and/or lead to unnecessary or untimely repairs. Therefore, online monitoring of structures in nuclear power plants and waste storage has drawn significant attention in recent years. Of many existing non-destructive evaluation and structural monitoring approaches, acoustic emission is promising for assessment of structural damage because it is non-intrusive and is sensitive to corrosion and crack growth in reinforced concrete elements. To provide a rapid, actionable, and graphical means for interpretation Intensity Analysis plots have been developed. This approach provides a means for classification of damage. Since the acoustic emission measurement is only an indirect indicator of structural damage, potentially corrupted by non-genuine data, it is more suitable to estimate the states of corrosion and cracking in a Bayesian estimation framework. In this paper, we will utilize the accelerated corrosion data from a specimen at the University of South Carolina to develop a particle filtering-based diagnosis and prognosis algorithm. Promising features of the proposed algorithm are described in terms of corrosion state estimation and prediction of degradation over time to a predefined threshold.

  2. Modeling and Detection of Ice Particle Accretion in Aircraft Engine Compression Systems

    NASA Technical Reports Server (NTRS)

    May, Ryan D.; Simon, Donald L.; Guo, Ten-Huei

    2012-01-01

    The accretion of ice particles in the core of commercial aircraft engines has been an ongoing aviation safety challenge. While no accidents have resulted from this phenomenon to date, numerous engine power loss events ranging from uneventful recoveries to forced landings have been recorded. As a first step to enabling mitigation strategies during ice accretion, a detection scheme must be developed that is capable of being implemented on board modern engines. In this paper, a simple detection scheme is developed and tested using a realistic engine simulation with approximate ice accretion models based on data from a compressor design tool. These accretion models are implemented as modified Low Pressure Compressor maps and have the capability to shift engine performance based on a specified level of ice blockage. Based on results from this model, it is possible to detect the accretion of ice in the engine core by observing shifts in the typical sensed engine outputs. Results are presented in which, for a 0.1 percent false positive rate, a true positive detection rate of 98 percent is achieved.

  3. Views of Growing Methane Emissions near Oil and Natural Gas Activity: Satellite, Aircraft, and Ground

    NASA Astrophysics Data System (ADS)

    Kollonige, D. E.; Thompson, A. M.; Diskin, G. S.; Hannigan, J. W.; Nussbaumer, E.

    2015-12-01

    To better understand the discrepancies between current top-down and bottom-up estimates, additional methane (CH4) measurements are necessary for regions surrounding growing oil and natural gas (ONG) development. We have evaluated satellite measurements of CH4 in US regions with ONG operations for their application as "top-down" constraints (part of the NASA Air Quality Applied Sciences Team (AQAST) project). For validation of the satellite instruments' sensitivities to emitted gases, we focus on regions where the DISCOVER-AQ (Deriving Information on Surface Conditions from Column and Vertically Resolved Observations Relevant to Air Quality) campaign deployed ground and aircraft measurements in Maryland (2011), California and Texas (2013), and Colorado (2014). The largest CH4 signals were observed in the Greater Green River and Powder River Basins using Tropospheric Emission Spectrometer (TES) Representative Tropospheric Volume Mixing Ratio (RTVMR) measurements. A long-term comparison between a ground remote-sensing Fourier Transform Spectrometer (FTS) at Boulder and TES for 2010-2013 shows good correlation and differences ranging 2.5-5% for their yearly distribution of total column CH4. To determine any correlation between lower/mid-tropospheric CH4 (where a thermal IR sensor, such as TES, is most sensitive) and near-surface/boundary CH4 (where sources emit), we analyze the variability of DISCOVER-AQ aircraft profiles using principal component analysis and assess the correlation between near-surface (0-2 km) and mid-tropospheric (>2 km) CH4 concentrations. Using these relationships, we estimate near-surface CH4 using mid-tropospheric satellite measurements based on the partial column amounts within vertical layers with a linear regression. From this analysis, we will demonstrate whether the uncertainties of satellite-estimated near-surface CH4 are comparable to observed variability near ONG activity. These results will assist validation of satellite instrument

  4. MONDO: a neutron tracker for particle therapy secondary emission characterisation.

    PubMed

    Marafini, M; Gasparini, L; Mirabelli, R; Pinci, D; Patera, V; Sciubba, A; Spiriti, E; Stoppa, D; Traini, G; Sarti, A

    2017-04-21

    Tumour control is performed in particle therapy using particles and ions, whose high irradiation precision enhances the effectiveness of the treatment, while sparing the healthy tissue surrounding the target volume. Dose range monitoring devices using photons and charged particles produced by the beam interacting with the patient's body have already been proposed, but no attempt has been made yet to exploit the detection of the abundant neutron component. Since neutrons can release a significant dose far away from the tumour region, precise measurements of their flux, production energy and angle distributions are eagerly sought in order to improve the treatment planning system (TPS) software. It will thus be possible to predict not only the normal tissue toxicity in the target region, but also the risk of late complications in the whole body. The aforementioned issues underline the importance of an experimental effort devoted to the precise characterisation of neutron production, aimed at the measurement of their abundance, emission point and production energy. The technical challenges posed by a neutron detector aimed at high detection efficiency and good backtracking precision are addressed within the MONDO (monitor for neutron dose in hadrontherapy) project, whose main goal is to develop a tracking detector that can target fast and ultrafast neutrons. A full reconstruction of two consecutive elastic scattering interactions undergone by the neutrons inside the detector material will be used to measure their energy and direction. The preliminary results of an MC simulation performed using the FLUKA software are presented here, together with the DSiPM (digital SiPM) readout implementation. New detector readout implementations specifically tailored to the MONDO tracker are also discussed, and the neutron detection efficiency attainable with the proposed neutron tracking strategy are reported.

  5. The IR emission features - Emission from PAH molecules and amorphous carbon particles

    NASA Technical Reports Server (NTRS)

    Allamandola, L. J.; Tielens, A. G. G. M.; Barker, J. R.

    1987-01-01

    Given the current understanding of polycyclic aromatic hydrocarbons (PAHs), the spectroscopic data suggest that are at least two components which contribute to the interstellar emission spectrum: (1) free molecule-sized PAHs producing the narrow features and (2) amorphous carbon particles (which are primarily composed of an irregular 'lattice' of PAHs) contributing to the broad underlying components. An exact treatment of the IR fluorescence from highly vibrationally excited large molecules demonstrates that species containing between 20 and 30 carbon atoms are responsible for the narrow features, although the spectra match more closely with the spectra of amorphous carbon particles. It is concluded that, since little is known about the spectroscopic properties of free PAHs and PAH clusters, much laboratory work is required along with an observational program focusing on the spatial characteristics of the spectra.

  6. Quantifying particle size and turbulent scale dependence of dust flux in the Sahara using aircraft measurements

    NASA Astrophysics Data System (ADS)

    Rosenberg, Philip D.; Parker, Douglas J.; Ryder, Claire L.; Marsham, John H.; Garcia-Carreras, Luis; Dorsey, James R.; Brooks, Ian M.; Dean, Angela R.; Crosier, Jonathon; McQuaid, James B.; Washington, Richard

    2014-06-01

    The first size-resolved airborne measurements of dust fluxes and the first dust flux measurements from the central Sahara are presented and compared with a parameterization by Kok (2011a). High-frequency measurements of dust size distribution were obtained from 0.16 to 300 µm diameter, and eddy covariance fluxes were derived. This is more than an order of magnitude larger size range than previous flux estimates. Links to surface emission are provided by analysis of particle drift velocities. Number flux is described by a -2 power law between 1 and 144 µm diameter, significantly larger than the 12 µm upper limit suggested by Kok (2011a). For small particles, the deviation from a power law varies with terrain type and the large size cutoff is correlated with atmospheric vertical turbulent kinetic energy, suggesting control by vertical transport rather than emission processes. The measured mass flux mode is in the range 30-100 µm. The turbulent scales important for dust flux are from 0.1 km to 1-10 km. The upper scale increases during the morning as boundary layer depth and eddy size increase. All locations where large dust fluxes were measured had large topographical variations. These features are often linked with highly erodible surface features, such as wadis or dunes. We also hypothesize that upslope flow and flow separation over such features enhance the dust flux by transporting large particles out of the saltation layer. The tendency to locate surface flux measurements in open, flat terrain means these favored dust sources have been neglected in previous studies.

  7. Net in-cabin emission rates of VOCs and contributions from outside and inside the aircraft cabin

    NASA Astrophysics Data System (ADS)

    Guan, Jun; Li, Zheng; Yang, Xudong

    2015-06-01

    Volatile organic compounds (VOCs) are one of the most important types of air pollutants in aircraft cabin. Balancing source intensity of VOCs and ventilation strategies is an essential conducive way to obtain acceptable aircraft cabin environment. This paper intends to develop a simplified model by a case study to estimate the net VOC emission rates of cabin interior, and contributions from outside and inside the aircraft cabin. In-flight continuous measurements of total VOCs (TVOC) in cabin air were made in six domestic flights in March 2013. The results indicate that the concentrations of TVOC mostly ranged from 0.20 mg m-3 to 0.40 mg m-3 in cabin air, which first increased at ascent, and then kept elevated during cruise, and decreased at descent in general. For further ventilation information, carbon dioxide (CO2) in supply air and re-circulated air was simultaneously observed as a ventilation tracer to calculate the bleed air ratios, outside airflow rates and total airflow rates in these flights. And thus, the emission rates derived from cabin interior and contributions of TVOC from bleed air and cabin interior were estimated for the whole flight accordingly. Results indicate that during the cruise phase, TVOC in cabin air mainly came from cabin interiors. However, contributions from outside air also became significant during taxiing on the ground, ascent and descent phases. The simplified model would be useful for developing better control strategies of aircraft cabin air quality.

  8. Improving and Assessing Aircraft-based Greenhouse Gas Emission Rate Measurements at Indianapolis as part of the INFLUX project.

    NASA Astrophysics Data System (ADS)

    Heimburger, A. M. F.; Shepson, P. B.; Stirm, B. H.; Susdorf, C.; Cambaliza, M. O. L.

    2015-12-01

    Since the Copenhagen accord in 2009, several countries have affirmed their commitment to reduce their greenhouse gas emissions. The United States and Canada committed to reduce their emissions by 17% below 2005 levels, by 2020, Europe by 14% and China by ~40%. To achieve such targets, coherent and effective strategies in mitigating atmospheric carbon emissions must be implemented in the next decades. Whether such goals are actually achieved, they require that reductions are "measurable", "reportable", and "verifiable". Management of greenhouse gas emissions must focus on urban environments since ~74% of CO2 emissions worldwide will be from cities, while measurement approaches are highly uncertain (~50% to >100%). The Indianapolis Flux Experiment (INFLUX) was established to develop, assess and improve top-down and bottom-up quantifications of urban greenhouse gas emissions. Based on an aircraft mass balance approach, we performed a series of experiments focused on the improvement of CO2, CH4 and CO emission rates quantification from Indianapolis, our final objective being to drastically improve the method overall uncertainty from the previous estimate of 50%. In November-December 2014, we conducted nine methodologically identical mass balance experiments in a short period of time (24 days, one downwind distance) for assumed constant total emission rate conditions, as a means to obtain an improved standard deviation of the mean determination. By averaging the individual emission rate determinations, we were able to obtain a method precision of 17% and 16% for CO2 and CO, respectively, at the 95%C.L. CH4 emission rates are highly variable day to day, leading to precision of 60%. Our results show that repetitive sampling can enable improvement in precision of the aircraft top-down methods through averaging.

  9. Vertical velocities within a Cirrus cloud from Doppler lidar and aircraft measurements during FIRE: Implications for particle growth

    NASA Technical Reports Server (NTRS)

    Gultepe, Ismail; Heymsfield, Andrew J.

    1990-01-01

    A large and comprehensive data set taken by the NOAA CO2 Doppler lidar, the NCAR King Air, and rawinsondes on 31 October 1986 during the FIRE (First ISCCP Regional Experiment) field program which took place in Wisconsin are presented. Vertical velocities are determined from the Doppler lidar data, and are compared with velocities derived from the aircraft microphysical data. The data are used for discussion of particle growth and dynamical processes operative within the cloud.

  10. Aircraft Emission Inventories Projected in Year 2015 for a High Speed Civil Transport (HSCT) Universal Airline Network

    NASA Technical Reports Server (NTRS)

    Baughcum, Steven L.; Henderson, Stephen C.

    1995-01-01

    This report describes the development of a three-dimensional database of aircraft fuel burn and emissions (fuel burned, NOx, CO, and hydrocarbons) from projected fleets of high speed civil transports (HSCT's) on a universal airline network.Inventories for 500 and 1000 HSCT fleets, as well as the concurrent subsonic fleets, were calculated. The objective of this work was to evaluate the changes in geographical distribution of the HSCT emissions as the fleet size grew from 500 to 1000 HSCT's. For this work, a new expanded HSCT network was used and flights projected using a market penetration analysis rather than assuming equal penetration as was done in the earlier studies. Emission inventories on this network were calculated for both Mach 2.0 and Mach 2.4 HSCT fleets with NOx cruise emission indices of approximately 5 and 15 grams NOx/kg fuel. These emissions inventories are available for use by atmospheric scientists conducting the Atmospheric Effects of Stratospheric Aircraft (AESA) modeling studies. Fuel burned and emissions of nitrogen oxides (NOx as NO2), carbon monoxide, and hydrocarbons have been calculated on a 1 degree latitude x 1 degree longitude x 1 kilometer attitude grid and delivered to NASA as electronic files.

  11. Characterization of dust emission from alluvial sediments using aircraft observations and modeling

    NASA Astrophysics Data System (ADS)

    Schepanski, K.; Flamant, C.; Chaboureau, J.; Kocha, C.; Banks, J.; Brindley, H. E.; Lavaysse, C.; Marnas, F.; Pelon, J.; Tulet, P.

    2013-12-01

    Recent studies using satellite observations show that numerous dust sources are located in the foothills of arid and semi-arid mountain regions such as over North Africa. Alluvial sediments deposited on the valley bottoms and flood plains are very prone to wind erosion and frequently serve as dust source. High surface wind speeds related to the break-down of the nocturnal low-level jet (LLJ) during the morning hours are identified as a frequent driving mechanism for dust uplift. We investigate dust emission from alluvial dust sources located within the upland region in northern Mauritania and discuss the impact of valleys with regard to their role as dust source. Measures for local atmospheric dust burden were retrieved from airborne observations, MSG SEVIR dust AOD fields and MesoNH model simulations, and analyzed in order to provide complementary information on dust source activation and local dust transport at different horizontal scales. Vertical distribution of atmospheric mineral dust was obtained from the LNG backscatter lidar system flying aboard the French Falcon-20 aircraft. Lidar extinction coefficients were compared to topography, aerial photographs, and dust AOD fields to confirm the relevance of alluvial sediments at the valley bottoms as dust source. The observed dust emission event was further evaluated using the regional model MesoNH. A sensitivity study on the impact of the horizontal grid spacing highlights the importance of the spatial resolution on simulated dust loadings. The results further illustrate the importance of an explicit representation of alluvial dust sources in such models to better capture the spatial-temporal distribution of airborne dust concentrations.

  12. Characterization of dust emission from alluvial sources using aircraft observations and high-resolution modeling

    NASA Astrophysics Data System (ADS)

    Schepanski, Kerstin; Flamant, Cyrille; Chaboureau, Jean-Pierre; Kocha, Cecile; Banks, Jamie; Brindley, Helen; Lavaysse, Christophe; Marnas, Fabien; Pelon, Jacques; Tulet, Pierre

    2013-04-01

    We investigate mineral dust emission from alluvial sediments within the upland region in northern Mauritania in the vicinity of a decaying nocturnal low-level jet (LLJ). For the first time, the impact of valleys that are embedded in a rather homogeneous surrounding is investigated with regard to their role as dust source. Measures for local atmospheric dust burden were retrieved from airborne observations, satellite observations, and model simulations and analyzed in order to provide complementary information at different horizontal scales. Observations by the LNG backscatter lidar system flying aboard the SAFIRE Falcon 20 aircraft were taken along five parallel flight legs perpendicular to the orientation of the main valley system dominating the topography of the study area. Results from a comparison of lidar-derived extinction coefficients with topography and aerial photographs confirm the relevance of (1) alluvial sediments at the valley bottoms as a dust source, and (2) the break-down of the nocturnal LLJ as a trigger for dust emission in this region. An evaluation of the AROME regional model, forecasting dust at high resolution (5 km grid), points towards an underrepresentation of alluvial dust sources in this region. This is also evident from simulations by the MesoNH research model. Although MesoNH simulations show higher dust loadings than AROME which are more comparable to the observations, both models understimate the dust concentrations within the boundary layer compared to lidar observations. A sensitivity study on the impact of horizontal grid spacing (5 km versus 1 km) highlights the importance of spatial resolution on simulated dust loadings.

  13. Vacuum cleaner emissions as a source of indoor exposure to airborne particles and bacteria.

    PubMed

    Knibbs, Luke D; He, Congrong; Duchaine, Caroline; Morawska, Lidia

    2012-01-03

    Vacuuming can be a source of indoor exposure to biological and nonbiological aerosols, although there are few data that describe the magnitude of emissions from the vacuum cleaner itself. We therefore sought to quantify emission rates of particles and bacteria from a large group of vacuum cleaners and investigate their potential determinants, including temperature, dust bags, exhaust filters, price, and age. Emissions of particles between 0.009 and 20 μm and bacteria were measured from 21 vacuums. Ultrafine (<100 nm) particle emission rates ranged from 4.0 × 10(6) to 1.1 × 10(11) particles min(-1). Emission of 0.54-20 μm particles ranged from 4.0 × 10(4) to 1.2 × 10(9) particles min(-1). PM(2.5) emissions were between 2.4 × 10(-1) and 5.4 × 10(3) μg min(-1). Bacteria emissions ranged from 0 to 7.4 × 10(5) bacteria min(-1) and were poorly correlated with dust bag bacteria content and particle emissions. Large variability in emission of all parameters was observed across the 21 vacuums, which was largely not attributable to the range of determinant factors we assessed. Vacuum cleaner emissions contribute to indoor exposure to nonbiological and biological aerosols when vacuuming, and this may vary markedly depending on the vacuum used.

  14. Source apportionment of airborne particles in commercial aircraft cabin environment: Contributions from outside and inside of cabin

    NASA Astrophysics Data System (ADS)

    Li, Zheng; Guan, Jun; Yang, Xudong; Lin, Chao-Hsin

    2014-06-01

    Airborne particles are an important type of air pollutants in aircraft cabin. Finding sources of particles is conducive to taking appropriate measures to remove them. In this study, measurements of concentration and size distribution of particles larger than 0.3 μm (PM>0.3) were made on nine short haul flights from September 2012 to March 2013. Particle counts in supply air and breathing zone air were both obtained. Results indicate that the number concentrations of particles ranged from 3.6 × 102 counts L-1 to 1.2 × 105 counts L-1 in supply air and breathing zone air, and they first decreased and then increased in general during the flight duration. Peaks of particle concentration were found at climbing, descending, and cruising phases in several flights. Percentages of particle concentration in breathing zone contributed by the bleed air (originated from outside) and cabin interior sources were calculated. The bleed air ratios, outside airflow rates and total airflow rates were calculated by using carbon dioxide as a ventilation tracer in five of the nine flights. The calculated results indicate that PM>0.3 in breathing zone mainly came from unfiltered bleed air, especially for particle sizes from 0.3 to 2.0 μm. And for particles larger than 2.0 μm, contributions from the bleed air and cabin interior were both important. The results would be useful for developing better cabin air quality control strategies.

  15. Time-resolved characterization of primary and secondary particle emissions of a modern gasoline passenger car

    NASA Astrophysics Data System (ADS)

    Karjalainen, P.; Timonen, H.; Saukko, E.; Kuuluvainen, H.; Saarikoski, S.; Aakko-Saksa, P.; Murtonen, T.; Dal Maso, M.; Ahlberg, E.; Svenningsson, B.; Brune, W. H.; Hillamo, R.; Keskinen, J.; Rönkkö, T.

    2015-11-01

    Changes in traffic systems and vehicle emission reduction technologies significantly affect traffic-related emissions in urban areas. In many densely populated areas the amount of traffic is increasing, keeping the emission level high or even increasing. To understand the health effects of traffic related emissions, both primary and secondary particles that are formed in the atmosphere from gaseous exhaust emissions need to be characterized. In this study we used a comprehensive set of measurements to characterize both primary and secondary particulate emissions of a modern gasoline passenger car. Our aerosol particle study covers the whole process chain in emission formation, from the engine to the atmosphere, and takes into account also differences in driving patterns. We observed that in mass terms, the amount of secondary particles was 13 times higher than the amount of primary particles. The formation, composition, number, and mass of secondary particles was significantly affected by driving patterns and engine conditions. The highest gaseous and particulate emissions were observed at the beginning of the test cycle when the performance of the engine and the catalyst was below optimal. The key parameter for secondary particle formation was the amount of gaseous hydrocarbons in primary emissions; however, also the primary particle population had an influence. Thus, in order to enhance human health and wellbeing in urban areas, our study strongly indicates that in future legislation, special attention should be directed into the reduction of gaseous hydrocarbons.

  16. Experimental Evidence for Particle Acceleration by Stimulated Emission of Radiation

    SciTech Connect

    Banna, Samer; Berezovsky, Valery; Schaechter, Levi

    2006-11-27

    The interaction of electromagnetic radiation with free electrons in the presence of an active medium has several appealing outcomes. Among them the PASER scheme, standing for Particle Acceleration by Stimulated Emission of Radiation. In the framework of this scheme, energy stored in an active medium (microscopic cavities) is transferred directly to an e-beam traversing the medium, and therefore, accelerating the former. Recently, a proof-of-principle experiment of this concept was performed at the Brookhaven National Laboratory reaching a gain of 200keV in the kinetic energy of a 5ps, 0.1nc and 45MeV quasi-mono-energetic macro-bunch which is modulated by its interaction with a CO2 laser pulse in an adequate wiggler. In the framework of this proof-of-principle experiment both the fundamental frequency of the train of micro-bunches and the medium's resonance frequency (CO2 mixture) are matched. A good agreement is found between the energy gain and a 2D analytic model that has been developed.

  17. Impact of aircraft NOx emissions on tropospheric ozone calculated with a chemistry-general circulation model: Sensitivity to higher hydrocarbon chemistry

    NASA Astrophysics Data System (ADS)

    Kentarchos, A. S.; Roelofs, G. J.

    2002-07-01

    A three-dimensional chemistry-general circulation model has been employed to estimate the impact of current aircraft NOx emissions on tropospheric ozone. The model contains a representation of higher hydrocarbon chemistry, implemented by means of the Carbon Bond Mechanism 4 (CBM4), in order to investigate the potential effect of higher hydrocarbons on aircraft-induced ozone changes. Aircraft NOx emissions increase background NOX (= NO + NO2 + NO3 + 2N2O5 + HNO4) concentrations by 50-70 pptv in the upper troposphere over the Northern Hemisphere, and contribute up to 3 ppbv to upper tropospheric background ozone levels. When higher hydrocarbon chemistry is considered in the simulation, the aircraft-induced ozone perturbations are higher by ~12% during summer and the aircraft-induced ozone production efficiency per NOx molecule increases by ~20%, when compared to a simulation without higher hydrocarbon chemistry.

  18. Ship emissions measurement in the Arctic by plume intercepts of the Canadian Coast Guard icebreaker Amundsen from the Polar 6 aircraft platform

    NASA Astrophysics Data System (ADS)

    Aliabadi, Amir A.; Thomas, Jennie L.; Herber, Andreas B.; Staebler, Ralf M.; Leaitch, W. Richard; Schulz, Hannes; Law, Kathy S.; Marelle, Louis; Burkart, Julia; Willis, Megan D.; Bozem, Heiko; Hoor, Peter M.; Köllner, Franziska; Schneider, Johannes; Levasseur, Maurice; Abbatt, Jonathan P. D.

    2016-06-01

    Decreasing sea ice and increasing marine navigability in northern latitudes have changed Arctic ship traffic patterns in recent years and are predicted to increase annual ship traffic in the Arctic in the future. Development of effective regulations to manage environmental impacts of shipping requires an understanding of ship emissions and atmospheric processing in the Arctic environment. As part of the summer 2014 NETCARE (Network on Climate and Aerosols) campaign, the plume dispersion and gas and particle emission factors of effluents originating from the Canadian Coast Guard icebreaker Amundsen operating near Resolute Bay, NU, Canada, were investigated. The Amundsen burned distillate fuel with 1.5 wt % sulfur. Emissions were studied via plume intercepts using the Polar 6 aircraft measurements, an analytical plume dispersion model, and using the FLEXPART-WRF Lagrangian particle dispersion model. The first plume intercept by the research aircraft was carried out on 19 July 2014 during the operation of the Amundsen in the open water. The second and third plume intercepts were carried out on 20 and 21 July 2014 when the Amundsen had reached the ice edge and operated under ice-breaking conditions. Typical of Arctic marine navigation, the engine load was low compared to cruising conditions for all of the plume intercepts. The measured species included mixing ratios of CO2, NOx, CO, SO2, particle number concentration (CN), refractory black carbon (rBC), and cloud condensation nuclei (CCN). The results were compared to similar experimental studies in mid-latitudes. Plume expansion rates (γ) were calculated using the analytical model and found to be γ = 0.75 ± 0.81, 0.93 ± 0.37, and 1.19 ± 0.39 for plumes 1, 2, and 3, respectively. These rates were smaller than prior studies conducted at mid-latitudes, likely due to polar boundary layer dynamics, including reduced turbulent mixing compared to mid-latitudes. All emission factors were in agreement with prior

  19. The LIULIN-3M Radiometer for Measuring Particle Doses in Space and on Aircraft

    NASA Technical Reports Server (NTRS)

    Stassinopoulos, E. G.; Stauffer, C. A.; Dachev, T. P.; Brucker, G. J.; Tomov, B. T.; Dimitrov, P. G.

    1999-01-01

    This paper reports on the development of a compact radiation monitor/dosimeter, the LIULIN-3M, and on extended measurements conducted on the ground and on commercial aircraft on domestic and international flights.

  20. The LIULIN-3M Radiometer for Measuring Particle Doses in Space and on Aircraft

    NASA Technical Reports Server (NTRS)

    Stassinopoulos, E. G.; Stauffer, C. A.; Dachev, T. P.; Tomov, B. T.; Dimitrov, P. G.; Brucker, G. J.; Obenschain, Art (Technical Monitor)

    2002-01-01

    This paper reports on the development of a compact radiation monitor/dosimeter, the LIULIN-3M, and on extended measurements conducted on the ground and on commercial aircraft on domestic and international flights.

  1. Radiation Force Caused by Scattering, Absorption, and Emission of Light by Nonspherical Particles

    NASA Technical Reports Server (NTRS)

    Mishchenko, Michael I.; Hansen, James E. (Technical Monitor)

    2001-01-01

    General formulas for computing the radiation force exerted on arbitrarily oriented and arbitrarily shaped nonspherical particles due to scattering, absorption, and emission of electromagnetic radiation are derived. For randomly oriented particles with a plane of symmetry, the formula for the average radiation force caused by the particle response to external illumination reduces to the standard Debye formula derived from the Lorenz-Mie theory, whereas the average radiation force caused by emission vanishes.

  2. PARTICLE SPECIATION AND EMISSION PROFILES OF SMALL 2-STROKE ENGINES

    EPA Science Inventory

    The Human Exposure and Atmospheric Sciences Division (HEASD) conducts studies designed to acquire information from emission sources for use in source apportionment studies. The objective of this work is to characterize a complete, speciated emission profile (PM and air toxics) ...

  3. Characterization of acoustic emissions resulting from particle collision with a stationary bubble.

    PubMed

    Zhang, Wen; Spencer, Steven J; Coghill, Peter

    2013-05-01

    The present work characterizes the acoustic emissions resulting from the collision of a particle driven under gravity with a captive bubble. Conventional methods to investigate the bubble particle collision interaction model measure a descriptive parameter known as the collision time. During such a collision, particle impact may cause a strong deformation and a following oscillation of the bubble-particle interface generates detectable passive acoustic emissions (AE). Experiments and models presented show that the AE frequency monotonically decreases with the particle radius and is independent of the impact velocity, whereas the AE amplitude has a more complicated relationship with impact parameters.

  4. Impact of aircraft emissions within the boundary layer on the regional ozone concentration in South Korea using high resolution numerical models

    NASA Astrophysics Data System (ADS)

    Song, S.; Shon, Z.; Kang, Y.; Kim, Y.; Yoo, S.

    2013-12-01

    Abstract The influence of aircraft emissions within the boundary layer near the international airports in South Korea on the regional ozone (O3) concentrations were evaluated using a high resolution numerical modeling approach during summer season (August). This analysis was performed by two sets of simulation experiments: (1) with aircraft emissions (i.e. TOTAL case) and (2) without aircraft emissions (i.e. BASE case). In this study, the NOx to VOC emission ratio (NOx/VOC ratio) estimated from the aircraft ranged from approximately 4 to 11.6, which was significantly more than the ratio (approximately 1.3) of domain-wide emissions. Therefore, changes in the O3 concentration in and around the study area are likely to be primarily influenced by significantly high NOx emissions. The model study suggests the possibility that aircraft emissions near the airports can have a direct impact on the O3 concentrations in the source regions as well as their surrounding/downwind regions, depending on the sensitivity of O3 to its precursors (e.g. NOx and VOCs) and/or meteorological conditions. The contributions of physical and chemical processes to the production or loss of O3 are also assessed using a process analysis (PA) method. Acknowledgments This research was supported by Basic Science Research Program through the National Research Foundation of Korea (NRF) funded by the Ministry of Education, Science and Technology (2013-0789).

  5. Active Combustion Control for Aircraft Gas-Turbine Engines-Experimental Results for an Advanced, Low-Emissions Combustor Prototype

    NASA Technical Reports Server (NTRS)

    DeLaat, John C.; Kopasakis, George; Saus, Joseph R.; Chang, Clarence T.; Wey, Changlie

    2012-01-01

    Lean combustion concepts for aircraft engine combustors are prone to combustion instabilities. Mitigation of instabilities is an enabling technology for these low-emissions combustors. NASA Glenn Research Center s prior activity has demonstrated active control to suppress a high-frequency combustion instability in a combustor rig designed to emulate an actual aircraft engine instability experience with a conventional, rich-front-end combustor. The current effort is developing further understanding of the problem specifically as applied to future lean-burning, very low-emissions combustors. A prototype advanced, low-emissions aircraft engine combustor with a combustion instability has been identified and previous work has characterized the dynamic behavior of that combustor prototype. The combustor exhibits thermoacoustic instabilities that are related to increasing fuel flow and that potentially prevent full-power operation. A simplified, non-linear oscillator model and a more physics-based sectored 1-D dynamic model have been developed to capture the combustor prototype s instability behavior. Utilizing these models, the NASA Adaptive Sliding Phasor Average Control (ASPAC) instability control method has been updated for the low-emissions combustor prototype. Active combustion instability suppression using the ASPAC control method has been demonstrated experimentally with this combustor prototype in a NASA combustion test cell operating at engine pressures, temperatures, and flows. A high-frequency fuel valve was utilized to perturb the combustor fuel flow. Successful instability suppression was shown using a dynamic pressure sensor in the combustor for controller feedback. Instability control was also shown with a pressure feedback sensor in the lower temperature region upstream of the combustor. It was also demonstrated that the controller can prevent the instability from occurring while combustor operation was transitioning from a stable, low-power condition to

  6. Emissions of Trace Gases and Particles from Two Ships in the Southern Atlantic Ocean

    NASA Technical Reports Server (NTRS)

    Sinha, Parikhit; Hobbs, Peter V.; Yokelson, Robert J.; Christian, Ted J.; Kirchstetter, Thomas W.; Bruintjes, Roelof

    2003-01-01

    Measurements were made of the emissions of particles and gases from two diesel-powered ships in the southern Atlantic Ocean off the coast of Namibia. The measurements are used to derive emission factors from ships of three species not reported previously, namely, black carbon, accumulation-mode particles, and cloud condensation nuclei (CCN), as well as for carbon dioxide, carbon monoxide (CO), methane (CH4), non-methane hydrocarbons, sulfur dioxide (SO2), nitrogen oxides (NOx), and condensation nuclei. The effects of fuel grade and engine power on ship emissions are discussed. The emission factors are combined with fuel usage data to obtain estimates of global annual emissions of various particles and gases from ocean-going ships. Global emissions of black carbon, accumulation- mode particles, and CCN from ocean-going ships are estimated to be 19-26 Gg yr(sup -1), (4.4-6.1) x 10(exp 26) particles yr(sup -1), and (1.0-1.5) x l0(exp 26) particles yr(sup -1), respectively. Black carbon emissions from ocean-going ships are approximately 0.2% of total anthropogenic emissions. Emissions of NOx and SO2 from ocean-going ships are approximately 10-14% and approximately 3-4%, respectively, of the total emissions of these species from the burning of fossil fuels, and approximately 40% and approximately 70%, respectively, of the total emissions of these species from the burning of biomass. Global annual emissions of CO and CH4 from ocean-going ships are approximately 2% and approximately 2-5%, respectively, of natural oceanic emissions of these species.

  7. Determining size-specific emission factors for environmental tobacco smoke particles

    SciTech Connect

    Klepeis, Neil E.; Apte, Michael G.; Gundel, Lara A.; Sextro, Richard G.; Nazaroff, William W.

    2002-07-07

    Because size is a major controlling factor for indoor airborne particle behavior, human particle exposure assessments will benefit from improved knowledge of size-specific particle emissions. We report a method of inferring size-specific mass emission factors for indoor sources that makes use of an indoor aerosol dynamics model, measured particle concentration time series data, and an optimization routine. This approach provides--in addition to estimates of the emissions size distribution and integrated emission factors--estimates of deposition rate, an enhanced understanding of particle dynamics, and information about model performance. We applied the method to size-specific environmental tobacco smoke (ETS) particle concentrations measured every minute with an 8-channel optical particle counter (PMS-LASAIR; 0.1-2+ micrometer diameters) and every 10 or 30 min with a 34-channel differential mobility particle sizer (TSI-DMPS; 0.01-1+ micrometer diameters) after a single cigarette or cigar was machine-smoked inside a low air-exchange-rate 20 m{sup 3} chamber. The aerosol dynamics model provided good fits to observed concentrations when using optimized values of mass emission rate and deposition rate for each particle size range as input. Small discrepancies observed in the first 1-2 hours after smoking are likely due to the effect of particle evaporation, a process neglected by the model. Size-specific ETS particle emission factors were fit with log-normal distributions, yielding an average mass median diameter of 0.2 micrometers and an average geometric standard deviation of 2.3 with no systematic differences between cigars and cigarettes. The equivalent total particle emission rate, obtained integrating each size distribution, was 0.2-0.7 mg/min for cigars and 0.7-0.9 mg/min for cigarettes.

  8. Effect of Steam Addition on the Flow Field and NOx Emissions for Jet-A in an Aircraft Combustor

    NASA Astrophysics Data System (ADS)

    Xue, Rui; Hu, Chunbo; Nikolaidis, Theoklis; Pilidis, Pericle

    2016-12-01

    The steam injection technology for aircraft engines is gaining rising importance because of the strong limitations imposed by the legislation for NOx reduction in airports. In order to investigate the impact of steam addition on combustion and NOx emissions, an integrated performance-CFD-chemical reactor network (CRN) methodology was developed. The CFD results showed steam addition reduced the high temperature size and the radical pool moved downstream. Then different post-processing techniques are employed and CRN is generated to predict NOx emissions. This network consists of 14 chemical reactor elements and the results were in close agreement with the ICAO databank. The established CRN model was then used for steam addition study and the results showed under air/steam mixture atmosphere, high steam content could push the NOx formation region to the post-flame zone and a large amount of the NOx emission could be reduced when the steam mass fraction is quite high.

  9. Aircraft HO sub x and NO sub x emission effects on stratospheric ozone and temperature

    NASA Technical Reports Server (NTRS)

    Glatt, L.; Widhopf, G. F.

    1978-01-01

    A simplified two-dimensional steady-state photochemical model of the atmosphere was developed. The model was used to study the effect on the thermal and chemical structure of the atmosphere of two types of pollution cases: (1) injection of NOx and HOx from a hypothetical fleet of supersonic and subsonic aircraft and (2) injection of HOx from a hypothetical fleet of liquid-fueled hydrogen aircraft. The results are discussed with regard to stratospheric perturbations in ozone, water vapor and temperature.

  10. Functionalization of emissive conjugated polymer nanoparticles by coprecipitation: consequences for particle photophysics and colloidal properties

    NASA Astrophysics Data System (ADS)

    Singh, Amita; Bezuidenhout, Michael; Walsh, Nichola; Beirne, Jason; Felletti, Riccardo; Wang, Suxiao; Fitzgerald, Kathleen T.; Gallagher, William M.; Kiely, Patrick; Redmond, Gareth

    2016-07-01

    The functionalization of polyfluorene (PFO) nanoparticles by coprecipitation of the conjugated polymer with an amphiphilic comb polymer, consisting of a hydrophobic polystyrene backbone with hydrophilic, carboxylic acid-terminated polyethylene oxide side-chains (PS-PEG-COOH), is investigated. The comb polymer affects the properties of the formed hybrid nanoparticles. Non-functionalized particles are typically larger (28 nm) than functionalized ones (20 nm); peak molar extinction coefficients are found to differ in a similar trend. Zeta potentials are negative, consistent with negative surface charge on PFO particles due to chemical defect formation, with additional charge on functionalized particles due to the pendant carboxylic acid groups. Emission quantum yields of functionalized particles are typically larger, consistent with lower efficiency of energy transfer to quenchers in smaller particles and weaker PFO interchain interactions due to chain dilution. The trend in per-particle fluorescence brightness values, as confirmed by single particle fluorescence imaging, reflects the nanoparticle extinction coefficients. Photostability studies on aqueous dispersions of hybrid particles indicate mild photobrightening under continuous illumination while PFO particles exhibit slow exponential emission decay. Functionalized particles are also resistant to aggregation during exposure to adenocarcinoma cells. Generally, the hybrid particles exhibit more favorable time-, pH- and medium-dependent stabilities, likely due to steric and electrostatic stabilization by PEG-carboxylic acid functionalities. Overall, the functionalized particles exhibit attractive properties: Reasonably small size, tight size distribution, high absorption cross section, radiative rate and emission quantum yield, excellent brightness and photostability, and good colloidal stability.

  11. Aircraft observations and model simulations of concentration and particle size distribution in the Eyjafjallajökull volcanic ash cloud

    NASA Astrophysics Data System (ADS)

    Dacre, H. F.; Grant, A. L. M.; Johnson, B. T.

    2013-02-01

    The Eyjafjallajökull volcano in Iceland emitted a cloud of ash into the atmosphere during April and May 2010. Over the UK the ash cloud was observed by the FAAM BAe-146 Atmospheric Research Aircraft which was equipped with in-situ probes measuring the concentration of volcanic ash carried by particles of varying sizes. The UK Met Office Numerical Atmospheric-dispersion Modelling Environment (NAME) has been used to simulate the evolution of the ash cloud emitted by the Eyjafjallajökull volcano during the period 4-18 May 2010. In the NAME simulations the processes controlling the evolution of the concentration and particle size distribution include sedimentation and deposition of particles, horizontal dispersion and vertical wind shear. For travel times between 24 and 72 h, a 1/t relationship describes the evolution of the concentration at the centre of the ash cloud and the particle size distribution remains fairly constant. Although NAME does not represent the effects of microphysical processes, it can capture the observed decrease in concentration with travel time in this period. This suggests that, for this eruption, microphysical processes play a small role in determining the evolution of the distal ash cloud. Quantitative comparison with observations shows that NAME can simulate the observed column-integrated mass if around 4% of the total emitted mass is assumed to be transported as far as the UK by small particles (< 30 μm diameter). NAME can also simulate the observed particle size distribution if a distal particle size distribution that contains a large fraction of < 10 μm diameter particles is used, consistent with the idea that phraetomagmatic volcanoes, such as Eyjafjallajökull, emit very fine particles.

  12. Aircraft observations and model simulations of concentration and particle size distribution in the Eyjafjallajökull volcanic ash cloud

    NASA Astrophysics Data System (ADS)

    Dacre, H. F.; Grant, A. L. M.; Johnson, B. T.

    2012-09-01

    The Eyjafjallajökull volcano in Iceland emitted a cloud of ash into the atmosphere during April and May 2010. Over the UK the ash cloud was observed by the FAAM BAe-146 Atmospheric Research Aircraft which was equipped with in-situ probes measuring the concentration of volcanic ash carried by particles of varying sizes. The UK Met Office Numerical Atmospheric-dispersion Modelling Environment (NAME) has been used to simulate the evolution of the ash cloud emitted by the Eyjafjallajökull volcano during the period 4-18 May 2010. In the NAME simulations the processes controlling the evolution of the concentration and particle size distribution include sedimentation and deposition of particles, horizontal dispersion and vertical wind shear. For travel times between 24 and 72 h a 1/t relationship describes the evolution of the concentration at the centre of the ash cloud and the particle size distribution remains fairly constant. Although NAME does not represent the effects of microphysical processes it can capture the observed decrease in concentration with travel time in this period. This suggests that, for this eruption, microphysical processes play a small role in determining the evolution of the distal ash cloud. Quantitative comparison with observations shows that NAME can simulate the observed column integrated mass if around 4% of the total emitted mass is assumed to be transported as far as the UK by small (<30 m diameter) particles. NAME can also simulate the observed particle size distribution if a distal particle size distribution that contains a large fraction of <10 m diameter particles is used, consistent with the idea that phraetomagmatic volcanoes, such as Eyjafjallajökull, emit very fine particles.

  13. Typical Household Vacuum Cleaners: The Collection Efficiency and Emissions Characteristics for Fine Particles.

    PubMed

    Lioy, Paul J; Wainman, Thomas; Zhang, Junfeng Jim; Goldsmith, Susan

    1999-02-01

    The issue of fine particle (PM25) exposures and their potential health effects is a focus of scientific research because of the recently promulgated National Ambient Air Quality Standard for PM2 5. Before final implementation, the health and exposure basis for the standard will be reviewed by the U.S. Environmental Protection Agency within the next five years. As part of this process, it is necessary to understand total particle exposure issues and to determine the relative importance of the origin of PM2 5 exposure in various micro-environments. The results presented in this study examine emissions of fine particles from a previously uncharacterized indoor source: the residential vacuum cleaner. Eleven standard vacuum cleaners were tested for the emission rate of fine particles by their individual motors and for their efficiency in collecting laboratory-generated fine particles. An aerosol generator was used to introduce fine potassium chloride (KC1) particles into the vacuum cleaner inlet for the collection efficiency tests. Measurements of the motor emissions, which include carbon, and the KCl aerosol were made using a continuous HIAC/Royco 5130A light-scattering particle detector. All tests were conducted in a metal chamber specifically designed to completely contain the vacuum cleaner and operate it in a stationary position. For the tested vacuum cleaners, fine particle motor emissions ranged from 9.6 x 10(4) to 3.34 x 10(8) particles/min, which were estimated to be 0.028 to 176 mg/min for mass emissions, respectively. The vast majority of particles released were in the range of 0.3-0.5 mm in diameter. The lowest particle emission rate was obtained for a vacuum cleaner that had a high efficiency (HEPA) filter placed after the vacuum cleaner bag and the motor within a sealed exhaust system. This vacuum cleaner removed the KC1particles that escaped the vacuum cleaner bag and the particles emitted by the motor. Results obtained for the KC1 collection efficiency

  14. Typical household vacuum cleaners: the collection efficiency and emissions characteristics for fine particles.

    PubMed

    Lioy, P J; Wainman, T; Zhang, J; Goldsmith, S

    1999-02-01

    The issue of fine particle (PM2.5) exposures and their potential health effects is a focus of scientific research because of the recently promulgated National Ambient Air Quality Standard for PM2.5. Before final implementation, the health and exposure basis for the standard will be reviewed by the U.S. Environmental Protection Agency within the next five years. As part of this process, it is necessary to understand total particle exposure issues and to determine the relative importance of the origin of PM2.5 exposure in various micro-environments. The results presented in this study examine emissions of fine particles from a previously uncharacterized indoor source: the residential vacuum cleaner. Eleven standard vacuum cleaners were tested for the emission rate of fine particles by their individual motors and for their efficiency in collecting laboratory-generated fine particles. An aerosol generator was used to introduce fine potassium chloride (KCl) particles into the vacuum cleaner inlet for the collection efficiency tests. Measurements of the motor emissions, which include carbon, and the KCl aerosol were made using a continuous HIAC/Royco 5130 A light-scattering particle detector. All tests were conducted in a metal chamber specifically designed to completely contain the vacuum cleaner and operate it in a stationary position. For the tested vacuum cleaners, fine particle motor emissions ranged from 9.6 x 10(4) to 3.34 x 10(8) particles/min, which were estimated to be 0.028 to 176 micrograms/min for mass emissions, respectively. The vast majority of particles released were in the range of 0.3-0.5 micron in diameter. The lowest particle emission rate was obtained for a vacuum cleaner that had a high efficiency (HEPA) filter placed after the vacuum cleaner bag and the motor within a sealed exhaust system. This vacuum cleaner removed the KCl particles that escaped the vacuum cleaner bag and the particles emitted by the motor. Results obtained for the KCl

  15. ALADINA - an unmanned research aircraft for observing vertical and horizontal distributions of ultrafine particles within the atmospheric boundary layer

    NASA Astrophysics Data System (ADS)

    Altstädter, B.; Platis, A.; Wehner, B.; Scholtz, A.; Wildmann, N.; Hermann, M.; Käthner, R.; Baars, H.; Bange, J.; Lampert, A.

    2015-04-01

    This paper presents the unmanned research aircraft Carolo P360 "ALADINA" (Application of Light-weight Aircraft for Detecting IN situ Aerosol) for investigating the horizontal and vertical distribution of ultrafine particles in the atmospheric boundary layer (ABL). It has a wingspan of 3.6 m, a maximum take-off weight of 25 kg and is equipped with aerosol instrumentation and meteorological sensors. A first application of the system, together with the unmanned research aircraft MASC (Multi-Purpose Airborne Carrier) of the Eberhard Karls University of Tübingen (EKUT), is described. As small payload for ALADINA, two condensation particle counters (CPC) and one optical particle counter (OPC) were miniaturised by re-arranging the vital parts and composing them in a space-saving way in the front compartment of the airframe. The CPCs are improved concerning the lower detection threshold and the response time to less than 1.3 s. Each system was characterised in the laboratory and calibrated with test aerosols. The CPCs are operated in this study with two different lower detection threshold diameters of 11 and 18 nm. The amount of ultrafine particles, which is an indicator for new particle formation, is derived from the difference in number concentrations of the two CPCs (ΔN). Turbulence and thermodynamic structure of the boundary layer are described by measurements of fast meteorological sensors that are mounted at the aircraft nose. A first demonstration of ALADINA and a feasibility study were conducted in Melpitz near Leipzig, Germany, at the Global Atmosphere Watch (GAW) station of the Leibniz Institute for Tropospheric Research (TROPOS) on 2 days in October 2013. There, various ground-based instruments are installed for long-term atmospheric monitoring. The ground-based infrastructure provides valuable additional background information to embed the flights in the continuous atmospheric context and is used for validation of the airborne results. The development of the

  16. Aircraft de-icer: Recycling can cut carbon emissions in half

    SciTech Connect

    Johnson, Eric P.

    2012-01-15

    Flight-safety regulations in most countries require aircraft to be ice-free upon takeoff. In icy weather, this means that the aircraft usually must be de-iced (existing ice is removed) and sometimes anti-iced (to protect against ice-reformation). For both processes, aircraft typically are sprayed with an 'antifreeze' solution, consisting mainly of glycol diluted with water. This de/anti-icing creates an impact on the environment, of which environmental regulators have grown increasingly conscious. The US Environmental Protection Agency (EPA), for example, recently introduced stricter rules that require airports above minimum size to collect de-icing effluents and send them to wastewater treatment. De-icer collection and treatment is already done at most major airports, but a few have gone one step further: rather than putting the effluent to wastewater, they recycle it. This study examines the carbon savings that can be achieved by recycling de-icer. There are two key findings. One, recycling, as opposed to not recycling, cuts the footprint of aircraft de-icing by 40-50% - and even more, in regions where electricity-generation is cleaner. Two, recycling petrochemical-based de-icer generates a 15-30% lower footprint than using 'bio' de-icer without recycling. - Highlights: Black-Right-Pointing-Pointer Carbon footprint of aircraft de-icing can be measured. Black-Right-Pointing-Pointer Recycling aircraft de-icer cuts the footprint of aircraft de-icing by 40-50%. Black-Right-Pointing-Pointer Recycling 'fossil' de-icer is lower carbon than not recycling 'bio' de-icer.

  17. Effects of engine emissions from high-speed civil transport aircraft: A two-dimensional modeling study, part 2

    NASA Technical Reports Server (NTRS)

    Ko, Malcolm K. W.; Weisenstein, Debra K.; Sze, Nein Dak; Shia, Run-Lie; Rodriguez, Jose M.; Heisey, Curtis

    1991-01-01

    The AER two-dimensional chemistry-transport model is used to study the effect of supersonic and subsonic aircraft operation in the 2010 atmosphere on stratospheric ozone (O3). The results show that: (1) the calculated O3 response is smaller in the 2010 atmosphere compared to previous calculations performed in the 1980 atmosphere; (2) with the emissions provided, the calculated decrease in O3 column is less than 1 percent; and (3) the effect of model grid resolution on O3 response is small provided that the physics is not modified.

  18. [Research on NEDC ultrafine particle emission characters of a port fuel injection gasoline car].

    PubMed

    Hu, Zhi-Yuan; Li, Jin; Tan, Pi-Qiang; Lou, Di-Ming

    2012-12-01

    A Santana gasoline car with multi-port fuel injection (PFI) system was used as the research prototype and an engine exhaust particle sizer (EEPS) was employed to investigate the exhaust ultrafine particle number and size distribution characters of the tested vehicle in new European driving cycle (NEDC). The tested results showed that the vehicle's nuclear particle number, accumulation particle number, as well as the total particle number emission increased when the car drove in accelerated passage, and the vehicle's particle number emission was high during the first 40 seconds after test started and when the speed was over 90 km x h(-1) in extra urban driving cycle (EUDC) in NEDC. The ultrafine particle distribution of the whole NEDC showed a single peak logarithmic distribution, with diameters of the peak particle number emission ranging from 10 nm to 30 nm, and the geometric mean diameter was 24 nm. The ultrafine particle distribution of the urban driving cycle named by the economic commission for Europe (ECE) e. g. ECE I, ECE II - IV, the extra urban driving cycle e. g. EUDC, and the idling, constant speed, acceleration, deceleration operation conditions of NEDC all showed a single peak logarithmic distribution, also with particle diameters of the peak particle number emission ranging from 10 nm to 30 nm, and the geometric mean diameters of different driving cycle and different driving mode were from 14 nm to 42 nm. Therefore, the ultrafine particle emissions of the tested PFI gasoline car were mainly consisted of nuclear mode particles with a diameter of less than 50 nm.

  19. ALADINA - an unmanned research aircraft for observing vertical and horizontal distributions of ultrafine particles within the atmospheric boundary layer

    NASA Astrophysics Data System (ADS)

    Altstädter, B.; Platis, A.; Wehner, B.; Scholtz, A.; Lampert, A.; Wildmann, N.; Hermann, M.; Käthner, R.; Bange, J.; Baars, H.

    2014-12-01

    This paper presents the unmanned research aircraft Carolo P360 "ALADINA" (Application of Light-weight Aircraft for Detecting IN-situ Aerosol) for investigating the horizontal and vertical distribution of ultrafine particles in the atmospheric boundary layer (ABL). It has a wingspan of 3.6 m, a maximum take-off weight of 25 kg and is equipped with aerosol instrumentation and meteorological sensors. A first application of the system, together with the unmanned research aircraft MASC (Multi-Purpose Airborne Carrier) of the Eberhard-Karls University of Tübingen (EKUT), is described. As small payload for ALADINA, two condensation particle counters (CPC) and one optical particle counter (OPC) were miniaturized by re-arranging the vital parts and composing them in a space saving way in the front compartment of the airframe. The CPCs are improved concerning the lower detection threshold and the response time. Each system was characterized in the laboratory and calibrated with test aerosols. The CPCs are operated with two different lower detection threshold diameters of 6 and 18 nm. The amount of ultrafine particles, which is an indicator for new particle formation, is derived from the difference in number concentrations of the two CPCs. Turbulence and thermodynamic structure of the boundary layer are described by measurements of fast meteorological sensors that are mounted at the aircraft nose. A first demonstration of ALADINA and a feasibility study were conducted in Melpitz near Leipzig, Germany, at the Global Atmosphere Watch (GAW) station of the Leibniz Institute for Tropospheric Research (TROPOS) on two days in October 2013. There, various ground-based instruments are installed for long-term atmospheric monitoring. The ground-based infrastructure provides valuable additional background information to embed the flights in the continuous atmospheric context and is used for validation of the airborne results. The development of the boundary layer, derived from

  20. Aircraft observations of ultrafine particles and CCN from the boundary layer to the free troposphere in the Arctic summertime

    NASA Astrophysics Data System (ADS)

    Burkart, Julia; Willis, Megan; Bozem, Heiko; Hoor, Peter; Köllner, Franziska; Schneider, Johannes; Brauner, Ralf; Konrad, Christian; Herber, Andreas; Leaitch, Richard; Abbatt, Jon

    2016-04-01

    The Arctic is one of the regions most sensitive to climate change. The shrinking extent of sea ice during the Arctic summertime increases the area covered by open ocean, which likely impacts Arctic aerosol, cloud properties, and thus climate. In this context extensive aerosol measurements (aerosol composition, particle number and size, cloud condensation nuclei, and trace gases) have been made during the NETCARE 2014 summer campaign from the Polar 6 aircraft. The Polar 6 is an adopted DC-3 aircraft owned by the Alfred Wegener Institute in Bremerhaven, Germany. In July 2014 eleven flights were conducted out of Resolute Bay. Flights included vertical profiles from as low as 60 m up to 3 km, as well as several low-level flights covering diverse terrains such as open ocean, fast ice, melt ponds, and polynyas. Here we discuss the vertical distribution of ultrafine particles (UFP, dp: 5 - 20 nm), size distributions of larger particles (dp: 20 nm to 1 μm), and cloud condensation nuclei (CCN) in relation to different meteorological conditions and terrains. UFPs have been observed predominantly within the boundary layer, where concentrations reached several hundreds and occasionally even a few thousand particles per cubic centimeter. Highest concentrations were observed above open ocean and at the top of low-level clouds. During such events, the dominant mode of the size distribution was below 20 nm. However, in a few cases this ultrafine mode extended to sizes larger than 40 nm, suggesting that these UFP can grow into the CCN size range and thereby impact cloud properties and become climatically relevant.

  1. Fine Particle Emissions from Residual Fuel Oil Combustion: Characterization and Mechanisms of Formation

    DTIC Science & Technology

    2000-08-04

    NC, 1999. 3 . Bachmann, J. D ., Damberg, R. J., Caldwell, J. C., Ed- wards, C., and Koman, P. D ., Review of the National Ambient Air Quality Standards...residual fuel oil combustion to be suspect, as far as emission of toxic fine particles is concerned. Build- ing upon previous work examining the...control number. 1. REPORT DATE 04 AUG 2000 2. REPORT TYPE N/A 3 . DATES COVERED - 4. TITLE AND SUBTITLE Fine Particle Emissions from Residual

  2. Emissions of CH4 from natural gas production in the United States using aircraft-based observations

    NASA Astrophysics Data System (ADS)

    Sweeney, Colm; Karion, Anna; Petron, Gabrielle; Ryerson, Thomas; Peischl, Jeff; Trainer, Michael; Rella, Chris; Hardesty, Michael; Crosson, Eric; Montzka, Stephen; Tans, Pieter; Shepson, Paul; Kort, Eric

    2014-05-01

    New extraction technologies are making natural gas from shale and tight sand gas reservoirs in the United States (US) more accessible. As a result, the US has become the largest producer of natural gas in the world. This growth in natural gas production may result in increased leakage of methane, a potent greenhouse gas, offsetting the climate benefits of natural gas relative to other fossil fuels. Methane emissions from natural gas production are not well quantified because of the large variety of potential sources, the variability in production and operating practices, the uneven distribution of emitters, and a lack of verification of emission inventories with direct atmospheric measurements. Researchers at the NOAA Earth System Research Laboratory (ESRL) have used simple mass balance approaches in combination with isotopes and light alkanes to estimate emissions of CH4 from several natural gas and oil plays across the US. We will summarize the results of the available aircraft and ground-based atmospheric emissions estimates to better understand the spatial and temporal distribution of these emissions in the US.

  3. Emission of charged particles from excited compound nucleus

    SciTech Connect

    Kalandarov, Sh. A.; Adamian, G. G.; Antonenko, N. V.

    2010-11-24

    The formation and decay of excited compound nucleus are studied within the dinuclear system model[1]. The cross sections of complex fragment emission are calculated and compared with experimental data for the reactions {sup 3}He+{sup 108}Ag, {sup 78,82}Kr+{sup 12}C. Angular momentum dependence of cluster emission in {sup 78}Kr+{sup 12}C and {sup 40}Ca+{sup 78}Kr reactions is demonstrated.

  4. Ultrafine particle emission of waste incinerators and comparison to the exposure of urban citizens.

    PubMed

    Buonanno, Giorgio; Morawska, Lidia

    2015-03-01

    On the basis of the growing interest on the impact of airborne particles on human exposure as well as the strong debate in Western countries on the emissions of waste incinerators, this work reviewed existing literature to: (i) show the emission factors of ultrafine particles (particles with a diameter less than 100 nm) of waste incinerators; and (ii) assess the contribution of waste incinerators in terms of ultrafine particles to exposure and dose of people living in the surrounding areas of the plants in order to estimate eventual risks. The review identified only a limited number of studies measuring ultrafine particle emissions, and in general they report low particle number concentrations at the stack (the median value was equal to 5.5×10(3) part cm(-3)), in most cases higher than the outdoor background value. The lowest emissions were achieved by utilization of the bag-house filter which has an overall number-based filtration efficiency higher than 99%. Referring to reference case, the corresponding emission factor is equal to 9.1×10(12) part min(-1), that is lower than one single high-duty vehicle. Since the higher particle number concentrations found in the most contributing microenvironments to the exposure (indoor home, transportation, urban outdoor), the contribution of the waste incinerators to the daily dose can be considered as negligible.

  5. Particle and gas emissions from a simulated coal-burning household fire pit

    SciTech Connect

    Linwei Tian; Donald Lucas; Susan L. Fischer; S. C. Lee; S. Katharine Hammond; Catherine P. Koshland

    2008-04-01

    An open fire was assembled with firebricks to simulate the household fire pit used in rural China, and 15 different coals from this area were burned to measure the gaseous and particulate emissions. Particle size distribution was studied with a microorifice uniform-deposit impactor (MOUDI). Over 90% of the particulate mass was attributed to sub-micrometer particles. The carbon balance method was used to calculate the emission factors. Emission factors for four pollutants (particulate matter, CO{sub 2}, total hydrocarbons, and NOx) were 2-4 times higher for bituminous coals than for anthracites. In past inventories of carbonaceous emissions used for climate modeling, these two types of coal were not treated separately. The dramatic emission factor difference between the two types of coal warrants attention in the future development of emission inventories. 25 refs., 8 figs., 1 tab.

  6. Time-dependent effects in the radially streaming particle model. [quasars and Seyfert galaxy emission

    NASA Technical Reports Server (NTRS)

    Hubbard, R.

    1975-01-01

    The radially streaming particle model for broad quasar and Seyfert galaxy emission features is modified to include sources of time dependence. The results seem to correlate with reported observations of multiple components, variability, and transient features in the wings of Seyfert and quasi-stellar emission lines.

  7. Characterization of Gas and Particle Emissions from Laboratory Burns of Peat

    EPA Science Inventory

    Peat cores collected from two locations in eastern North Carolina (NC, USA) were burned in a laboratory facility to characterize emissions during simulated field combustion. Particle and gas samples were analyzed to quantify emission factors for particulate matter (PM2.5), organi...

  8. WOOD STOVE EMISSIONS: PARTICLE SIZE AND CHEMICAL COMPOSITION

    EPA Science Inventory

    The report summarizes wood stove particle size and chemical composition data gathered to date. [NOTE: In 1995, EPA estimated that residential wood combustion (RWC), including fireplaces, accounted for a significant fraction of national particulate matter with aerodynamic diameter...

  9. Procedure for generating global atmospheric engine emissions data from future supersonic transport aircraft. The 1990 high speed civil transport studies

    NASA Technical Reports Server (NTRS)

    Sohn, R. A.; Stroup, J. W.

    1990-01-01

    The input for global atmospheric chemistry models was generated for baseline High Speed Civil Transport (HSCT) configurations at Mach 1.6, 2.2, and 3.2. The input is supplied in the form of number of molecules of specific exhaust constituents injected into the atmosphere per year by latitude and by altitude (for 2-D codes). Seven exhaust constituents are currently supplied: NO, NO2, CO, CO2, H2O, SO2, and THC (Trace Hydrocarbons). An eighth input is also supplied, NO(x), the sum of NO and NO2. The number of molecules of a given constituent emitted per year is a function of the total fuel burned by a supersonic fleet and the emission index (EI) of the aircraft engine for the constituent in question. The EIs for an engine are supplied directly by the engine manufacturers. The annual fuel burn of a supersonic fleet is calculated from aircraft performance and economic criteria, both of which are strongly dependent on basic design parameters such as speed and range. The altitude and latitude distribution of the emission is determined based on 10 Intern. Air Transport Assoc. (IATA) regions chosen to define the worldwide route structure for future HSCT operations and the mission flight profiles.

  10. Detection of Bioaerosols using Single Particle Thermal Emission Spectroscopy

    DTIC Science & Technology

    2013-03-01

    the optical void(s) created by the aberration. Particle materials successfully trapped include carbon, silica, ragweed pollen , albumin, and...of-concept study will yield similar results when applied to a larger set of biologically derived materials, e.g., pollen , amino acids, proteins...Chang, R. Dual-excitation- wavelength Fluorescence and Elastic Scattering for Differentiation of Single Airborne Pollen and Fungal Particles

  11. SPECIATION OF GAS-PHASE AND FINE PARTICLE EMISSIONS FROM BURNING OF FOLIAR FUELS

    EPA Science Inventory

    Particle size distributions (10-1000 nm aerodynamic diameter), physical and chemical properties of fine particle matter (PM2.5) with aerodynamic diameter <2.5 micrometers, and gas-phase emissions from controlled open burning of assorted taxa were measured. Chemical speciation of ...

  12. Emission of ultrafine particles from the incineration of municipal solid waste: A review

    NASA Astrophysics Data System (ADS)

    Jones, Alan M.; Harrison, Roy M.

    2016-09-01

    Ultrafine particles (diameter <100 nm) are of great topical interest because of concerns over possible enhanced toxicity relative to larger particles of the same composition. While combustion processes, and especially road traffic exhaust are a known major source of ultrafine particle emissions, relatively little is known of the magnitude of emissions from non-traffic sources. One such source is the incineration of municipal waste, and this article reviews studies carried out on the emissions from modern municipal waste incinerators. The effects of engineering controls upon particle emissions are considered, as well as the very limited information on the effects of changing waste composition. The results of measurements of incinerator flue gas, and of atmospheric sampling at ground level in the vicinity of incinerators, show that typical ultrafine particle concentrations in flue gas are broadly similar to those in urban air and that consequently, after the dispersion process dilutes incinerator exhaust with ambient air, ultrafine particle concentrations are typically indistinguishable from those that would occur in the absence of the incinerator. In some cases the ultrafine particle concentration in the flue gas may be below that in the local ambient air. This appears to be a consequence of the removal of semi-volatile vapours in the secondary combustion zone and abatement plant, and the high efficiency of fabric filters for ultrafine particle collection.

  13. Emission, absorption and polarization of gyrosynchrotron radiation of mildly relativistic particles

    NASA Technical Reports Server (NTRS)

    Petrosian, V.; Mctiernan, J. M.

    1983-01-01

    Approximate analytic expressions are presented for the emissivity and absorption coefficient of synchrotron radiation of mildly relativistic particles with an arbitrary energy spectrum and pitch angle distribution. From these, an expression for the degree of polarization is derived. The analytic results are compared with numerical results for both thermal and non-thermal (power law) distributions of particles.

  14. Method and apparatus for calibrating a particle emissions monitor

    DOEpatents

    Flower, William L.; Renzi, Ronald F.

    1998-07-07

    The instant invention discloses method and apparatus for calibrating particulate emissions monitors, in particular, and sampling probes, in general, without removing the instrument from the system being monitored. A source of one or more specific metals in aerosol (either solid or liquid) or vapor form is housed in the instrument. The calibration operation is initiated by moving a focusing lens, used to focus a light beam onto an analysis location and collect the output light response, from an operating position to a calibration position such that the focal point of the focusing lens is now within a calibration stream issuing from a calibration source. The output light response from the calibration stream can be compared to that derived from an analysis location in the operating position to more accurately monitor emissions within the emissions flow stream.

  15. Method and apparatus for calibrating a particle emissions monitor

    DOEpatents

    Flower, W.L.; Renzi, R.F.

    1998-07-07

    The invention discloses a method and apparatus for calibrating particulate emissions monitors, in particular, sampling probes, and in general, without removing the instrument from the system being monitored. A source of one or more specific metals in aerosol (either solid or liquid) or vapor form is housed in the instrument. The calibration operation is initiated by moving a focusing lens, used to focus a light beam onto an analysis location and collect the output light response, from an operating position to a calibration position such that the focal point of the focusing lens is now within a calibration stream issuing from a calibration source. The output light response from the calibration stream can be compared to that derived from an analysis location in the operating position to more accurately monitor emissions within the emissions flow stream. 6 figs.

  16. Emission of charged particles from excited compound nuclei

    SciTech Connect

    Kalandarov, Sh. A.; Adamian, G. G.; Antonenko, N. V.; Scheid, W.

    2010-10-15

    The process of complex fragment emission is studied within the dinuclear system model. Cross sections of complex fragment emission are calculated and compared with experimental data for the reactions {sup 3}He+{sup nat}Ag, {sup 78,86}Kr+{sup 12}C, and {sup 63}Cu+{sup 12}C. The mass distributions of the products of these reactions, isotopic distributions for the {sup 3}He+{sup nat}Ag and {sup 78}Kr+{sup 12}C reactions, and average total kinetic energies of the products of the {sup 78}Kr+{sup 12}C reaction are predicted.

  17. Numerical simulations of the charged-particle flow dynamics for sources with a curved emission surface

    NASA Astrophysics Data System (ADS)

    Altsybeyev, V. V.

    2016-12-01

    The implementation of numerical methods for studying the dynamics of particle flows produced by pulsed sources is discussed. A particle tracking method with so-called gun iteration for simulations of beam dynamics is used. For the space charge limited emission problem, we suggest a Gauss law emission model for precise current-density calculation in the case of a curvilinear emitter. The results of numerical simulations of particle-flow formation for cylindrical bipolar diode and for diode with elliptical emitter are presented.

  18. Massive-scale aircraft observations of giant sea-salt aerosol particle size distributions in atmospheric marine boundary layers

    NASA Astrophysics Data System (ADS)

    Jensen, J. B.

    2015-12-01

    iant sea-salt aerosol particles (dry radius, rd > 0.5 μm) occur nearly everywhere in the marine boundary layer and frequently above. This study presents observations of atmospheric sea-salt size distributions in the range 0.7 < rd < 14 μm based on external impaction of sea-spray aerosol particles onto microscope polycarbonate microscope slides. The slides have very large sample volumes, typically about 250 L over a 10-second sampling period. This provides unprecedented sampling of giant sea-salt particles for flights in marine boundary layer air. The slides were subsequently analyzed in a humidified chamber using dual optical digital microscopy. At a relative humidity of 90% the sea-salt aerosol particles form spherical cap drops. Based on measurement the volume of the spherical cap drop and assuming NaCl composition, the Kohler equation is used to derive the dry salt mass of tens of thousands of individual aerosol particles on each slide. Size distributions are given with a 0.2 μm resolution. The slides were exposed from the NSF/NCAR C-130 research aircraft during the 2008 VOCALS project off the coast of northern Chile and the 2011 ICE-T in the Caribbean. In each deployment, size distributions using hundreds of slides are used to relate fitted log-normal size distributions parameters to wind speed, altitude and other atmospheric conditions. The size distributions provide a unique observational set for initializing cloud models with coarse-mode aerosol particle observations for marine atmospheres.

  19. SLAC T-510: Radio emission from particle cascades in the presence of a magnetic field

    NASA Astrophysics Data System (ADS)

    Mulrey, Katharine

    2017-03-01

    Cosmic ray induced particle cascades radiate in radio frequencies in the Earth's atmosphere. Geomagnetic and Askaryan emission provide an effective way to detect ultra-high energy cosmic rays. The SLAC T-510 experiment was the first to measure magnetically induced radiation from particle cascades in a controlled laboratory setting. An electron beam incident upon a dense dielectric target produced a particle cascade in the presence of a variable magnetic field. Antennas covering a band of 30-3000 MHz sampled RF emission in vertical and horizontal polarizations. Results from T-510 are compared to particle-level RF-emission simulations which are critical for reconstructing the energy and composition of detected ultra-high energy cosmic ray air showers. We discuss the experimental set up, the data processing, the systematic errors and the main results of the experiment, which we found in a good agreement with the simulations.

  20. Assessment of Small-Particle Emissions (Less Than 2 Micron).

    ERIC Educational Resources Information Center

    Shannon, Larry J.; And Others

    This paper is based on a particulate pollutant system study to delineate the deficiencies in knowledge regarding the nature and magnitude of particulate pollutant emissions from stationary sources. Presented at the 12th Conference on Methods in Air Pollution and Industrial Hygiene Studies, University of Southern California, April, 1971, it focuses…

  1. Particle emissions from microalgae biodiesel combustion and their relative oxidative potential.

    PubMed

    Rahman, M M; Stevanovic, S; Islam, M A; Heimann, K; Nabi, M N; Thomas, G; Feng, B; Brown, R J; Ristovski, Z D

    2015-09-01

    Microalgae are considered to be one of the most viable biodiesel feedstocks for the future due to their potential for providing economical, sustainable and cleaner alternatives to petroleum diesel. This study investigated the particle emissions from a commercially cultured microalgae and higher plant biodiesels at different blending ratios. With a high amount of long carbon chain lengths fatty acid methyl esters (C20 to C22), the microalgal biodiesel used had a vastly different average carbon chain length and level of unsaturation to conventional biodiesel, which significantly influenced particle emissions. Smaller blend percentages showed a larger reduction in particle emission than blend percentages of over 20%. This was due to the formation of a significant nucleation mode for the higher blends. In addition measurements of reactive oxygen species (ROS), showed that the oxidative potential of particles emitted from the microalgal biodiesel combustion were lower than that of regular diesel. Biodiesel oxygen content was less effective in suppressing particle emissions for biodiesels containing a high amount of polyunsaturated C20-C22 fatty acid methyl esters and generated significantly increased nucleation mode particle emissions. The observed increase in nucleation mode particle emission is postulated to be caused by very low volatility, high boiling point and high density, viscosity and surface tension of the microalgal biodiesel tested here. Therefore, in order to achieve similar PM (particulate matter) emission benefits for microalgal biodiesel likewise to conventional biodiesel, fatty acid methyl esters (FAMEs) with high amounts of polyunsaturated long-chain fatty acids (≥C20) may not be desirable in microalgal biodiesel composition.

  2. [Experimental study on the size spectra and emission factor of ultrafine particle from coal combustion].

    PubMed

    Sun, Zai; Yang, Wen-jun; Xie, Xiao-fang; Chen, Qiu-fang; Cai, Zhi-liang

    2014-12-01

    The emission characteristics of ultrafine particles released from pulverized coal combustion were studied, the size spectra of ultrafine particles (5.6-560 nm) were measured with FMPS (fast mobility particle sizer) on a self-built aerosol experiment platform. Meanwhile, a particle dynamic evolution model was established to obtain the particle deposition rate and the emission rate through the optimized algorithm. Finally, the emission factor was calculated. The results showed that at the beginning of particle generation, the size spectra were polydisperse and complex, the initial size spectra was mainly composed of three modes including 10 nm, 30-40 nm and 100-200 nm. Among them, the number concentration of mode around 10 nm was higher than those of other modes, the size spectrum of around 100-200 nm was lognormal distributed, with a CMD (count median diameter) of around 16 nm. Then, as time went on, the total number concentration was decayed by exponential law, the CMD first increased and then tended to be stable gradually. The calculation results showed that the emission factor of particles from coal combustion under laboratory condition was (5.54 x 10(12) ± 2.18 x 10(12)) unit x g(-1).

  3. Additive impacts on particle emissions from heating low emitting cooking oils

    NASA Astrophysics Data System (ADS)

    Amouei Torkmahalleh, M.; Zhao, Y.; Hopke, P. K.; Rossner, A.; Ferro, A. R.

    2013-08-01

    The effect of five additives, including table salt, sea salt, black pepper, garlic powder, and turmeric, on the emission of PM2.5 and ultrafine particles (UFP) from heated cooking oil (200 °C) were studied. One hundred milligrams of the additives were added individually to either canola or soybean oil without stirring. Black pepper, table salt, and sea salt reduced the PM2.5 emission of canola oil by 86% (p < 0.001), 88% (p < 0.001), and 91% (p < 0.001), respectively. Black pepper, table salt, and sea salt also decreased the total particle number emissions of canola oil by 45% (p = 0.003), 52% (p = 0.001), and 53% (p < 0.001), respectively. Turmeric and garlic powder showed no changes in the PM2.5 and total number emissions of canola oil. Table salt and sea salt, decreased the level of PM2.5 emissions from soybean oil by 47% (p < 0.001) and 77% (p < 0.001), respectively. No differences in the PM2.5 emissions were observed when other additives were added to soybean oil. Black pepper, sea salt, and table salt reduced the total particle number emissions from the soybean oil by 51%, 61% and 68% (p < 0.001), respectively. Turmeric and garlic powder had no effect on soybean oil with respect to total particle number emissions. Our results indicate that table salt, sea salt, and black pepper can be used to reduce the particle total number and PM2.5 emissions when cooking with oil.

  4. Particle Acceleration, Magnetic Field Generation, and Emission in Relativistic Shocks

    NASA Technical Reports Server (NTRS)

    Nishikawa, Ken-IchiI.; Hededal, C.; Hardee, P.; Richardson, G.; Preece, R.; Sol, H.; Fishman, G.

    2004-01-01

    Shock acceleration is an ubiquitous phenomenon in astrophysical plasmas. Plasma waves and their associated instabilities (e.g., the Buneman instability, two-streaming instability, and the Weibel instability) created in the shocks are responsible for particle (electron, positron, and ion) acceleration. Using a 3-D relativistic electromagnetic particle (m) code, we have investigated particle acceleration associated with a relativistic jet front propagating through an ambient plasma with and without initial magnetic fields. We find only small differences in the results between no ambient and weak ambient parallel magnetic fields. Simulations show that the Weibel instability created in the collisionless shock front accelerates particles perpendicular and parallel to the jet propagation direction. New simulations with an ambient perpendicular magnetic field show the strong interaction between the relativistic jet and the magnetic fields. The magnetic fields are piled up by the jet and the jet electrons are bent, which creates currents and displacement currents. At the nonlinear stage, the magnetic fields are reversed by the current and the reconnection may take place. Due to these dynamics the jet and ambient electron are strongly accelerated in both parallel and perpendicular directions.

  5. Determination of the emissions from an aircraft auxiliary power unit (APU) during the Alternative Aviation Fuel Experiment (AAFEX).

    PubMed

    Kinsey, John S; Timko, Michael T; Herndon, Scott C; Wood, Ezra C; Yu, Zhenhong; Miake-Lye, Richard C; Lobo, Prem; Whitefield, Philip; Hagen, Donald; Wey, Changlie; Anderson, Bruce E; Beyersdorf, Andreas J; Hudgins, Charles H; Thornhill, K Lee; Winstead, Edward; Howard, Robert; Bulzan, Dan I; Tacina, Kathleen B; Knighton, W Berk

    2012-04-01

    The emissions from a Garrett-AiResearch (now Honeywell) Model GTCP85-98CK auxiliary power unit (APU) were determined as part of the National Aeronautics and Space Administration's (NASA's) Alternative Aviation Fuel Experiment (AAFEX) using both JP-8 and a coal-derived Fischer Tropsch fuel (FT-2). Measurements were conducted by multiple research organizations for sulfur dioxide (SO2, total hydrocarbons (THC), carbon monoxide (CO), carbon dioxide (CO2), nitrogen oxides (NOx), speciated gas-phase emissions, particulate matter (PM) mass and number, black carbon, and speciated PM. In addition, particle size distribution (PSD), number-based geometric mean particle diameter (GMD), and smoke number were also determined from the data collected. The results of the research showed PM mass emission indices (EIs) in the range of 20 to 700 mg/kg fuel and PM number EIs ranging from 0.5 x 10(15) to 5 x 10(15) particles/kg fuel depending on engine load and fuel type. In addition, significant reductions in both the SO2 and PM EIs were observed for the use of the FT fuel. These reductions were on the order of approximately 90% for SO2 and particle mass EIs and approximately 60% for the particle number EI, with similar decreases observed for black carbon. Also, the size of the particles generated by JP-8 combustion are noticeably larger than those emitted by the APU burning the FT fuel with the geometric mean diameters ranging from 20 to 50 nm depending on engine load and fuel type. Finally, both particle-bound sulfate and organics were reduced during FT-2 combustion. The PM sulfate was reduced by nearly 100% due to lack of sulfur in the fuel, with the PM organics reduced by a factor of approximately 5 as compared with JP-8.

  6. Particle Emission and Charging Effects Induced by Fracture

    DTIC Science & Technology

    1989-06-15

    recombination with mobile charge carriers). These processes are initiated by bond breaking resulting in the creation of localized departures from...subsequendy decay to yield after-emission. Thermally stimulated relaxation involving mobile charge carriers releasing energy at appropriate recombination...region of contact. This flow of charge is slow because of the poor charge mobility in the rubber. In addition, any oxide layer on the metal also

  7. Heterogeneous Chemistry Related to Stratospheric Aircraft

    NASA Technical Reports Server (NTRS)

    Tolbert, Margaret A.

    1995-01-01

    Emissions from stratospheric aircraft that may directly or indirectly affect ozone include NO(y), H2O, soot and sulfuric acid. To fully assess the impact of such emissions, it is necessary to have a full understanding of both the homogeneous and heterogeneous transformations that may occur in the stratosphere. Heterogeneous reactions on stratospheric particles play a key role in partitioning ozone-destroying species between their active and reservoir forms. In particular, heterogeneous reactions tend to activate odd chlorine while deactivating odd nitrogen. Accurate modeling of the net atmospheric effects of stratospheric aircraft requires a thorough understanding of the competing effects of this activation/deactivation. In addition, a full understanding of the potential aircraft impacts requires that the abundance, composition and formation mechanisms of the particles themselves be established. Over the last three years with support from the High Speed Research Program, we have performed laboratory experiments to determine the chemical composition, formation mechanism, and reactivity of stratospheric aerosols.

  8. GASP cloud- and particle-encounter statistics and their application to LFC aircraft studies. Volume 2: Appendixes

    NASA Technical Reports Server (NTRS)

    Jasperson, W. H.; Nastron, G. D.; Davis, R. E.; Holdeman, J. D.

    1984-01-01

    Summary studies are presented for the entire cloud observation archive from the NASA Global Atmospheric Sampling Program (GASP). Studies are also presented for GASP particle-concentration data gathered concurrently with the cloud observations. Cloud encounters are shown on about 15 percent of the data samples overall, but the probability of cloud encounter is shown to vary significantly with altitude, latitude, and distance from the tropopause. Several meteorological circulation features are apparent in the latitudinal distribution of cloud cover, and the cloud-encounter statistics are shown to be consistent with the classical mid-latitude cyclone model. Observations of clouds spaced more closely than 90 minutes are shown to be statistically dependent. The statistics for cloud and particle encounter are utilized to estimate the frequency of cloud encounter on long-range airline routes, and to assess the probability and extent of laminaar flow loss due to cloud or particle encounter by aircraft utilizing laminar flow control (LFC). It is shown that the probability of extended cloud encounter is too low, of itself, to make LFC impractical. This report is presented in two volumes. Volume I contains the narrative, analysis, and conclusions. Volume II contains five supporting appendixes.

  9. GASP cloud- and particle-encounter statistics and their application to LPC aircraft studies. Volume 1: Analysis and conclusions

    NASA Technical Reports Server (NTRS)

    Jasperson, W. H.; Nastrom, G. D.; Davis, R. E.; Holdeman, J. D.

    1984-01-01

    Summary studies are presented for the entire cloud observation archieve from the NASA Global Atmospheric Sampling Program (GASP). Studies are also presented for GASP particle concentration data gathered concurrently with the cloud observations. Cloud encounters are shown on about 15 percent of the data samples overall, but the probability of cloud encounter is shown to vary significantly with altitude, latitude, and distance from the tropopause. Several meteorological circulation features are apparent in the latitudinal distribution of cloud cover, and the cloud encounter statistics are shown to be consistent with the classical mid-latitude cyclone model. Observations of clouds spaced more closely than 90 minutes are shown to be statistically dependent. The statistics for cloud and particle encounter are utilized to estimate the frequency of cloud encounter on long range airline routes, and to assess the probability and extent of laminar flow loss due to cloud or particle encounter by aircraft utilizing laminar flow control (LFC). It is shown that the probability of extended cloud encounter is too low, of itself, to make LFC impractical.

  10. Factors governing particle number emissions in a waste-to-energy plant.

    PubMed

    Ozgen, Senem; Cernuschi, Stefano; Giugliano, Michele

    2015-05-01

    Particle number concentration and size distribution measurements were performed on the stack gas of a waste-to-energy plant which co-incinerates municipal solid waste, sewage sludge and clinical waste in two lines. Average total number of particles was found to be 4.0·10(5)cm(-3) and 1.9·10(5)cm(-3) for the line equipped with a wet flue gas cleaning process and a dry cleaning system, respectively. Ultrafine particles (dp<100nm) accounted for about 97% of total number concentration for both lines, whereas the nanoparticle (dp<50nm) contribution differed slightly between the lines (87% and 84%). The experimental data is explored statistically through some multivariate pattern identifying methods such as factor analysis and cluster analysis to help the interpretation of the results regarding the origin of the particles in the flue gas with the objective of determining the factors governing the particle number emissions. The higher moisture of the flue gas in the wet cleaning process was found to increase the particle number emissions on average by a factor of about 2 due to increased secondary formation of nanoparticles through nucleation of gaseous precursors such as sulfuric acid, ammonia and water. The influence of flue gas dilution and cooling monitored through the variation of the sampling conditions also confirms the potential effect of the secondary new particle formation in increasing the particle number emissions. This finding shows the importance of reporting the experimental conditions in detail to enable the comparison and interpretation of particle number emissions. Regarding the fuel characteristics no difference was observed in terms of particle number concentration and size distributions between the clinical waste feed and the municipal solid waste co-incineration with sludge.

  11. Gas-particle partitioning of primary organic aerosol emissions: (1) Gasoline vehicle exhaust

    NASA Astrophysics Data System (ADS)

    May, Andrew A.; Presto, Albert A.; Hennigan, Christopher J.; Nguyen, Ngoc T.; Gordon, Timothy D.; Robinson, Allen L.

    2013-10-01

    The gas-particle partitioning of the primary organic aerosol (POA) emissions from fifty-one light-duty gasoline vehicles (model years 1987-2012) was investigated at the California Air Resources Board Haagen-Smit Laboratory. Each vehicle was operated over the cold-start unified cycle on a chassis dynamometer and its emissions were sampled using a constant volume sampler. Four independent yet complementary approaches were used to investigate POA gas-particle partitioning: sampling artifact correction of quartz filter data, dilution from the constant volume sampler into a portable environmental chamber, heating in a thermodenuder, and thermal desorption/gas chromatography/mass spectrometry analysis of quartz filter samples. This combination of techniques allowed gas-particle partitioning measurements to be made across a wide range of atmospherically relevant conditions - temperatures of 25-100 °C and organic aerosol concentrations of <1-600 μg m-3. The gas-particle partitioning of the POA emissions varied continuously over this entire range of conditions and essentially none of the POA should be considered non-volatile. Furthermore, for most vehicles, the low levels of dilution used in the constant volume sampler created particle mass concentrations that were greater than a factor of 10 or higher than typical ambient levels. This resulted in large and systematic partitioning biases in the POA emission factors compared to more dilute atmospheric conditions, as the POA emission rates may be over-estimated by nearly a factor of four due to gas-particle partitioning at higher particle mass concentrations. A volatility distribution was derived to quantitatively describe the measured gas-particle partitioning data using absorptive partitioning theory. Although the POA emission factors varied by more than two orders of magnitude across the test fleet, the vehicle-to-vehicle differences in gas-particle partitioning were modest. Therefore, a single volatility distribution

  12. An Atlas of extraterrestrial particles collected with NASA U-2 aircraft, 1974 - 1976

    NASA Technical Reports Server (NTRS)

    Brownlee, D. E.; Tomandl, D.; Blanchard, M. B.; Ferry, G. V.; Kyte, F.

    1976-01-01

    Extraterrestrial particles collected during U-2 flights in the stratosphere were divided into four groups: chondritic, iron-sulfur--nickel, mafic silicates, and others. The chondritic aggregates are typically composed of Fe, Mg, Si, C, S, Ca, and Ni. Detectable levels of He-4 implanted from the solar wind occur in some. Olivine, spinel, and possibly pyrrhotite and a hydrated layered-lattice silicate were identified. The chondritic ablation particles contain no sulfur and appear to have been melted. Magnetite, olivine, and pyroxene were identified. The iron-sulfur-nickel type particles resemble meteoritic iron sulfide with a small amount of nickel, and contain magnetite and troilite. The mafic silicate type particles are iron magnesium silicate grains with clumps of chondritic aggregate particles adhering to their surfaces. Olivine and possibly pyrrhotite and pyroxene were identified. Most of the iron-nickel type particles are spherules and include taenite and wustite. The other type particles include nickel-iron mounds on spheroidal glassy-like grains having chondritic-like elemental abundances.

  13. Particle and carbon dioxide emissions from passenger vehicles operating on unleaded petrol and LPG fuel.

    PubMed

    Ristovski, Z D; Jayaratne, E R; Morawska, L; Ayoko, G A; Lim, M

    2005-06-01

    A comprehensive study of the particle and carbon dioxide emissions from a fleet of six dedicated liquefied petroleum gas (LPG) powered and five unleaded petrol (ULP) powered new Ford Falcon Forte passenger vehicles was carried out on a chassis dynamometer at four different vehicle speeds--0 (idle), 40, 60, 80 and 100 km h(-1). Emission factors and their relative values between the two fuel types together with a statistical significance for any difference were estimated for each parameter. In general, LPG was found to be a 'cleaner' fuel, although in most cases, the differences were not statistically significant owing to the large variations between emissions from different vehicles. The particle number emission factors ranged from 10(11) to 10(13) km(-1) and was over 70% less with LPG compared to ULP. Corresponding differences in particle mass emission factor between the two fuels were small and ranged from the order of 10 microg km(-1) at 40 to about 1000 microg km(-1) at 100 km h(-1). The count median particle diameter (CMD) ranged from 20 to 35 nm and was larger with LPG than with ULP in all modes except the idle mode. Carbon dioxide emission factors ranged from about 300 to 400 g km(-1) at 40 km h(-1), falling with increasing speed to about 200 g km(-1) at 100 km h(-1). At all speeds, the values were 10% to 18% greater with ULP than with LPG.

  14. Non-invasive studies of multiphase flow in process equipment. Positron emission particle tracking technique

    NASA Astrophysics Data System (ADS)

    Balakin, B. V.; Adamsen, T. C. H.; Chang, Y.-F.; Kosinski, P.; Hoffmann, A. C.

    2017-01-01

    Positron emission particle tracking (PEPT) is a novel experimental technique for non-invasive inspection of industrial fluid/particle flows. The method is based on the dynamic positioning of a positron-emitting, flowing object (particle) performed through the sensing of annihilation events and subsequent numerical treatment to determine the particle position. The present paper shows an integrated overview of PEPT studies which were carried out using a new PET scanner in the Bergen University Hospital to study multiphase flows in different geometric configurations.

  15. A review of biomass burning emissions part II: intensive physical properties of biomass burning particles

    NASA Astrophysics Data System (ADS)

    Reid, J. S.; Koppmann, R.; Eck, T. F.; Eleuterio, D. P.

    2005-03-01

    The last decade has seen tremendous advances in atmospheric aerosol particle research that is often performed in the context of climate and global change science. Biomass burning, one of the largest sources of accumulation mode particles globally, has been closely studied for its radiative, geochemical, and dynamic impacts. These studies have taken many forms including laboratory burns, in situ experiments, remote sensing, and modeling. While the differing perspectives of these studies have ultimately improved our qualitative understanding of biomass-burning issues, the varied nature of the work make inter-comparisons and resolutions of some specific issues difficult. In short, the literature base has become a milieu of small pieces of the biomass-burning puzzle. This manuscript, the second part of four, examines the properties of biomass-burning particle emissions. Here we review and discuss the literature concerning the measurement of smoke particle size, chemistry, thermodynamic properties, and emission factors. Where appropriate, critiques of measurement techniques are presented. We show that very large differences in measured particle properties have appeared in the literature, in particular with regards to particle carbon budgets. We investigate emissions uncertainties using scale analyses, which shows that while emission factors for grass and brush are relatively well known, very large uncertainties still exist in emission factors of boreal, temperate and some tropical forests. Based on an uncertainty analysis of the community data set of biomass burning measurements, we present simplified models for particle size and emission factors. We close this review paper with a discussion of the community experimental data, point to lapses in the data set, and prioritize future research topics.

  16. A review of biomass burning emissions, part II: Intensive physical properties of biomass burning particles

    NASA Astrophysics Data System (ADS)

    Reid, J. S.; Koppmann, R.; Eck, T. F.; Eleuterio, D. P.

    2004-09-01

    The last decade has seen tremendous advances in atmospheric aerosol particle research that is often performed in the context of climate and global change science. Biomass burning, one of the largest sources of accumulation mode particles globally, has been closely studied for its radiative, geochemical, and dynamic impacts. These studies have taken many forms including laboratory burns, in situ experiments, remote sensing, and modeling. While the differing perspectives of these studies have ultimately improved our qualitative understanding of biomass burning issues, the varied nature of the work make inter-comparisons and resolutions of some specific issues difficult. In short, the literature base has become a milieu of small pieces of the biomass-burning puzzle. This manuscript, the second part of four, examines the properties of biomass-burning particle emissions. Here we review and discuss the literature concerning the measurement of smoke particle size, chemistry, thermodynamic properties, and emission factors. Where appropriate, critiques of measurement techniques are presented. We show that very large differences in measured particle properties have appeared in the literature, in particular with regards to particle carbon budgets. We investigate emissions uncertainties using scale analyses, which shows that while emission factors for grass and brush are relatively well known, very large uncertainties still exist in emission factors of boreal, temperate and some tropical forests. Based on an uncertainty analysis of the community data set of biomass burning measurements, we present simplified models for particle size and emission factors. We close this review paper with a discussion of the community experimental data, point to lapses in the data set, and prioritize future research topics.

  17. Real-World Emission of Particles from Vehicles: Volatility and the Effects of Ambient Temperature.

    PubMed

    Wang, Jonathan M; Jeong, Cheol-Heon; Zimmerman, Naomi; Healy, Robert M; Hilker, Nathan; Evans, Greg J

    2017-04-04

    A majority of the ultrafine particles observed in real-world conditions are systematically excluded from many measurements that help to guide regulation of vehicle emissions. To investigate the impact of this exclusion, coincident near-road particle number (PN) emission factors were quantified up- and downstream of a thermodenuder during two seasonal month-long campaigns with wide-ranging ambient temperatures (-19 to +30 °C) to determine the volatile fraction of particles. During colder temperatures (<0 °C), the volatile fraction of particles was 94%, but decreased to 85% during warmer periods (>20 °C). Additionally, mean PN emission factors were a factor of 3.8 higher during cold compared to warm periods. On the basis of 130 000 vehicle plumes including three additional campaigns, fleet mean emission factors were calculated for PN (8.5 × 10(14) kg-fuel(-1)), black carbon (37 mg kg-fuel(-1)), organic aerosol (51 mg kg-fuel(-1)), and particle-bound polycyclic aromatic hydrocarbons (0.7 mg kg-fuel(-1)). These findings demonstrate that significant differences exist between particles in thermally treated vehicle exhaust as compared to in real-world vehicle plumes to which populations in near-road environments are actually exposed. Furthermore, the magnitude of these differences are dependent upon season and may be more extreme in colder climates.

  18. Influence of Jet Fuel Composition on Aircraft Engine Emissions: A Synthesis of Aerosol Emissions Data from the NASA APEX, AAFEX, and ACCESS Missions

    NASA Astrophysics Data System (ADS)

    Moore, R.; Shook, M.; Beyersdorf, A. J.; Corr, C.; Herndon, S. C.; Knighton, W. B.; Miake-Lye, R. C.; Thornhill, K. L., II; Winstead, E.; Yu, Z.; Ziemba, L. D.; Anderson, B. E.

    2015-12-01

    We statistically analyze the impact of jet fuel properties on aerosols emitted by the NASA McDonnell Douglas DC-8 CFM56-2-C1 engines burning fifteen different aviation fuels. Data were collected for this single engine type during four different, comprehensive ground tests conducted over the past decade, which allow us to clearly link changes in aerosol emissions to fuel compositional changes. It is found that the volatile aerosol fraction dominates the number and volume emissions indices (EIs) over all engine powers, which are driven by changes in fuel aromatic and sulfur content. Meanwhile, the naphthalenic content of the fuel determines the magnitude of the non-volatile number and volume EI as well as the black carbon mass EI. Linear regression coefficients are reported for each aerosol EI in terms of these properties, engine fuel flow rate, and ambient temperature, and show that reducing both fuel sulfur content and napththalenes to near-zero levels would result in roughly a ten-fold decrease in aerosol number emitted per kg of fuel burn. This work informs future efforts to model aircraft emissions changes as the aviation fleet gradually begins to transition toward low-aromatic, low-sulfur alternative jet fuels from bio-based or Fischer-Tropsch production pathways.

  19. Evaluation of particle-induced X-ray emission and particle-induced γ-ray emission of quartz grains for forensic trace sediment analysis.

    PubMed

    Bailey, M J; Morgan, R M; Comini, P; Calusi, S; Bull, P A

    2012-03-06

    The independent verification in a forensics context of quartz grain morphological typing by scanning electron microscopy was demonstrated using particle-induced X-ray emission (PIXE) and particle-induced γ-ray emission (PIGE). Surface texture analysis by electron microscopy and high-sensitivity trace element mapping by PIXE and PIGE are independent analytical techniques for identifying the provenance of quartz in sediment samples in forensic investigations. Trace element profiling of the quartz grain matrix separately from the quartz grain inclusions served to differentiate grains of different provenance and indeed went some way toward discriminating between different quartz grain types identified in a single sample of one known forensic provenance. These results confirm the feasibility of independently verifying the provenance of critical samples from forensic cases.

  20. Particle emissions from a marine engine: chemical composition and aromatic emission profiles under various operating conditions.

    PubMed

    Sippula, O; Stengel, B; Sklorz, M; Streibel, T; Rabe, R; Orasche, J; Lintelmann, J; Michalke, B; Abbaszade, G; Radischat, C; Gröger, T; Schnelle-Kreis, J; Harndorf, H; Zimmermann, R

    2014-10-07

    The chemical composition of particulate matter (PM) emissions from a medium-speed four-stroke marine engine, operated on both heavy fuel oil (HFO) and distillate fuel (DF), was studied under various operating conditions. PM emission factors for organic matter, elemental carbon (soot), inorganic species and a variety of organic compounds were determined. In addition, the molecular composition of aromatic organic matter was analyzed using a novel coupling of a thermal-optical carbon analyzer with a resonance-enhanced multiphoton ionization (REMPI) mass spectrometer. The polycyclic aromatic hydrocarbons (PAHs) were predominantly present in an alkylated form, and the composition of the aromatic organic matter in emissions clearly resembled that of fuel. The emissions of species known to be hazardous to health (PAH, Oxy-PAH, N-PAH, transition metals) were significantly higher from HFO than from DF operation, at all engine loads. In contrast, DF usage generated higher elemental carbon emissions than HFO at typical load points (50% and 75%) for marine operation. Thus, according to this study, the sulfur emission regulations that force the usage of low-sulfur distillate fuels will also substantially decrease the emissions of currently unregulated hazardous species. However, the emissions of soot may even increase if the fuel injection system is optimized for HFO operation.

  1. [Emission characteristics of polycyclic aromatic hydrocarbons in exhaust particles from a diesel car].

    PubMed

    Tan, Pi-Qiang; Zhou, Zhou; Hu, Zhi-Yuan; Lou, Di-Ming

    2013-03-01

    The emission characteristics of polycyclic aromatic hydrocarbons (PAHs) in exhaust particles from a diesel car were studied. In the experiment, pure diesel fuel and B10 fuel with a biodiesel blend ratio of 10% were chosen. The gaseous emissions of HC, CO and NO(x) under New European Driving Cycle (NEDC) were measured, and exhaust particulate matter (PM) samples were analyzed by gas chromatography-mass spectrometry. The emission characteristics of PAHs in exhaust particles were highlighted. The results show that the emission concentrations of HC, CO, NO(x), and PM decreased when the diesel car used B10 fuel. Fluoranthene and pyrene were dominant in PAHs of PM emissions when the diesel car used pure diesel or B10 fuel. Compared to pure diesel, there was a slight increase in low-ring PAHs emissions when the diesel car used B10 fuel. On the contrary, PAHs emissions in middle and high-ring declined significantly. Besides, Benzo [ a] pyrene equivalent toxicity analysis results show that the BEQs of B10 fuel decreased by 21.6% compared to pure diesel. That means the toxicity of PAHs in exhaust particles declined when the diesel car used biodiesel fuel.

  2. Status of Technological Advancements for Reducing Aircraft Gas Turbine Engine Pollutant Emissions

    NASA Technical Reports Server (NTRS)

    Rudey, R. A.

    1975-01-01

    Combustor test rig results indicate that substantial reductions from current emission levels of carbon monoxide (CO), total unburned hydrocarbons (THC), oxides of nitrogen (NOx), and smoke are achievable by employing varying degrees of technological advancements in combustion systems. Minor to moderate modifications to existing conventional combustors produced significant reductions in CO and THC emissions at engine low power (idle/taxi) operating conditions but did not effectively reduce NOx at engine full power (takeoff) operating conditions. Staged combusiton techniques were needed to simultaneously reduce the levels of all the emissions over the entire engine operating range (from idle to takeoff). Emission levels that approached or were below the requirements of the 1979 EPA standards were achieved with the staged combustion systems and in some cases with the minor to moderate modifications to existing conventional combustion systems. Results from research programs indicate that an entire new generation of combustor technology with extremely low emission levels may be possible in the future.

  3. Effects of engine emissions from high-speed civil transport aircraft: A two-dimensional modeling study, part 1

    NASA Technical Reports Server (NTRS)

    Ko, Malcolm K. W.; Weisenstein, Debra K.; Sze, Nein Dak; Rodriguez, Jose M.; Heisey, Curtis

    1991-01-01

    The AER two-dimensional chemistry-transport model is used to study the effect on stratospheric ozone (O3) from operations of supersonic and subsonic aircraft. The study is based on six emission scenarios provided to AER. The study showed that: (1) the O3 response is dominated by the portion of the emitted nitrogen compounds that is entrained in the stratosphere; (2) the entrainment is a sensitive function of the altitude at which the material is injected; (3) the O3 removal efficiency of the emitted material depends on the concentrations of trace gases in the background atmosphere; and (4) evaluation of the impact of fleet operations in the future atmosphere must take into account the expected changes in trace gas concentrations from other activities. Areas for model improvements in future studies are also discussed.

  4. Cytotoxicity and inflammatory potential of soot particles of low-emission diesel engines.

    PubMed

    Su, Dang Sheng; Serafino, Annalucia; Müller, Jens-Oliver; Jentoft, Rolf E; Schlögl, Robert; Fiorito, Silvana

    2008-03-01

    We evaluated, in vitro, the inflammatory and cytotoxic potential of soot particles from current low-emission (Euro IV) diesel engines toward human peripheral blood monocyte-derived macrophage cells. The result is surprising. At the same mass concentration, soot particles produced under low-emission conditions exhibit a much highertoxic and inflammatory potential than particles from an old diesel engine operating under black smoke conditions. This effect is assigned to the defective surface structure of Euro IV diesel soot, rendering it highly active. Our findings indicate that the reduction of soot emission in terms of mass does not automatically lead to a reduction of the toxic effects toward humans when the structure and functionality of the soot is changed, and thereby the biological accessibility and inflammatory potential of soot is increased.

  5. Size-Resolved Source Emission Rates of Indoor Ultrafine Particles Considering Coagulation.

    PubMed

    Rim, Donghyun; Choi, Jung-Il; Wallace, Lance A

    2016-09-20

    Indoor ultrafine particles (UFP, <100 nm) released from combustion and consumer products lead to elevated human exposure to UFP. UFP emitted from the sources undergo aerosol transformation processes such as coagulation and deposition. The coagulation effect can be significant during the source emission due to high concentration and high mobility of nanosize particles. However, few studies have estimated size-resolved UFP source emission strengths while considering coagulation in their theoretical and experimental research work. The primary objective of this study is to characterize UFP source strength by considering coagulation in addition to other indoor processes (i.e., deposition and ventilation) in a realistic setting. A secondary objective is to test a hypothesis that size-resolved UFP source emission rates are unimodal and log-normally distributed for three common indoor UFP sources: an electric stove, a natural gas burner, and a paraffin wax candle. Experimental investigations were performed in a full-scale test building. Size- and time-resolved concentrations of UFP ranging from 2 to 100 nm were monitored using a scanning mobility particle sizer (SMPS). Based on the temporal evolution of the particle size distribution during the source emission period, the size-dependent source emission rate was determined using a material-balance modeling approach. The results indicate that, for a given UFP source, the source strength varies with particle size and source type. The analytical model assuming a log-normally distributed source emission rate could predict the temporal evolution of the particle size distribution with reasonable accuracy for the gas stove and the candle. Including the effect of coagulation was found to increase the estimates of source strengths by up to a factor of 8. This result implies that previous studies on indoor UFP source strengths considering only deposition and ventilation might have largely underestimated the true values of UFP source

  6. Aged particles derived from emissions of coal-fired power plants: The TERESA field results

    PubMed Central

    Kang, Choong-Min; Gupta, Tarun; Ruiz, Pablo A.; Wolfson, Jack M.; Ferguson, Stephen T.; Lawrence, Joy E.; Rohr, Annette C.; Godleski, John; Koutrakis, Petros

    2013-01-01

    The Toxicological Evaluation of Realistic Emissions Source Aerosols (TERESA) study was carried out at three US coal-fired power plants to investigate the potential toxicological effects of primary and photochemically aged (secondary) particles using in situ stack emissions. The exposure system designed successfully simulated chemical reactions that power plant emissions undergo in a plume during transport from the stack to receptor areas (e.g., urban areas). Test atmospheres developed for toxicological experiments included scenarios to simulate a sequence of atmospheric reactions that can occur in a plume: (1) primary emissions only; (2) H2SO4 aerosol from oxidation of SO2; (3) H2SO4 aerosol neutralized by gas-phase NH3; (4) neutralized H2SO4 with secondary organic aerosol (SOA) formed by the reaction of α-pinene with O3; and (5) three control scenarios excluding primary particles. The aged particle mass concentrations varied significantly from 43.8 to 257.1 μg/m3 with respect to scenario and power plant. The highest was found when oxidized aerosols were neutralized by gas-phase NH3 with added SOA. The mass concentration depended primarily on the ratio of SO2 to NOx (particularly NO) emissions, which was determined mainly by coal composition and emissions controls. Particulate sulfate (H2SO4 + neutralized sulfate) and organic carbon (OC) were major components of the aged particles with added SOA, whereas trace elements were present at very low concentrations. Physical and chemical properties of aged particles appear to be influenced by coal type, emissions controls and the particular atmospheric scenarios employed. PMID:20462390

  7. Aged particles derived from emissions of coal-fired power plants: the TERESA field results.

    PubMed

    Kang, Choong-Min; Gupta, Tarun; Ruiz, Pablo A; Wolfson, Jack M; Ferguson, Stephen T; Lawrence, Joy E; Rohr, Annette C; Godleski, John; Koutrakis, Petros

    2011-08-01

    The Toxicological Evaluation of Realistic Emissions Source Aerosols (TERESA) study was carried out at three US coal-fired power plants to investigate the potential toxicological effects of primary and photochemically aged (secondary) particles using in situ stack emissions. The exposure system designed successfully simulated chemical reactions that power plant emissions undergo in a plume during transport from the stack to receptor areas (e.g., urban areas). Test atmospheres developed for toxicological experiments included scenarios to simulate a sequence of atmospheric reactions that can occur in a plume: (1) primary emissions only; (2) H(2)SO(4) aerosol from oxidation of SO(2); (3) H(2)SO(4) aerosol neutralized by gas-phase NH(3); (4) neutralized H(2)SO(4) with secondary organic aerosol (SOA) formed by the reaction of α-pinene with O(3); and (5) three control scenarios excluding primary particles. The aged particle mass concentrations varied significantly from 43.8 to 257.1 µg/m(3) with respect to scenario and power plant. The highest was found when oxidized aerosols were neutralized by gas-phase NH(3) with added SOA. The mass concentration depended primarily on the ratio of SO(2) to NO(x) (particularly NO) emissions, which was determined mainly by coal composition and emissions controls. Particulate sulfate (H(2)SO(4) + neutralized sulfate) and organic carbon (OC) were major components of the aged particles with added SOA, whereas trace elements were present at very low concentrations. Physical and chemical properties of aged particles appear to be influenced by coal type, emissions controls and the particular atmospheric scenarios employed.

  8. Impact of Aircraft Emissions on Air Quality in the Vicinity of Airports. Volume 3. Air Quality and Emission Modeling Needs.

    DTIC Science & Technology

    1984-01-01

    designed some 10 years ago, for commercial and military facilities respec- tively, the major emphasis was on providing a user-oriented, state-of-the- art ...state of the art of modeling, there is also the clear seed to design sew versions that meet the needs and constraints of a greater uer of users...treatment. At the time of development, the computer codes incorporated state-of-the- art emissions and dispersion modeling techniques for nonreactive

  9. Measuring reactive nitrogen emissions from point sources using visible spectroscopy from aircraft.

    PubMed

    Melamed, M L; Solomon, S; Daniel, J S; Langford, A O; Portmann, R W; Ryerson, T B; Nicks, D K; McKeen, S A

    2003-02-01

    Accurate measurements of nitrogen dioxide (NO2), a key trace gas in the formation and destruction of tropospheric ozone, are important in studies of urban pollution. Nitrogen dioxide column abundances were measured during the Texas Air Quality Study 2000 using visible absorption spectroscopy from an aircraft. The method allows for quantification of the integrated total number of nitrogen dioxide molecules in the polluted atmosphere and is hence a useful tool for measuring plumes of this key trace gas. Further, we show how such remote-sensing observations can be used to obtain information on the fluxes of nitrogen dioxide into the atmosphere with unique flexibility in terms of aircraft altitude, and the height and extent of mixing of the boundary layer. Observations of nitrogen dioxide plumes downwind of power plants were used to estimate the flux of nitrogen oxide emitted from several power plants in the Houston and Dallas metropolitan areas and in North Carolina. Measurements taken over the city of Houston were also employed to infer the total flux from the city as a whole.

  10. Evaluation of Airborne Particle Emissions from Commercial Products Containing Carbon Nanotubes

    PubMed Central

    Huang, Guannan; Park, Jae Hong; Cena, Lorenzo G.; Shelton, Betsy L.; Peters, Thomas M.

    2012-01-01

    The emission of the airborne particles from epoxy resin test sticks with different CNT loadings and two commercial products were characterized while sanding with three grit sizes and three disc sander speeds. The total number concentrations, respirable mass concentrations, and particle size number/mass distributions of the emitted particles were measured using a condensation particle counter, an optical particle counter, and a scanning mobility particle sizer. The emitted particles were sampled on a polycarbonate filter and analyzed using electron microscopy. The highest number concentrations (arithmetic mean = 4670 particles/cm3) were produced with coarse sandpaper, 2% (by weight) CNT test sticks and medium disc sander speed, whereas the lowest number concentrations (arithmetic mean = 92 particles/cm3) were produced with medium sandpaper, 2% CNT test sticks and slow disc sander speed. Respirable mass concentrations were highest (arithmetic mean = 1.01 mg/m3) for fine sandpaper, 2% CNT test sticks and medium disc sander speed and lowest (arithmetic mean = 0.20 mg/m3) for medium sandpaper, 0% CNT test sticks and medium disc sander speed. For CNT-epoxy samples, airborne particles were primarily micrometer-sized epoxy cores with CNT protrusions. No free CNTs were observed in airborne samples, except for tests conducted with 4% CNT epoxy. The number concentration, mass concentration, and size distribution of airborne particles generated when products containing CNTs are sanded depends on the conditions of sanding and the characteristics of the material being sanded. PMID:23204914

  11. Ultrafine particle emission characteristics of diesel engine by on-board and test bench measurement.

    PubMed

    Huang, Cheng; Lou, Diming; Hu, Zhiyuan; Tan, Piqiang; Yao, Di; Hu, Wei; Li, Peng; Ren, Jin; Chen, Changhong

    2012-01-01

    This study investigated the emission characteristics of ultrafine particles based on test bench and on-board measurements. The bench test results showed the ultrafine particle number concentration of the diesel engine to be in the range of (0.56-8.35) x 10(8) cm(-3). The on-board measurement results illustrated that the ultrafine particles were strongly correlated with changes in real-world driving cycles. The particle number concentration was down to 2.0 x 10(6) cm(-3) and 2.7 x 10(7) cm(-3) under decelerating and idling operations and as high as 5.0 x 10(8) cm(-3) under accelerating operation. It was also indicated that the particle number measured by the two methods increased with the growth of engine load at each engine speed in both cases. The particle number presented a "U" shaped distribution with changing speed at high engine load conditions, which implies that the particle number will reach its lowest level at medium engine speeds. The particle sizes of both measurements showed single mode distributions. The peak of particle size was located at about 50-80 nm in the accumulation mode particle range. Nucleation mode particles will significantly increase at low engine load operations like idling and decelerating caused by the high concentration of unburned organic compounds.

  12. Evaluation of Airborne Particle Emissions from Commercial Products Containing Carbon Nanotubes.

    PubMed

    Huang, Guannan; Park, Jae Hong; Cena, Lorenzo G; Shelton, Betsy L; Peters, Thomas M

    2012-10-01

    The emission of the airborne particles from epoxy resin test sticks with different CNT loadings and two commercial products were characterized while sanding with three grit sizes and three disc sander speeds. The total number concentrations, respirable mass concentrations, and particle size number/mass distributions of the emitted particles were measured using a condensation particle counter, an optical particle counter, and a scanning mobility particle sizer. The emitted particles were sampled on a polycarbonate filter and analyzed using electron microscopy. The highest number concentrations (arithmetic mean = 4670 particles/cm(3)) were produced with coarse sandpaper, 2% (by weight) CNT test sticks and medium disc sander speed, whereas the lowest number concentrations (arithmetic mean = 92 particles/cm(3)) were produced with medium sandpaper, 2% CNT test sticks and slow disc sander speed. Respirable mass concentrations were highest (arithmetic mean = 1.01 mg/m(3)) for fine sandpaper, 2% CNT test sticks and medium disc sander speed and lowest (arithmetic mean = 0.20 mg/m(3)) for medium sandpaper, 0% CNT test sticks and medium disc sander speed. For CNT-epoxy samples, airborne particles were primarily micrometer-sized epoxy cores with CNT protrusions. No free CNTs were observed in airborne samples, except for tests conducted with 4% CNT epoxy. The number concentration, mass concentration, and size distribution of airborne particles generated when products containing CNTs are sanded depends on the conditions of sanding and the characteristics of the material being sanded.

  13. Isoprene in poplar emissions: effects on new particle formation and OH concentrations

    NASA Astrophysics Data System (ADS)

    Kiendler-Scharr, A.; Andres, S.; Bachner, M.; Behnke, K.; Broch, S.; Hofzumahaus, A.; Holland, F.; Kleist, E.; Mentel, T. F.; Rubach, F.; Springer, M.; Steitz, B.; Tillmann, R.; Wahner, A.; Schnitzler, J.-P.; Wildt, J.

    2011-08-01

    Stress-induced volatile organic compound (VOC) emissions from transgenic Grey poplar, modified in isoprene emission potential were used for the investigation of photochemical secondary organic aerosol (SOA) formation. Nucleation rates of up to 3600 cm-3 s-1 were observed in our experiments. In poplar, acute ozone stress induces the emission of a wide array of VOCs dominated by sesquiterpenes and aromatic VOCs. Constitutive light-dependent emission of isoprene ranged between 66 nmol m-2 s-1 in non-transgenic controls (wild type WT) and nearly zero (<0.5 nmol m-2 s-1) in isoprene emission-repressed lines (line RA22), respectively. In the presence of isoprene new particle formation was suppressed compared to non-isoprene containing VOC mixtures. Compared to isoprene/monoterpene systems emitted from other plants the suppression of nucleation by isoprene was less effective for the VOC mixture emitted from stressed poplar. This is explained by the observed high efficiency of new particle formation for emissions from stressed poplar. Direct measurements of OH in the reaction chamber revealed that the steady state concentration of OH is lower in the presence of isoprene than in the absence of isoprene, supporting the hypothesis that isoprenes' suppressing effect on nucleation is related to radical chemistry. In order to test whether isoprene contributes to SOA mass formation, fully deuterated isoprene (C5D8) was added to the stress-induced emission profile of an isoprene free poplar mutant. Mass spectral analysis showed that, despite the isoprene-induced suppression of particle formation, fractions of deuterated isoprene were incorporated into the SOA. A fractional mass yield of 2.3 % of isoprene was observed. Future emission changes due to land use and climate change may therefore affect both gas phase oxidation capacity and new particle number formation.

  14. Isoprene in poplar emissions: effects on new particle formation and OH concentrations

    NASA Astrophysics Data System (ADS)

    Kiendler-Scharr, A.; Andres, S.; Bachner, M.; Behnke, K.; Broch, S.; Hofzumahaus, A.; Holland, F.; Kleist, E.; Mentel, T. F.; Rubach, F.; Springer, M.; Steitz, B.; Tillmann, R.; Wahner, A.; Schnitzler, J.-P.; Wildt, J.

    2012-01-01

    Stress-induced volatile organic compound (VOC) emissions from transgenic Grey poplar modified in isoprene emission potential were used for the investigation of photochemical secondary organic aerosol (SOA) formation. In poplar, acute ozone stress induces the emission of a wide array of VOCs dominated by sesquiterpenes and aromatic VOCs. Constitutive light-dependent emission of isoprene ranged between 66 nmol m-2 s-1 in non-transgenic controls (wild type WT) and nearly zero (<0.5 nmol m-2 s-1) in isoprene emission-repressed plants (line RA22), respectively. Nucleation rates of up to 3600 cm-3 s-1 were observed in our experiments. In the presence of isoprene new particle formation was suppressed compared to non-isoprene containing VOC mixtures. Compared to isoprene/monoterpene systems emitted from other plants the suppression of nucleation by isoprene was less effective for the VOC mixture emitted from stressed poplar. This is explained by the observed high efficiency of new particle formation for emissions from stressed poplar. Direct measurements of OH in the reaction chamber revealed that the steady state concentration of OH is lower in the presence of isoprene than in the absence of isoprene, supporting the hypothesis that isoprenes' suppressing effect on nucleation is related to radical chemistry. In order to test whether isoprene contributes to SOA mass formation, fully deuterated isoprene (C5D8) was added to the stress-induced emission profile of an isoprene free poplar mutant. Mass spectral analysis showed that, despite the isoprene-induced suppression of particle formation, fractions of deuterated isoprene were incorporated into the SOA. A fractional mass yield of 2.3% of isoprene was observed. Future emission changes due to land use and climate change may therefore affect both gas phase oxidation capacity and new particle number formation.

  15. Influence of firebed temperature on inorganic particle emissions in a residential wood pellet boiler

    NASA Astrophysics Data System (ADS)

    Gehrig, Matthias; Jaeger, Dirk; Pelz, Stefan K.; Weissinger, Alexander; Groll, Andreas; Thorwarth, Harald; Haslinger, Walter

    2016-07-01

    The temperature-dependent release of inorganic elements is the first step of the main formation pathway of particle emissions in automatically fired biomass burners. To investigate this step, a residential pellet boiler with an underfeed-burner was equipped with a direct firebed cooling. This test setup enabled decreased firebed temperatures without affecting further parameters like air flow rates or oxygen content in the firebed. A reduction of particle emissions in PM1-fraction at activated firebed cooling was found by impactor measurement and by optical particle counter. The affected particles were found in the size range <0.3 μm and have been composed mainly of potassium chloride (KCl). The chemical analysis of PM1 and boiler ash showed no statistically significant differences due to the firebed cooling. Therefore, our results indicate that the direct firebed cooling influenced the release of potassium (K) without affecting other chemical reactions.

  16. Future European emission standards for vehicles: the importance of the UN-ECE Particle Measurement Programme.

    PubMed

    Martini, Giorgio; Giechaskiel, Barouch; Dilara, Panagiota

    2009-07-01

    Traffic-related emissions of fine particles represent one of the main sources of air pollution especially in urban areas. In particular, diesel engines are blamed as one of the main contributors for their inherent high particulate emissions. In order to reduce the impact on human health of particulate emissions from vehicles, new stricter emission standards were considered necessary for Europe. The introduction of very low particulate emission limits has required the development of an improved measurement procedure for particulate mass and a new measurement procedure for particle number. The Particle Measurement Programme (PMP) was established in 2001 on the initiative of some European states to achieve this target. The interlaboratory comparison exercise for light duty vehicles, co-managed by the Joint Research Centre (JRC) of the European Commission and the UK Department of Transport, was completed in 2007, and the results have provided the scientific basis for the new Euro 5/6 limits for particle number and particulate mass. The heavy-duty interlaboratory exercise was started in the second half of 2007 with an exploratory work carried out at the JRC and is still on-going.

  17. Indoor emissions as a primary source of airborne allergenic fungal particles in classrooms.

    PubMed

    Yamamoto, Naomichi; Hospodsky, Denina; Dannemiller, Karen C; Nazaroff, William W; Peccia, Jordan

    2015-04-21

    This study quantifies the influence of ventilation and indoor emissions on concentrations and particle sizes of airborne indoor allergenic fungal taxa and further examines geographical variability, each of which may affect personal exposures to allergenic fungi. Quantitative PCR and multiplexed DNA sequencing were employed to count and identify allergenic fungal aerosol particles indoors and outdoors in seven school classrooms in four different countries. Quantitative diversity analysis was combined with building characterization and mass balance modeling to apportion source contributions of indoor allergenic airborne fungal particles. Mass balance calculations indicate that 70% of indoor fungal aerosol particles and 80% of airborne allergenic fungal taxa were associated with indoor emissions; on average, 81% of allergenic fungi from indoor sources originated from occupant-generated emissions. Principal coordinate analysis revealed geographical variations in fungal communities among sites in China, Europe, and North America (p < 0.05, analysis of similarity), demonstrating that geography may also affect personal exposures to allergenic fungi. Indoor emissions including those released with occupancy contribute more substantially to allergenic fungal exposures in classrooms sampled than do outdoor contributions from ventilation. The results suggest that design and maintenance of buildings to control indoor emissions may enable reduced indoor inhalation exposures to fungal allergens.

  18. Analytical screening of low emissions, high performance duct burners for supersonic cruise aircraft engines

    NASA Technical Reports Server (NTRS)

    Lohmann, R. A.; Riecke, G. T.

    1977-01-01

    An analytical screening study was conducted to identify duct burner concepts capable of providing low emissions and high performance in advanced supersonic engines. Duct burner configurations ranging from current augmenter technology to advanced concepts such as premix-prevaporized burners were defined. Aerothermal and mechanical design studies provided the basis for screening these configurations using the criteria of emissions, performance, engine compatibility, cost, weight and relative risk. Technology levels derived from recently defined experimental low emissions main burners are required to achieve both low emissions and high performance goals. A configuration based on the Vorbix (Vortex burning and mixing) combustor concept was analytically determined to meet the performance goals and is consistent with the fan duct envelope of a variable cycle engine. The duct burner configuration has a moderate risk level compatible with the schedule of anticipated experimental programs.

  19. Universal decay law in charged-particle emission and exotic cluster radioactivity.

    PubMed

    Qi, C; Xu, F R; Liotta, R J; Wyss, R

    2009-08-14

    A linear universal decay formula is presented starting from the microscopic mechanism of the charged-particle emission. It relates the half-lives of monopole radioactive decays with the Q values of the outgoing particles as well as the masses and charges of the nuclei involved in the decay. This relation is found to be a generalization of the Geiger-Nuttall law in alpha radioactivity and explains well all known cluster decays. Predictions on the most likely emissions of various clusters are presented.

  20. Stimulated Light Emission and Inelastic Scattering by a Classical Linear System of Rotating Particles

    SciTech Connect

    Asenjo-Garcia, Ana; Manjavacas, Alejandro; Garcia de Abajo, F. Javier

    2011-05-27

    The rotational dynamics of particles subject to external illumination is found to produce light amplification and inelastic scattering at high rotation velocities. Light emission at frequencies shifted with respect to the incident light by twice the rotation frequency dominates over elastic scattering within a wide range of light and rotation frequencies. Remarkably, net amplification of the incident light is produced in this classical linear system via stimulated emission. Large optically induced acceleration rates are predicted in vacuum accompanied by moderate heating of the particle, thus supporting the possibility of observing these effects under extreme rotation conditions.

  1. Particle size distribution and polycyclic aromatic hydrocarbons emissions from agricultural crop residue burning.

    PubMed

    Zhang, Hefeng; Hu, Dawei; Chen, Jianmin; Ye, Xingnan; Wang, Shu Xiao; Hao, Ji Ming; Wang, Lin; Zhang, Renyi; An, Zhisheng

    2011-07-01

    Laboratory measurements were conducted to determine particle size distribution and polycyclic aromatic hydrocarbons (PAHs) emissions from the burning of rice, wheat, and corn straws, three major agricultural crop residues in China. Particle size distributions were determined by a wide-range particle spectrometer (WPS). PAHs in both the particulate and gaseous phases were simultaneously collected and analyzed by GC-MS. Particle number size distributions showed a prominent accumulation mode with peaks at 0.10, 0.15, and 0.15 μm for rice, wheat, and corn-burned aerosols, respectively. PAHs emission factors of rice, wheat, and corn straws were 5.26, 1.37, and 1.74 mg kg(-1), respectively. It was suggested that combustion with higher efficiency was characterized by smaller particle size and lower PAHs emission factors. The total PAHs emissions from the burning of three agricultural crop residues in China were estimated to be 1.09 Gg for the year 2004.

  2. Amplified light scattering and emission of silver and silver core-silica shell particles.

    PubMed

    Siiman, Olavi; Jitianu, Andrei; Bele, Marjan; Grom, Patricia; Matijević, Egon

    2007-05-01

    Side versus forward light scattergrams, and fluorescence (488 nm excitation) intensity versus particle count histograms were gathered for bare, R6G-coated, and silica-R6G-coated silver particles of 150-200 nm diameter, one-by-one by flow cytometry. Fluorescence emission intensity of the composite particles monotonically increased and then reached a plateau with greater R6G concentrations, as measured by flow cytometry. Fluorescence amplification factors of up to 3.5x10(3) were estimated by reference to measurements on core-shell particles with silica instead of silver cores. Huge surface enhanced Raman scattering (SERS) intensities, at least 10(14)-fold greater than normal Raman scattering intensities, were observed with 633 nm excitation for molecules such as rhodamine 6G (R6G) on the same single particles of silver. Although routine transmission (TEM) and scanning (SEM) electron microscopies showed gross structures of the bare and coated particles, high-resolution field emission scanning electron microscopy (FE-SEM), revealed Brownian roughness describing quantum size and larger structures on the surface of primary colloidal silver particles. These silver particles were further characterized by extinction spectra and zeta potentials. Structural and light scattering observations that are reported herein were used to tentatively propose a new hierarchical model for the mechanism of SERS.

  3. Emission rates and the personal cloud effect associated with particle release from the perihuman environment.

    PubMed

    Licina, D; Tian, Y; Nazaroff, W W

    2016-12-23

    Inhalation exposure to elevated particulate matter levels is correlated with deleterious health and well-being outcomes. Despite growing evidence that identifies humans as sources of coarse airborne particles, the extent to which personal exposures are influenced by particle releases near occupants is unknown. In a controlled chamber, we monitored airborne total particle levels with high temporal and particle-size resolution for a range of simulated occupant activities. We also sampled directly from the subject's breathing zone to characterize exposures. A material-balance model showed that a sitting occupant released 8 million particles/h in the diameter range 1-10 μm. Elevated emissions were associated with increased intensity of upper body movements and with walking. Emissions were correlated with exposure, but not linearly. The personal PM10 exposure increment above the room-average levels was 1.6-13 μg/m(3) during sitting, owing to spatial heterogeneity of particulate matter concentrations, a feature that was absent during walking. The personal cloud was more discernible among larger particles, as would be expected for shedding from skin and clothing. Manipulating papers and clothing fabric was a strong source of airborne particles. An increase in personal exposure was observed owing to particle mass exchange associated with a second room occupant.

  4. Constraining Methane Emissions from Natural Gas Production in Northeastern Pennsylvania Using Aircraft Observations and Mesoscale Modeling

    NASA Astrophysics Data System (ADS)

    Barkley, Z.; Davis, K.; Lauvaux, T.; Miles, N.; Richardson, S.; Martins, D. K.; Deng, A.; Cao, Y.; Sweeney, C.; Karion, A.; Smith, M. L.; Kort, E. A.; Schwietzke, S.

    2015-12-01

    Leaks in natural gas infrastructure release methane (CH4), a potent greenhouse gas, into the atmosphere. The estimated fugitive emission rate associated with the production phase varies greatly between studies, hindering our understanding of the natural gas energy efficiency. This study presents a new application of inverse methodology for estimating regional fugitive emission rates from natural gas production. Methane observations across the Marcellus region in northeastern Pennsylvania were obtained during a three week flight campaign in May 2015 performed by a team from the National Oceanic and Atmospheric Administration (NOAA) Global Monitoring Division and the University of Michigan. In addition to these data, CH4 observations were obtained from automobile campaigns during various periods from 2013-2015. An inventory of CH4 emissions was then created for various sources in Pennsylvania, including coalmines, enteric fermentation, industry, waste management, and unconventional and conventional wells. As a first-guess emission rate for natural gas activity, a leakage rate equal to 2% of the natural gas production was emitted at the locations of unconventional wells across PA. These emission rates were coupled to the Weather Research and Forecasting model with the chemistry module (WRF-Chem) and atmospheric CH4 concentration fields at 1km resolution were generated. Projected atmospheric enhancements from WRF-Chem were compared to observations, and the emission rate from unconventional wells was adjusted to minimize errors between observations and simulation. We show that the modeled CH4 plume structures match observed plumes downwind of unconventional wells, providing confidence in the methodology. In all cases, the fugitive emission rate was found to be lower than our first guess. In this initial emission configuration, each well has been assigned the same fugitive emission rate, which can potentially impair our ability to match the observed spatial variability

  5. Climate effects of a hypothetical regional nuclear war: Sensitivity to emission duration and particle composition

    NASA Astrophysics Data System (ADS)

    Pausata, Francesco S. R.; Lindvall, Jenny; Ekman, Annica M. L.; Svensson, Gunilla

    2016-11-01

    Here, we use a coupled atmospheric-ocean-aerosol model to investigate the plume development and climate effects of the smoke generated by fires following a regional nuclear war between emerging third-world nuclear powers. We simulate a standard scenario where 5 Tg of black carbon (BC) is emitted over 1 day in the upper troposphere-lower stratosphere. However, it is likely that the emissions from the fires ignited by bomb detonations include a substantial amount of particulate organic matter (POM) and that they last more than 1 day. We therefore test the sensitivity of the aerosol plume and climate system to the BC/POM ratio (1:3, 1:9) and to the emission length (1 day, 1 week, 1 month). We find that in general, an emission length of 1 month substantially reduces the cooling compared to the 1-day case, whereas taking into account POM emissions notably increases the cooling and the reduction of precipitation associated with the nuclear war during the first year following the detonation. Accounting for POM emissions increases the particle size in the short-emission-length scenarios (1 day/1 week), reducing the residence time of the injected particle. While the initial cooling is more intense when including POM emission, the long-lasting effects, while still large, may be less extreme compared to the BC-only case. Our study highlights that the emission altitude reached by the plume is sensitive to both the particle type emitted by the fires and the emission duration. Consequently, the climate effects of a nuclear war are strongly dependent on these parameters.

  6. Particle Acceleration, Magnetic Field Generation and Emission from Relativistic Jets and Supernova Remnants

    NASA Technical Reports Server (NTRS)

    Nishikawa, K.-I.; Hartmann, D. H.; Hardee, P.; Hededal, C.; Mizunno, Y.; Fishman, G. J.

    2006-01-01

    We performed numerical simulations of particle acceleration, magnetic field generation, and emission from shocks in order to understand the observed emission from relativistic jets and supernova remnants. The investigation involves the study of collisionless shocks, where the Weibel instability is responsible for particle acceleration as well as magnetic field generation. A 3-D relativistic particle-in-cell (RPIC) code has been used to investigate the shock processes in electron-positron plasmas. The evolution of theWeibe1 instability and its associated magnetic field generation and particle acceleration are studied with two different jet velocities (0 = 2,5 - slow, fast) corresponding to either outflows in supernova remnants or relativistic jets, such as those found in AGNs and microquasars. Slow jets have intrinsically different structures in both the generated magnetic fields and the accelerated particle spectrum. In particular, the jet head has a very weak magnetic field and the ambient electrons are strongly accelerated and dragged by the jet particles. The simulation results exhibit jitter radiation from inhomogeneous magnetic fields, generated by the Weibel instability, which has different spectral properties than standard synchrotron emission in a homogeneous magnetic field.

  7. Spatially resolving methane emissions in California: constraints from the CalNex aircraft campaign and from present (GOSAT, TES) and future (TROPOMI, geostationary) satellite observations

    NASA Astrophysics Data System (ADS)

    Wecht, K. J.; Jacob, D. J.; Sulprizio, M. P.; Santoni, G. W.; Wofsy, S. C.; Parker, R.; Bösch, H.; Worden, J.

    2014-02-01

    We apply a continental-scale inverse modeling system for North America based on the GEOS-Chem model to optimize California methane emissions at 1/2° × 2/3° horizontal resolution using atmospheric observations from the CalNex aircraft campaign (May-June 2010) and from satellites. Inversion of the CalNex data yields a best estimate for total California methane emissions of 2.86 ± 0.21 Tg yr-1, compared with 1.92 Tg yr-1 in the EDGAR v4.2 emission inventory used as a priori and 1.51 Tg yr-1 in the California Air Resources Board (CARB) inventory used for state regulations of greenhouse gas emissions. These results are consistent with a previous Lagrangian inversion of the CalNex data. Our inversion provides 12 independent pieces of information to constrain the geographical distribution of emissions within California. Attribution to individual source types indicates dominant contributions to emissions from landfills/wastewater (1.1 Tg yr-1), livestock (0.87 Tg yr-1), and gas/oil (0.64 Tg yr-1). EDGAR v4.2 underestimates emissions from livestock while CARB underestimates emissions from landfills/wastewater and gas/oil. Current satellite observations from GOSAT can constrain methane emissions in the Los Angeles Basin but are too sparse to constrain emissions quantitatively elsewhere in California (they can still be qualitatively useful to diagnose inventory biases). Los Angeles Basin emissions derived from CalNex and GOSAT inversions are 0.42 ± 0.08 and 0.31 ± 0.08, respectively. An observation system simulation experiment (OSSE) shows that the future TROPOMI satellite instrument (2015 launch) will be able to constrain California methane emissions at a detail comparable to the CalNex aircraft campaign. Geostationary satellite observations offer even greater potential for constraining methane emissions in the future.

  8. Spatially resolving methane emissions in California: constraints from the CalNex aircraft campaign and from present (GOSAT, TES) and future (TROPOMI, geostationary) satellite observations

    NASA Astrophysics Data System (ADS)

    Wecht, K. J.; Jacob, D. J.; Sulprizio, M. P.; Santoni, G. W.; Wofsy, S. C.; Parker, R.; Bösch, H.; Worden, J.

    2014-08-01

    We apply a continental-scale inverse modeling system for North America based on the GEOS-Chem model to optimize California methane emissions at 1/2° × 2/3° horizontal resolution using atmospheric observations from the CalNex aircraft campaign (May-June 2010) and from satellites. Inversion of the CalNex data yields a best estimate for total California methane emissions of 2.86 ± 0.21 Tg a-1, compared with 1.92 Tg a-1 in the EDGAR v4.2 emission inventory used as a priori and 1.51 Tg a-1 in the California Air Resources Board (CARB) inventory used for state regulations of greenhouse gas emissions. These results are consistent with a previous Lagrangian inversion of the CalNex data. Our inversion provides 12 independent pieces of information to constrain the geographical distribution of emissions within California. Attribution to individual source types indicates dominant contributions to emissions from landfills/wastewater (1.1 Tg a-1), livestock (0.87 Tg a-1), and gas/oil (0.64 Tg a-1). EDGAR v4.2 underestimates emissions from livestock, while CARB underestimates emissions from landfills/wastewater and gas/oil. Current satellite observations from GOSAT can constrain methane emissions in the Los Angeles Basin but are too sparse to constrain emissions quantitatively elsewhere in California (they can still be qualitatively useful to diagnose inventory biases). Los Angeles Basin emissions derived from CalNex and GOSAT inversions are 0.42 ± 0.08 and 0.31 ± 0.08 Tg a-1 that the future TROPOMI satellite instrument (2015 launch) will be able to constrain California methane emissions at a detail comparable to the CalNex aircraft campaign. Geostationary satellite observations offer even greater potential for constraining methane emissions in the future.

  9. A USA Commercial Flight Track Database for Upper Tropospheric Aircraft Emission Studies

    NASA Technical Reports Server (NTRS)

    Garber, Donald P.; Minnis, Patrick; Costulis, Kay P.

    2003-01-01

    A new air traffic database over the contiguous United States of America (USA) has been developed from a commercially available real-time product for 2001-2003 for all non-military flights above 25,000 ft. Both individual flight tracks and gridded spatially integrated flight legs are available. On average, approximately 24,000 high-altitude flights were recorded each day. The diurnal cycle of air traffic over the USA is characterized by a broad daytime maximum with a 0130-LT minimum and a mean day-night air traffic ratio of 2.4. Each week, the air traffic typically peaks on Thursday and drops to a low Saturday with a range of 18%. Flight density is greatest during late summer and least during winter. The database records the disruption of air traffic after the air traffic shutdown during September 2001. The dataset should be valuable for realistically simulating the atmospheric effects of aircraft in the upper troposphere.

  10. Late-time particle emission from laser-produced graphite plasma

    SciTech Connect

    Harilal, S. S.; Hassanein, A.; Polek, M.

    2011-09-01

    We report a late-time ''fireworks-like'' particle emission from laser-produced graphite plasma during its evolution. Plasmas were produced using graphite targets excited with 1064 nm Nd: yttrium aluminum garnet (YAG) laser in vacuum. The time evolution of graphite plasma was investigated using fast gated imaging and visible emission spectroscopy. The emission dynamics of plasma is rapidly changing with time and the delayed firework-like emission from the graphite target followed a black-body curve. Our studies indicated that such firework-like emission is strongly depended on target material properties and explained due to material spallation caused by overheating the trapped gases through thermal diffusion along the layer structures of graphite.

  11. Ethanol Blends and Engine Operating Strategy Effects on Light-Duty Spark-Ignition Engine Particle Emissions

    SciTech Connect

    Szybist, James P; Youngquist, Adam D; Barone, Teresa L; Storey, John Morse; Moore, Wayne; Foster, Matthew; Confer, Keith

    2011-01-01

    Spark ignition (SI) engines with direct injection (DI) fueling can improve fuel economy and vehicle power beyond that of port fuel injection (PFI). Despite this distinct advantage, DI fueling often increases particle emissions such that SI exhaust may be subject to future particle emissions regulations. Challenges in controlling particle emissions arise as engines encounter varied fuel composition such as intermediate ethanol blends. Furthermore, modern engines are operated using unconventional breathing strategies with advanced cam-based variable valve actuation systems. In this study, we investigate particle emissions from a multi-cylinder DI engine operated with three different breathing strategies, fueling strategies and fuels. The breathing strategies are conventional throttled operation, early intake valve closing (EIVC) and late intake valve closing (LIVC); the fueling strategies are single injection DI (sDI), multi-injection DI (mDI), and PFI; and the fuels are emissions certification gasoline, E20 and E85. The results indicate the dominant factor influencing particle number concentration emissions for the sDI and mDI strategies is the fuel injection timing. Overly advanced injection timing results in particle formation due to fuel spray impingement on the piston, and overly retarded injection timing results in particle formation due to poor fuel and air mixing. In addition, fuel type has a significant effect on particle emissions for the DI fueling strategies. Gasoline and E20 fuels generate comparable levels of particle emissions, but E85 produces dramatically lower particle number concentration. The particle emissions for E85 are near the detection limit for the FSN instrument, and particle number emissions are one to two orders of magnitude lower for E85 relative to gasoline and E20. We found PFI fueling produces very low levels of particle emissions under all conditions and is much less sensitive to engine breathing strategy and fuel type than the DI

  12. Particle number emissions of motor traffic derived from street canyon measurements in a Central European city

    NASA Astrophysics Data System (ADS)

    Klose, S.; Birmili, W.; Voigtländer, J.; Tuch, T.; Wehner, B.; Wiedensohler, A.; Ketzel, M.

    2009-02-01

    A biennial dataset of ambient particle number size distributions (diameter range 4-800 nm) collected in urban air in Leipzig, Germany, was analysed with respect to the influence of traffic emissions. Size distributions were sampled continuously in 2005 and 2006 inside a street canyon trafficked by ca. 10 000 motor vehicles per day, and at a background reference site distant at 1.5 km. Auto-correlation analysis showed that the impact of fresh traffic emissions could be seen most intensely below particle sizes of 60 nm. The traffic-induced concentration increment at roadside was estimated by subtracting the urban background values from the street canyon measurement. To describe the variable dispersion conditions inside the street canyon, micro-meteorological dilution factors were calculated using the Operational Street Pollution Model (OSPM), driven by above-roof wind speed and wind direction observations. The roadside increment concentrations, dilution factor, and real-time traffic counts were used to calculate vehicle emission factors (aerosol source rates) that are representative of the prevailing driving conditions, i.e. stop-and-go traffic including episodes of fluent traffic flow at speeds up to 40 km h-1. The size spectrum of traffic-derived particles was essentially bimodal - with mode diameters around 12 and 100 nm, while statistical analysis suggested that the emitted number concentration varied with time of day, wind direction, particle size and fleet properties. Significantly, the particle number emissions depended on ambient temperature, ranging between 4.8 (±1.8) and 7.8 (±2.9).1014 p. veh-1 km-1 in summer and winter, respectively. A separation of vehicle types according to vehicle length suggested that lorry-like vehicles emit about 80 times more particle number than passenger car-like vehicles. Using nitrogen oxide (NOx) measurements, specific total particle number emissions of 338 p. (pg NOx)-1 were inferred. The calculated traffic emission factors

  13. Screening analysis and selection of emission reduction concepts for intermittent combustion aircraft engines

    NASA Technical Reports Server (NTRS)

    Rezy, B. J.; Meyers, J. E.; Tucker, J. R.; Stuckas, S. J.

    1976-01-01

    An analysis was conducted to screen, evaluate, and select three engine exhaust emission reduction concepts from a group of 14 candidate alternatives. A comprehensive literature search was conducted to survey the emission reduction technology state-of-the-art and establish contact with firms working on intermittent combustion engine development and pollution reduction problems. Concept development, advantages, disadvantages, and expected emission reduction responses are stated. A set of cost effectiveness criteria was developed, appraised for relative importance, and traded off against each concept so that its merit could be determined. A decision model was used to aid the evaluators in managing the criteria, making consistent judgements, calculating merit scores, and ranking the concepts. An Improved Fuel Injection System, Improved Cooling Combustion Chamber, and a Variable Timing Ignition System were recommended to NASA for approval and further concept development. An alternate concept, Air Injection, was also recommended.

  14. Blue Emission Peak of GeO{sub 2} Particles Grown Using Thermal Evaporation

    SciTech Connect

    Sulieman, Kamal Mahir; Jumidali, M. M.; Hashim, M. R.

    2010-07-07

    In this paper we report a simple thermal evaporation technique (horizontal tube furnace) to grow large quantities of GeO{sub 2} particles with diameters ranging from tens of nanometer to 500 nm on n-type (100) Si substrate free of catalyst. The particles were grown at temperature about 1000 degree sign C for 2 hrs and characterized by scanning electron microscopy (SEM), X-Ray diffraction (XRD), energy-dispersive X-ray spectroscopy (EDX) and photoluminescence (PL) spectroscopy. The photoluminescence spectrum reveals several emission peaks around 400 nm at room temperature. Raman measurement also measured at room temperature for this GeO{sub 2} particles.

  15. Plasma precipitation and neutral particle emission at Ganymede

    NASA Astrophysics Data System (ADS)

    Massetti, S.; Milillo, A.; Mura, A.; Orsini, S.; Plainaki, C.; Mangano, V.

    2012-04-01

    Ganymede, the largest moon of Jupiter is characterized by a tiny magnetosphere produced by an intrinsic magnetic moment; it is linked to the Jovian magnetosphere and embedded in its energetic plasma environment. In addition, since the plasma co-rotating with Jupiter impinges on Ganymede trailing side at subsonic speed, there is no bow-shock formation. Here we present preliminary results of Monte Carlo simulations aimed to evaluate the expected ion precipitation onto the polar caps of Ganymede, by means of the magnetic and electric fields derived by a global magnetohydrodynamic (MHD) model that realistically describe Ganymede's magnetospheric environment. We discuss precipitation pattern differences between the simulated ion species (H+, O+ and S+) at different energies in the range 10-100 keV. Plasma precipitating onto the surface of Ganymede modifies it both physically (via ion sputtering) and chemically (via radiolysis). Directly sputtered H2O molecules as well as products of H2O decomposition, that may recombine and produce diverse molecules, such as O2 and H2 are released. The yields of these processes have been estimated by means of accurate function that includes the dependence of the release on impacting ion species and energy as well as on the moon's surface temperature. In this study we attempted to isolate the temperature dependent part of this yield function and to assign it exclusively to the chemical processes taking place on ice and to the subsequent release of new molecules. In this way we make a rough preliminary distinction between the sputtering and radiolysis exospheric contributions. In our estimations we take into account also the energy spectra of precipitating plasma. A MonteCarlo model has been used to simulate the neutral density of escaping particles. Here we present results in terms of density and fluxes.

  16. Probing Aircraft Flight Test Hazard Mitigation for the Alternative Fuel Effects on Contrails and Cruise Emissions (ACCESS) Research Team . Volume 2; Appendices

    NASA Technical Reports Server (NTRS)

    Kelly, Michael J.

    2013-01-01

    The Alternative Fuel Effects on Contrails and Cruise Emissions (ACCESS) Project Integration Manager requested in July 2012 that the NASA Engineering and Safety Center (NESC) form a team to independently assess aircraft structural failure hazards associated with the ACCESS experiment and to identify potential flight test hazard mitigations to ensure flight safety. The ACCESS Project Integration Manager subsequently requested that the assessment scope be focused predominantly on structural failure risks to the aircraft empennage (horizontal and vertical tail). This report contains the Appendices to Volume I.

  17. TOTAL PARTICLE, SULFATE, AND ACIDIC AEROSOL EMISSIONS FROM KEROSENE SPACE HEATERS

    EPA Science Inventory

    Chamber studies were conducted on four unvented kerosene space heaters to assess emissions of total particle, sulfate, and acidic aerosol. The heaters tested represented four burner designs currently in use by the public. Kerosene space heaters are a potential source of fine part...

  18. CHARACTERIZATION OF THE FINE PARTICLE AND GASEOUS EMISSIONS DURING SCHOOL BUS IDLING

    EPA Science Inventory

    The particulate matter (PM) and gaseous emissions from six diesel school buses were determined over a simulated idling period typical of schools in the northeastern U.S. Testing was conducted for both continuous idle and hot restart conditions using particle and gas analyzers. Th...

  19. Particle size distribution characteristics of cotton gin first stage lint cleaning system total particulate emissions

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This report is part of a project to characterize cotton gin emissions from the standpoint of total particulate stack sampling and particle size analyses. In 2006, EPA published a more stringent standard for particulate matter with nominal diameter less than or equal to 2.5 µm (PM2.5). This created a...

  20. Combined mote system particulate emission factors for cotton gins: Particle size distribution characteristics

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This report is part of a project to characterize cotton gin emissions from the standpoint of total particulate stack sampling and particle size analyses. In 2013, the Environmental Protection Agency (EPA) published a more stringent standard for particulate matter with nominal diameter less than or e...

  1. Master trash system particulate emission factors for cotton gins: Particle size distribution characteristics

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This report is part of a project to characterize cotton gin emissions from the standpoint of total particulate stack sampling and particle size analyses. In 2013, U.S. Environmental Protection Agency (EPA) published a more stringent standard for particulate matter with nominal diameter less than or ...

  2. Particle size distribution characteristics of cotton gin combined mote system total particulate emissions

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This report is part of a project to characterize cotton gin emissions from the standpoint of total particulate stack sampling and particle size analyses. In 2013, EPA published a more stringent standard for particulate matter with nominal diameter less than or equal to 2.5 µm (PM2.5). This created a...

  3. Overflow system particulate emission factors for cotton gins: Particle size distribution characteristics

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This report is part of a project to characterize cotton gin emissions from the standpoint of total particulate stack sampling and particle size analyses. In 2013, the U.S. Environmental Protection Agency (EPA) published a more stringent standard for particulate matter with nominal diameter less than...

  4. First stage lint cleaning system particulate emission factors for cotton gins: Particle size distribution characteristics

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This report is part of a project to characterize cotton gin emissions from the standpoint of total particulate stack sampling and particle size analyses. In 2006, Environmental Protection Agency (EPA) published a more stringent standard for particulate matter with nominal diameter less than or equal...

  5. Particle size distribution characteristics of cotton gin unloading system total particulate emissions

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This report is part of a project to characterize cotton gin emissions from the standpoint of total particulate stack sampling and particle size analyses. In 2013, EPA published a more stringent standard for particulate matter with nominal diameter less than or equal to 2.5 µm (PM2.5). This created a...

  6. Particle size distribution characteristics of cotton gin second stage mote system total particulate emissions

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This report is part of a project to characterize cotton gin emissions from the standpoint of total particulate stack sampling and particle size analyses. In 2013, EPA published a more stringent standard for particulate matter with nominal diameter less than or equal to 2.5 µm (PM2.5). This created a...

  7. Particle size distribution characteristics of cotton gin second stage lint cleaning system total particulate emissions

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This report is part of a project to characterize cotton gin emissions from the standpoint of total particulate stack sampling and particle size analyses. In 2013, EPA published a more stringent standard for particulate matter with nominal diameter less than or equal to 2.5 µm (PM2.5). This created a...

  8. Combined lint cleaning system particulate emission factors for cotton gins: Particle size distribution characteristics

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This report is part of a project to characterize cotton gin emissions from the standpoint of total particulate stack sampling and particle size analyses. In 2013, the Environmental Protection Agency (EPA) published a more stringent standard for particulate matter with nominal diameter less than or e...

  9. Particle size distribution characteristics of cotton gin mote trash system total particulate emissions

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This report is part of a project to characterize cotton gin emissions from the standpoint of total particulate stack sampling and particle size analyses. In 2013, EPA published a more stringent standard for particulate matter with nominal diameter less than or equal to 2.5 µm (PM2.5). This created a...

  10. Second stage mote system particulate emission factors for cotton gins: Particle size distribution characteristics

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This report is part of a project to characterize cotton gin emissions from the standpoint of total particulate stack sampling and particle size analyses. In 2013, Environmental Protection Agency (EPA) published a more stringent standard for particulate matter with nominal diameter less than or equal...

  11. Second stage lint cleaning system particulate emission factors for cotton gins: Particle size distribution characteristics

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This report is part of a project to characterize cotton gin emissions from the standpoint of total particulate stack sampling and particle size analyses. In 2013, Environmental Protection Agency (EPA) published a more stringent standard for particulate matter with nominal diameter less than or equal...

  12. Mote cleaner system particulate emission factors for cotton gins: Particle size distribution characteristics

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This report is part of a project to characterize cotton gin emissions from the standpoint of total particulate stack sampling and particle size analyses. In 2013, U.S. Environmental Protection Agency (EPA) published a more stringent standard for particulate matter with nominal diameter less than or ...

  13. Mote trash system particulate emission factors for cotton gins: Particle size distribution characteristics

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This report is part of a project to characterize cotton gin emissions from the standpoint of total particulate stack sampling and particle size analyses. In 2013, the U.S. Environmental Protection Agency (EPA) published a more stringent standard for particulate matter with nominal diameter less than...

  14. Particle size distribution characteristics of cotton gin combined lint cleaning system total particulate emissions

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This report is part of a project to characterize cotton gin emissions from the standpoint of total particulate stack sampling and particle size analyses. In 2013, EPA published a more stringent standard for particulate matter with nominal diameter less than or equal to 2.5 µm (PM2.5). This created a...

  15. Mote cyclone robber system particulate emission factors for cotton gins: Particle size distribution characteristics

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This report is part of a project to characterize cotton gin emissions from the standpoint of total particulate stack sampling and particle size analyses. In 2013, the U.S. Environmental Protection Agency (EPA) published a more stringent standard for particulate matter with nominal diameter less than...

  16. Particle size distribution characteristics of cotton gin overflow system total particulate emissions

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This report is part of a project to characterize cotton gin emissions from the standpoint of total particulate stack sampling and particle size analyses. In 2013, EPA published a more stringent standard for particulate matter with nominal diameter less than or equal to 2.5 µm (PM2.5). This created a...

  17. Cyclone robber system particulate emission factors for cotton gins: Particle size distribution characteristics

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This report is part of a project to characterize cotton gin emissions from the standpoint of total particulate stack sampling and particle size analyses. In 2013, U.S. Environmental Protection Agency (EPA) published a more stringent standard for particulate matter with nominal diameter less than or ...

  18. Particle size distribution characteristics of cotton gin master trash system total particulate emissions

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This report is part of a project to characterize cotton gin emissions from the standpoint of total particulate stack sampling and particle size analyses. In 2013, EPA published a more stringent standard for particulate matter with nominal diameter less than or equal to 2.5 µm (PM2.5). This created a...

  19. First stage mote system particulate emission factors for cotton gins: Particle size distribution characteristics

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This report is part of a project to characterize cotton gin emissions from the standpoint of total particulate stack sampling and particle size analyses. In 2013, the Environmental Protection Agency (EPA) published a more stringent standard for particulate matter with nominal diameter less than or e...

  20. Particle size distribution characteristics of cotton gin mote cleaner system total particulate emissions

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This report is part of a project to characterize cotton gin emissions from the standpoint of total particulate stack sampling and particle size analyses. In 2013, EPA published a more stringent standard for particulate matter with nominal diameter less than or equal to 2.5 µm (PM2.5). This created a...

  1. Unloading system particulate emission factors for cotton gins: Particle size distribution characteristics

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This report is part of a project to characterize cotton gin emissions from the standpoint of total particulate stack sampling and particle size analyses. In 2013, the U.S. Environmental Protection Agency (EPA) published a more stringent standard for particulate matter with nominal diameter less than...

  2. Particle size distribution characteristics of cotton gin first stage mote system total particulate emissions

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This report is part of a project to characterize cotton gin emissions from the standpoint of total particulate stack sampling and particle size analyses. In 2013, EPA published a more stringent standard for particulate matter with nominal diameter less than or equal to 2.5 µm (PM2.5). This created a...

  3. 14th International Conference on Particle Induced X-ray Emission ("PIXE 2015")

    NASA Astrophysics Data System (ADS)

    Przybyłowicz, Wojciech Józef; Pineda-Vargas, Carlos

    2015-11-01

    This special issue of Nuclear Instruments and Methods in Physics Research B contains the proceedings of the 14th International Conference on Particle Induced X-ray Emission ("PIXE 2015") that was held in Somerset West (South Africa) from 25th February to 3rd March 2015.

  4. Emission and Size Distribution of Particle-bound Polycyclic Aromatic Hydrocarbons from Residential Wood Combustion

    PubMed Central

    Shen, Guofeng; Wei, Siye; Zhang, Yanyan; Wang, Bin; Wang, Rong; Shen, Huizhong; Li, Wei; Huang, Ye; Chen, Yuanchen; Chen, Han; Tao, Shu

    2015-01-01

    Emissions and size distributions of 28 particle-bound polycyclic aromatic hydrocarbons (PAHs) from residential combustion of 19 fuels in a domestic cooking stove in rural China were studied. Measured emission factors of total PAHs were 1.79±1.55, 12.1±9.1, and 5.36±4.46 mg/kg for fuel wood, brushwood, and bamboo, respectively. Approximate 86.7, 65.0, and 79.7% of the PAHs were associated with fine particulate matter with size less than 2.1 µm for these three types of fuels. Statistically significant difference in emission factors and size distributions of particle-bound PAHs between fuel wood and brushwood was observed, with the former had lower emission factors but more PAHs in finer PM. Mass fraction of the fine particles associated PAHs was found to be positively correlated with fuel density and moisture, and negatively correlated with combustion efficiency. Low and high molecular weight PAHs segregated into the coarse and fine PM, respectively. The high accumulation tendency of the PAHs from residential wood combustion in fine particles implies strong adverse health impact. PMID:25678760

  5. COMPARATIVE TOXICITY OF DIFFERENT EMISSION PARTICLES IN MURINE PULMONARY EPITHELIAL CELLS AND MACROPHAGES

    EPA Science Inventory

    Comparative Toxicity of Different Emission Particles in Murine Pulmonary Epithelial Cells and Macrophages. T Stevens1, M Daniels2, P Singh2, M I Gilmour2. 1 UNC, Chapel Hill 27599 2Experimental Toxicology Division, NHEERL, RTP, NC 27711

    Epidemiological studies have shown ...

  6. Battery condenser system particulate emission factors for cotton gins: Particle size distribution characteristics

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This report is part of a project to characterize cotton gin emissions from the standpoint of total particulate stack sampling and particle size analyses. In 2013, the Environmental Protection Agency (EPA) published a more stringent standard for particulate matter with nominal diameter less than or e...

  7. Particle size distribution characteristics of cotton gin battery condenser system total particulate emissions

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This report is part of a project to characterize cotton gin emissions from the standpoint of total particulate stack sampling and particle size analyses. In 2013, EPA published a more stringent standard for particulate matter with nominal diameter less than or equal to 2.5 µm (PM2.5). This created a...

  8. Particle size distribution characteristics of cotton gin mote cyclone robber system total particulate emissions

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This report is part of a project to characterize cotton gin emissions from the standpoint of total particulate stack sampling and particle size analyses. In 2013, EPA published a more stringent standard for particulate matter with nominal diameter less than or equal to 2.5 µm (PM2.5). This created a...

  9. Particle size distribution characteristics of cotton gin cyclone robber system total particulate emissions

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This report is part of a project to characterize cotton gin emissions from the standpoint of total particulate stack sampling and particle size analyses. In 2013, EPA published a more stringent standard for particulate matter with nominal diameter less than or equal to 2.5 µm (PM2.5). This created a...

  10. Size Differentiation Of A Continuous Stream Of Particles Using Acoustic Emissions

    NASA Astrophysics Data System (ADS)

    Nsugbe, E.; Starr, A.; Foote, P.; Ruiz-Carcel, C.; Jennions, I.

    2016-11-01

    Procter and Gamble (P&G) require an online system that can monitor the particle size distribution of their washing powder mixing process. This would enable the process to take a closed loop form which would enable process optimisation to take place in real time. Acoustic Emission (AE) was selected as the sensing method due to its non-invasive nature and primary sensitivity to frequencies which particle events emanate. This work details the results of the first experiment carried out in this research project. This experiment involved the use of AE to distinguish between the sizes of sieved polyethylene particle (53-250microns) and glass beads (150-600microns) which were dispensed on a target plate using a funnel. By conducting a threshold analysis of the impact peaks in the signal, the sizes of the particles could be distinguished and a signal feature was found which could be directly linked to the sizes of the particles.

  11. 78 FR 63015 - Exhaust Emissions Standards for New Aircraft Gas Turbine Engines and Identification Plate for...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-10-23

    ... kilonewtons (kN) (76 FR 45012). The EPA also proposed adopting the gas turbine engine test procedures of the... 18, 2012 (77 FR 36342), and was effective July 18, 2012. On December 31, 2012, the FAA published a final rule with a request for comments (77 FR 76842) adopting the EPA's new emissions standards in...

  12. 78 FR 63017 - Exhaust Emissions Standards for New Aircraft Gas Turbine Engines and Identification Plate for...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-10-23

    ... engines with rated thrusts greater than 26.7 kilonewtons (kN) (76 FR 45012). The EPA also proposed...). The final rule adopting these proposals was published on June 18, 2012 (77 FR 36342), and was... (77 FR 76842) adopting the EPA's new emissions standards in part 34. Although the EPA's NPRM...

  13. Aircraft-Based Estimate of Total Methane Emissions from the Barnett Shale Region.

    PubMed

    Karion, Anna; Sweeney, Colm; Kort, Eric A; Shepson, Paul B; Brewer, Alan; Cambaliza, Maria; Conley, Stephen A; Davis, Ken; Deng, Aijun; Hardesty, Mike; Herndon, Scott C; Lauvaux, Thomas; Lavoie, Tegan; Lyon, David; Newberger, Tim; Pétron, Gabrielle; Rella, Chris; Smith, Mackenzie; Wolter, Sonja; Yacovitch, Tara I; Tans, Pieter

    2015-07-07

    We present estimates of regional methane (CH4) emissions from oil and natural gas operations in the Barnett Shale, Texas, using airborne atmospheric measurements. Using a mass balance approach on eight different flight days in March and October 2013, the total CH4 emissions for the region are estimated to be 76 ± 13 × 10(3) kg hr(-1) (equivalent to 0.66 ± 0.11 Tg CH4 yr(-1); 95% confidence interval (CI)). We estimate that 60 ± 11 × 10(3) kg CH4 hr(-1) (95% CI) are emitted by natural gas and oil operations, including production, processing, and distribution in the urban areas of Dallas and Fort Worth. This estimate agrees with the U.S. Environmental Protection Agency (EPA) estimate for nationwide CH4 emissions from the natural gas sector when scaled by natural gas production, but it is higher than emissions reported by the EDGAR inventory or by industry to EPA's Greenhouse Gas Reporting Program. This study is the first to show consistency between mass balance results on so many different days and in two different seasons, enabling better quantification of the related uncertainty. The Barnett is one of the largest production basins in the United States, with 8% of total U.S. natural gas production, and thus, our results represent a crucial step toward determining the greenhouse gas footprint of U.S. onshore natural gas production.

  14. EMISSION MEASUREMENTS OF PARTICLE MASS AND SIZE EMISSION PROFILES FROM CONSTRUCTION ACTIVITIES

    EPA Science Inventory

    The report gives results from field tests that characterize the amount and size distribution of particulate matter (PM) emissions from operations at construction sites. Of particular interest is the movement of earth by scraper loading and unloading, grading, transit vehicular m...

  15. Morphology and Optical Properties of Black-Carbon Particles Relevant to Engine Emissions

    NASA Astrophysics Data System (ADS)

    Michelsen, H. A.; Bambha, R.; Dansson, M. A.; Schrader, P. E.

    2013-12-01

    Black-carbon particles are believed to have a large influence on climate through direct radiative forcing, reduction of surface albedo of snow and ice in the cryosphere, and interaction with clouds. The optical properties and morphology of atmospheric particles containing black carbon are uncertain, and characterization of black carbon resulting from engines emissions is needed. Refractory black-carbon particles found in the atmosphere are often coated with unburned fuel, sulfuric acid, water, ash, and other combustion by-products and atmospheric constituents. Coatings can alter the optical and physical properties of the particles and therefore change their optical properties and cloud interactions. Details of particle morphology and coating state can also have important effects on the interpretation of optical diagnostics. A more complete understanding of how coatings affect extinction, absorption, and incandescence measurements is needed before these techniques can be applied reliably to a wide range of particles. We have investigated the effects of coatings on the optical and physical properties of combustion-generated black-carbon particles using a range of standard particle diagnostics, extinction, and time-resolved laser-induced incandescence (LII) measurements. Particles were generated in a co-flow diffusion flame, extracted, cooled, and coated with oleic acid. The diffusion flame produces highly dendritic soot aggregates with similar properties to those produced in diesel engines, diffusion flames, and most natural combustion processes. A thermodenuder was used to remove the coating. A scanning mobility particle sizer (SMPS) was used to monitor aggregate sizes; a centrifugal particle mass analyzer (CPMA) was used to measure coating mass fractions, and transmission electron microscopy (TEM) was used to characterize particle morphologies. The results demonstrate important differences in optical measurements between coated and uncoated particles.

  16. Selective catalytic reduction operation with heavy fuel oil: NOx, NH3, and particle emissions.

    PubMed

    Lehtoranta, Kati; Vesala, Hannu; Koponen, Päivi; Korhonen, Satu

    2015-04-07

    To meet stringent NOx emission limits, selective catalytic reduction (SCR) is increasingly utilized in ships, likely also in combination with low-priced higher sulfur level fuels. In this study, the performance of SCR was studied by utilizing NOx, NH3, and particle measurements. Urea decomposition was studied with ammonia and isocyanic acid measurements and was found to be more effective with heavy fuel oil (HFO) than with light fuel oil. This is suggested to be explained by the metals found in HFO contributing to metal oxide particles catalyzing the hydrolysis reaction prior to SCR. At the exhaust temperature of 340 °C NOx reduction was 85-90%, while at lower temperatures the efficiency decreased. By increasing the catalyst loading, the low temperature behavior of the SCR was enhanced. The drawback of this, however, was the tendency of particle emissions (sulfate) to increase at higher temperatures with higher loaded catalysts. The particle size distribution results showed high amounts of nanoparticles (in 25-30 nm size), the formation of which SCR either increased or decreased. The findings of this work provide a better understanding of the usage of SCR in combination with a higher sulfur level fuel and also of ship particle emissions, which are a growing concern.

  17. Comparison of improved Aura Tropospheric Emission Spectrometer (TES) CO2 with HIPPO and SGP aircraft profile measurements

    SciTech Connect

    Kulawik, S. S.; Worden, J. R.; Wofsy, S. C.; Biraud, S. C.; Nassar, R.; Jones, D. B. A.; Olsen, E. T.; Osterman, and the TES and HIPPO teams, G. B.

    2012-01-01

    Comparisons are made between mid-tropospheric Tropospheric Emission Spectrometer (TES) carbon dioxide (CO{sub 2}) satellite measurements and ocean profiles from three Hiaper Pole-to-Pole Observations (HIPPO) campaigns and land aircraft profiles from the United States Southern Great Plains (SGP) Atmospheric Radiation Measurement (ARM) site over a 4-yr period. These comparisons are used to characterize the bias in the TES CO{sub 2} estimates and to assess whether calculated and actual uncertainties and sensitivities are consistent. The HIPPO dataset is one of the few datasets spanning the altitude range where TES CO{sub 2} estimates are sensitive, which is especially important for characterization of biases. We find that TES CO{sub 2} estimates capture the seasonal and latitudinal gradients observed by HIPPO CO{sub 2} measurements; actual errors range from 0.8–1.2 ppm, depending on the campaign, and are approximately 1.4 times larger than the predicted errors. The bias of TES versus HIPPO is within 0.85 ppm for each of the 3 campaigns; however several of the sub-tropical TES CO{sub 2} estimates are lower than expected based on the calculated errors. Comparisons of aircraft flask profiles, which are measured from the surface to 5 km, to TES CO{sub 2} at the SGP ARM site show good agreement with an overall bias of 0.1 ppm and rms of 1.0 ppm. We also find that the predicted sensitivity of the TES CO{sub 2} estimates is too high, which results from using a multi-step retrieval for CO{sub 2} and temperature. We find that the averaging kernel in the TES product corrected by a pressure-dependent factor accurately reflects the sensitivity of the TES CO{sub 2} product.

  18. Particle and light fragment emission in peripheral heavy ion collisions at Fermi energies

    SciTech Connect

    Piantelli, S.; Maurenzig, P. R.; Olmi, A.; Bardelli, L.; Bartoli, A.; Bini, M.; Casini, G.; Coppi, C.; Mangiarotti, A.; Pasquali, G.; Poggi, G.; Stefanini, A. A.; Taccetti, N.; Vanzi, E.

    2006-09-15

    A systematic investigation of the average multiplicities of light charged particles and intermediate mass fragments emitted in peripheral and semiperipheral collisions is presented as a function of the beam energy, violence of the collision, and mass of the system. The data have been collected with the FIASCO setup in the reactions {sup 93}Nb+{sup 93}Nb at (17,23,30,38)A MeV and {sup 116}Sn+{sup 116}Sn at (30,38)A MeV. The midvelocity emission has been separated from the emission of the projectile-like fragment. This last component appears to be compatible with an evaporation from an equilibrated source at normal density, as described by the statistical code GEMINI at the appropriate excitation energy. On the contrary, the midvelocity emission presents remarkable differences in both the dependence of the multiplicities on the energy deposited in the midvelocity region and the isotopic composition of the emitted light charged particles.

  19. Size-resolved particle number emission patterns under real-world driving conditions using positive matrix factorization.

    PubMed

    Domínguez-Sáez, Aida; Viana, Mar; Barrios, Carmen C; Rubio, Jose R; Amato, Fulvio; Pujadas, Manuel; Querol, Xavier

    2012-10-16

    A novel on-board system was tested to characterize size-resolved particle number emission patterns under real-world driving conditions, running in a EURO4 diesel vehicle and in a typical urban circuit in Madrid (Spain). Emission profiles were determined as a function of driving conditions. Source apportionment by Positive Matrix Factorization (PMF) was carried out to interpret the real-world driving conditions. Three emission patterns were identified: (F1) cruise conditions, with medium-high speeds, contributing in this circuit with 60% of total particle number and a particle size distribution dominated by particles >52 nm and around 60 nm; (F2) transient conditions, stop-and-go conditions at medium-high speed, contributing with 25% of the particle number and mainly emitting particles in the nucleation mode; and (F3) creep-idle conditions, representing traffic congestion and frequent idling periods, contributing with 14% to the total particle number and with particles in the nucleation mode (<29.4 nm) and around 98 nm. We suggest potential approaches to reduce particle number emissions depending on particle size and driving conditions. Differences between real-world emission patterns and regulatory cycles (NEDC) are also presented, which evidence that detecting particle number emissions <40 nm is only possible under real-world driving conditions.

  20. Quantifying Energetic Particle Precipitation using the Array for Broadband Observations of VLF/ELF Emissions (ABOVE)

    NASA Astrophysics Data System (ADS)

    Cully, C. M.

    2015-12-01

    The Array for Broadband Observations of VLF/ELF Emissions (ABOVE) is a network of instruments deployed across Western Canada to monitor electromagnetic emissions from 200 Hz to 75 kHz. By observing the amplitude and phase of artificial ground-based transmitters in this band, we monitor changes in lower D layer ionization caused by energetic particle precipitation. We discuss numerical modeling and sensitivity analyses that enable us to use ABOVE data to quantify energetic particle precipitation over Western Canada. We then apply this technique to precipitation events, comparing our preliminary results with in-situ and ground-based observations. We conclude that ABOVE offers a large-scale perspective on the problem of acceleration and loss of radiation belt particles that complements the detailed in-situ measurements from the Van Allen Probes, Themis, and other satellite missions.

  1. Electron microscopic study of soot particulate matter emissions from aircraft turbine engines.

    PubMed

    Liati, Anthi; Brem, Benjamin T; Durdina, Lukas; Vögtli, Melanie; Dasilva, Yadira Arroyo Rojas; Eggenschwiler, Panayotis Dimopoulos; Wang, Jing

    2014-09-16

    The microscopic characteristics of soot particulate matter (PM) in gas turbine exhaust are critical for an accurate assessment of the potential impacts of the aviation industry on the environment and human health. The morphology and internal structure of soot particles emitted from a CFM 56-7B26/3 turbofan engine were analyzed in an electron microscopic study, down to the nanoscale, for ∼ 100%, ∼ 65%, and ∼ 7% static engine thrust as a proxy for takeoff, cruising, and taxiing, respectively. Sampling was performed directly on transmission electron microscopy (TEM) grids with a state-of-the-art sampling system designed for nonvolatile particulate matter. The electron microscopy results reveal that ∼ 100% thrust produces the highest amount of soot, the highest soot particle volume, and the largest and most crystalline primary soot particles with the lowest oxidative reactivity. The opposite is the case for soot produced during taxiing, where primary soot particles are smallest and most reactive and the soot amount and volume are lowest. The microscopic characteristics of cruising condition soot resemble the ones of the ∼ 100% thrust conditions, but they are more moderate. Real time online measurements of number and mass concentration show also a clear correlation with engine thrust level, comparable with the TEM study. The results of the present work, in particular the small size of primary soot particles present in the exhaust (modes of 24, 20, and 13 nm in diameter for ∼ 100%, ∼ 65% and ∼ 7% engine thrust, respectively) could be a concern for human health and the environment and merit further study. This work further emphasizes the significance of the detailed morphological characteristics of soot for assessing environmental impacts.

  2. Self-consistent particle-in-cell simulations of fundamental and harmonic radio plasma emission mechanisms

    NASA Astrophysics Data System (ADS)

    Tsiklauri, D.; Thurgood, J. O.

    2015-12-01

    first co-author Jonathan O. Thurgood (QMUL) The simulation of three-wave interaction based plasma emission, an underlying mechanism for type III solar radio bursts, is a challenging task requiring fully-kinetic, multi-dimensional models. This paper aims to resolve a contradiction in past attempts, whereby some authors report that no such processes occur and others draw conflicting conclusions, by using 2D, fully kinetic, particle-in-cell simulations of relaxing electron beams. Here we present the results of particle-in-cell simulations which for different physical parameters permit or prohibit the plasma emission. We show that the possibility of plasma emission is contingent upon the frequency of the initial electrostatic waves generated by the bump-in-tail instability, and that these waves may be prohibited from participating in the necessary three-wave interactions due to the frequency beat requirements. We caution against simulating astrophysical radio bursts using unrealistically dense beams (a common approach which reduces run time), as the resulting non-Langmuir characteristics of the initial wave modes significantly suppresses the emission. Comparison of our results indicates that, contrary to the suggestions of previous authors, a plasma emission mechanism based on two counter-propagating beams is unnecessary in astrophysical context. Finally, we also consider the action of the Weibel instability, which generates an electromagnetic beam mode. As this provides a stronger contribution to electromagnetic energy than the emission, we stress that evidence of plasma emission in simulations must disentangle the two contributions and not simply interpret changes in total electromagnetic energy as the evidence of plasma emission. In summary, we present the first self-consistent demonstration of fundamental and harmonic plasma emission from a single-beam system via fully kinetic numerical simulation. Pre-print can be found at http://astro.qmul.ac.uk/~tsiklauri/jtdt1

  3. Comparison of particle mass and solid particle number (SPN) emissions from a heavy-duty diesel vehicle under on-road driving conditions and a standard testing cycle.

    PubMed

    Zheng, Zhongqing; Durbin, Thomas D; Xue, Jian; Johnson, Kent C; Li, Yang; Hu, Shaohua; Huai, Tao; Ayala, Alberto; Kittelson, David B; Jung, Heejung S

    2014-01-01

    It is important to understand the differences between emissions from standard laboratory testing cycles and those from actual on-road driving conditions, especially for solid particle number (SPN) emissions now being regulated in Europe. This study compared particle mass and SPN emissions from a heavy-duty diesel vehicle operating over the urban dynamometer driving schedule (UDDS) and actual on-road driving conditions. Particle mass emissions were calculated using the integrated particle size distribution (IPSD) method and called MIPSD. The MIPSD emissions for the UDDS and on-road tests were more than 6 times lower than the U.S. 2007 heavy-duty particulate matter (PM) mass standard. The MIPSD emissions for the UDDS fell between those for the on-road uphill and downhill driving. SPN and MIPSD measurements were dominated by nucleation particles for the UDDS and uphill driving and by accumulation mode particles for cruise and downhill driving. The SPN emissions were ∼ 3 times lower than the Euro 6 heavy-duty SPN limit for the UDDS and downhill driving and ∼ 4-5 times higher than the Euro 6 SPN limit for the more aggressive uphill driving; however, it is likely that most of the "solid" particles measured under these conditions were associated with a combination release of stored sulfates and enhanced sulfate formation associated with high exhaust temperatures, leading to growth of volatile particles into the solid particle counting range above 23 nm. Except for these conditions, a linear relationship was found between SPN and accumulation mode MIPSD. The coefficient of variation (COV) of SPN emissions of particles >23 nm ranged from 8 to 26% for the UDDS and on-road tests.

  4. 14 CFR 34.71 - Compliance with gaseous emission standards.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... TRANSPORTATION AIRCRAFT FUEL VENTING AND EXHAUST EMISSION REQUIREMENTS FOR TURBINE ENGINE POWERED AIRPLANES Test Procedures for Engine Exhaust Gaseous Emissions (Aircraft and Aircraft Gas Turbine Engines) §...

  5. 14 CFR 34.71 - Compliance with gaseous emission standards.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... TRANSPORTATION AIRCRAFT FUEL VENTING AND EXHAUST EMISSION REQUIREMENTS FOR TURBINE ENGINE POWERED AIRPLANES Test Procedures for Engine Exhaust Gaseous Emissions (Aircraft and Aircraft Gas Turbine Engines) §...

  6. Performance, emissions, and physical characteristics of a rotating combustion aircraft engine, supplement A

    NASA Technical Reports Server (NTRS)

    Lamping, R. K.; Manning, I.; Myers, D.; Tjoa, B.

    1980-01-01

    Testing was conducted using the basic RC2-75 engine, to which several modifications were incorporated which were designed to reduce the hydrocarbon emissions and reduce the specific fuel consumption. The modifications included close-in surface gap spark plugs, increased compression ratio rotors, and provisions for utilizing either side or peripheral intake ports, or a combination of the two if required. The proposed EPA emissions requirements were met using the normal peripheral porting. The specific fuel economy demonstrated for the modified RC2-75 was 283 g/kW-hr at 75% power and 101 brake mean effective pressure (BMEP) and 272.5 g/kW-hr at 75% power and 111 BMEP. The latter would result from rating the engine for takeoff at 285 hp and 5500 rpm, instead of 6000 rpm.

  7. Nitrogen oxide emissions and their control from uninstalled aircraft engines in enclosed test cells: Joint report to congress on the Environmental Protection Agency - Department of Transportation Study. Final report

    SciTech Connect

    1994-10-01

    The report was submitted to the Congress under mandate of Section 233 of the Clean Air Act Amendments of 1990. The report provides a characterization of aircraft engine test cells and their emissions. Various NOx control technologies that have been applied to combustion sources other than test cells are examined in the report for their applicability to test cells. Effects of NOx controls on the aircraft engine and aircraft engine test are also addressed. Finally, annual emissions from test cells are estimated and compared to total NOx emissions in the applicable ozone non-attainment areas.

  8. Exhaust particle and NOx emission performance of an SCR heavy duty truck operating in real-world conditions

    NASA Astrophysics Data System (ADS)

    Saari, Sampo; Karjalainen, Panu; Ntziachristos, Leonidas; Pirjola, Liisa; Matilainen, Pekka; Keskinen, Jorma; Rönkkö, Topi

    2016-02-01

    Particle and NOx emissions of an SCR equipped HDD truck were studied in real-world driving conditions using the "Sniffer" mobile laboratory. Real-time CO2 measurement enables emission factor calculation for NOx and particles. In this study, we compared three different emission factor calculation methods and characterised their suitability for real-world chasing experiments. The particle number emission was bimodal and dominated by the nucleation mode particles (diameter below 23 nm) having emission factor up to 1 × 1015 #/kgfuel whereas emission factor for soot (diameter above 23 nm that is consistent with the PMP standard) was typically 1 × 1014 #/kgfuel. The effect of thermodenuder on the exhaust particles indicated that the nucleation particles consisted mainly of volatile compounds, but sometimes there also existed a non-volatile core. The nucleation mode particles are not controlled by current regulations in Europe. However, these particles consistently form under atmospheric dilution in the plume of the truck and constitute a health risk for the human population that is exposed to those. Average NOx emission was 3.55 g/kWh during the test, whereas the Euro IV emission limit over transient testing is 3.5 g NOx/kWh. The on-road emission performance of the vehicle was very close to the expected levels, confirming the successful operation of the SCR system of the tested vehicle. Heavy driving conditions such as uphill driving increased both the NOx and particle number emission factors whereas the emission factor for soot particle number remains rather constant.

  9. Application of automobile emission control technology to light piston aircraft engines

    NASA Technical Reports Server (NTRS)

    Tripp, D.; Kittredge, G.

    1976-01-01

    The possibility was evaluated for achieving the EPA Standards for HC and CO emissions through the use of air-fuel ratio enleanment at selected power modes combined with improved air-fuel mixture preparation, and in some cases improved cooling. Air injection was also an effective approach for the reduction of HC and CO, particularly when combined with exhaust heat conservation techniques such as exhaust port liners.

  10. Controlling VOC and air toxic emissions from aircraft refinishing facilities -- A new approach

    SciTech Connect

    Ayer, J.

    1997-12-31

    Preliminary studies conducted by the EPA and Air Force indicate that significant cost reductions are achievable by reducing booth exhaust flow rates via recirculation. Based on these results, the EPA and the US Marine Corps launched a full scale demonstration program in which several paint booths were modified at the Barstow MCLB to encompass recirculation and other ventilation system optimization strategies. Additionally, the booth exhaust streams were vented to an innovative VOC emission control device that has extremely low operating costs. The paper describes this full-scale demonstration program in which booth exhaust flow rates were safely reduced from 143,000 cfm to 44,000 cfm. This program (completed in September, 1996) encompassed several innovative elements, including: Permanent installation of split-flow/recirculation ventilation in 3 high production paint booths. Use of Variable Frequency Drive Fans to continually reduce booth flow rates to the lowest level while maintaining compliance with OSHA mandates. Integration of an innovative monitoring system using Fourier Transform Infrared (FTIR) to continuously monitor/speciate organic compound concentrations in recirculation ducts and ensure safe system operation. Installation of an ambient temperature emission control system that oxidizes the exhaust stream VOCs and is capable of instantaneous startup/shutdown operations; this is ideal for the Barstow MCLB high production operation. The ventilation systems were tested extensively to ensure a safe and efficient working environment; these test results indicate that recirculation and other system modifications successfully reduced flow rates to achieve low cost emission control. Results of a detailed economic analysis are also presented which demonstrate that ventilation system modification costs are quickly recovered from the installation/operation of a smaller VOC emission control device.

  11. Aircraft Emissions: Potential Effects on Ozone and Climate - A Review and Progress Report

    DTIC Science & Technology

    1977-03-01

    soil by biological processes; it is also apparently produced during combustion , as in coal -fired power plants (Craig, 1976). Also, N2 0 production by...given in Table 2.18. In general, very low NOx emission indices (3 or less) are based on the assumed implementation of lean premix combustion techniques...Ultra-low NO values (0.3) have also been demonstrated,x using very lean flames or catalytic combustion techniques. TABLE 2.17. NASA AD HOC COMMITTEE

  12. Emissions of an AVCO Lycoming 0-320-DIAD air cooled light aircraft engine as a function of fuel-air ratio, timing, and air temperature and humidity

    NASA Technical Reports Server (NTRS)

    Meng, P. R.; Skorobatckyi, M.; Cosgrove, D. V.; Kempke, E. E., Jr.

    1976-01-01

    A carbureted aircraft engine was operated over a range of test conditions to establish the exhaust levels over the EPA seven-mode emissions cycle. Baseline (full rich production limit) exhaust emissions at an induction air temperature of 59 F and near zero relative humidity were 90 percent of the EPA standard for HC, 35 percent for NOx, and 161 percent for CO. Changes in ignition timing around the standard 25 deg BTDC from 30 deg BTDC to 20 deg BTDC had little effect on the exhaust emissions. Retarding the timing to 15 deg BTDC increased both the HC and CO emissions and decreased NOx emissions. HC and CO emissions decreased as the carburetor was leaned out, while NOx emissions increased. The EPA emission standards were marginally achieved at two leanout conditions. Variations in the quantity of cooling air flow over the engine had no effect on exhaust emissions. Temperature-humidity effects at the higher values of air temperature and relative humidity tested indicated that the HC and CO emissions increased significantly, while the NOx emissions decreased.

  13. How are particle production, nucleon emission and target fragment evaporation processes interrelated in hadron-nucleus collisions?

    NASA Technical Reports Server (NTRS)

    Strugalski, Z.

    1985-01-01

    Relations between particle production, nucleon emission, and fragment evaporation processes were searched for in hadron-nucleus collisions. It was stated that: (1) the nucleon emission and target fragment evaporation proceed independently of the particle production process; and (2) relation between multiplicities of the emitted protons and of the evaporated charged fragments is expressed by simple formula.

  14. Measurement of Black Carbon and Particle Number Emission Factors from Individual Heavy-Duty Trucks

    SciTech Connect

    Ban-Weiss, George A.; Lunden, Melissa M.; Kirchstetter, Thomas W.; Harley, Robert A.

    2009-02-02

    Emission factors for black carbon (BC) and particle number (PN) were measured from 226 individual heavy-duty (HD) diesel-fueled trucks driving through a 1 km-long California highway tunnel in August 2006. Emission factors were based on concurrent increases in BC, PN, and CO{sub 2}B concentrations (measured at 1 Hz) that corresponded to the passage of individual HD trucks. The distributions of BC and PN emission factors from individual HD trucks are skewed, meaning that a large fraction of pollution comes from a small fraction of the in-use vehicle fleet. The highest-emitting 10% of trucks were responsible for {approx} 40% of total BC and PN emissions from all HD trucks. BC emissions were log-normally distributed with a mean emission factor of 1.7 g kg {sup -1} and maximum values of {approx} 10 g kg{sup -1}. Corresponding values for PN emission factors were 4.7 x 10{sup 15} and 4 x 10{sup 16} kg{sup -1}. There was minimal overlap among high-emitters of these two pollutants: only 1 of the 226 HD trucks measured was found to be among the highest 10% for both BC and PN. Monte Carlo resampling of the distribution of BC emission factors observed in this study revealed that uncertainties (1{sigma}) in extrapolating from a random sample of n HD trucks to a population mean emission factor ranged from {+-} 43% for n = 10 to {+-} 8% for n = 300, illustrating the importance of sufficiently large vehicle sample sizes in emissions studies. Studies with low sample sizes are also more easily biased due to misrepresentation of high-emitters. As vehicles become cleaner on average in future years, skewness of the emissions distributions will increase, and thus sample sizes needed to extrapolate reliably from a subset of vehicles to the entire in-use vehicle fleet are expected to become more of a challenge.

  15. Particle-Bound PAH Emission from the Exhaust of Combustion Chamber

    NASA Astrophysics Data System (ADS)

    Asgari Lamjiri, M.; Medrano, Y. S.; Guillaume, D. W.; Khachikian, C. S.

    2013-12-01

    [a]pyrene in most of the samples. Better recirculation between air and fuel in higher swirl numbers results in better combustion. In higher swirl numbers, the temperature of the combustion process increases which leads to a more complete combustion. Another result of higher swirl number is a longer residence time which allows the organic substances in the fuel to remain in the reaction longer and also leads to a more complete combustion. The preliminary results from particle analyzer show that the abundance ratio of smaller particles to larger particles increases at higher swirl numbers. For example, at swirl 86, the abundance ratio of 0.3 micron particles to 0.7 micron particles was 400 while at swirl 0, this ratio was 35. Smaller particles have higher specific surface area which allows for more PAH adsorption. The preliminary results show that operating the jet engine at higher swirl numbers can have positive or negative effects on particle-bound PAH emissions. Higher temperature and residence time as well as better mixture of fuel and air can reduce PAH emission while generating more small size particles can increase surface available for PAH adsorption and, as a result, increases PAH emission. In future experiments, particle-bound PAHs of different swirl numbers will be compared in order to find a swirl number range which generates fewer Particle-bound PAHs.

  16. Diesel passenger car PM emissions: From Euro 1 to Euro 4 with particle filter

    NASA Astrophysics Data System (ADS)

    Tzamkiozis, Theodoros; Ntziachristos, Leonidas; Samaras, Zissis

    2010-03-01

    This paper examines the impact of the emission control and fuel technology development on the emissions of gaseous and, in particular, PM pollutants from diesel passenger cars. Three cars in five configurations in total were measured, and covered the range from Euro 1 to Euro 4 standards. The emission control ranged from no aftertreatment in the Euro 1 case, an oxidation catalyst in Euro 2, two oxidation catalysts and exhaust gas recirculation in Euro 3 and Euro 4, while a catalyzed diesel particle filter (DPF) fitted in the Euro 4 car led to a Euro 4 + DPF configuration. Both certification test and real-world driving cycles were employed. The results showed that CO and HC emissions were much lower than the emission standard over the hot-start real-world cycles. However, vehicle technologies from Euro 2 to Euro 4 exceeded the NOx and PM emission levels over at least one real-world cycle. The NOx emission level reached up to 3.6 times the certification level in case of the Euro 4 car. PM were up to 40% and 60% higher than certification level for the Euro 2 and Euro 3 cars, while the Euro 4 car emitted close or slightly below the certification level over the real-world driving cycles. PM mass reductions from Euro 1 to Euro 4 were associated with a relevant decrease in the total particle number, in particular over the certification test. This was not followed by a respective reduction in the solid particle number which remained rather constant between the four technologies at 0.86 × 10 14 km -1 (coefficient of variation 9%). As a result, the ratio of solid vs. total particle number ranged from ˜50% in Euro 1-100% in Euro 4. A significant reduction of more than three orders of magnitude in solid particle number is achieved with the introduction of the DPF. However, the potential for nucleation mode formation at high speed from the DPF car is an issue that needs to be considered in the over all assessment of its environmental benefit. Finally, comparison of the

  17. On-road measurement of particle emission in the exhaust plume of a diesel passenger car.

    PubMed

    Vogt, Rainer; Scheer, Volker; Casati, Roberto; Benter, Thorsten

    2003-09-15

    Particle size distributions were measured under real world dilution conditions in the exhaust plume of a diesel passenger car closely followed by a mobile laboratory on a high speed test track. Under carefully controlled conditions the exhaust plume was continuously sampled and analyzed inside the mobile laboratory. Exhaust particle size distribution data were recorded together with exhaust gas concentrations, i.e., CO, CO2, and NO(x), and compared to data obtained from the same vehicle tested on a chassis dynamometer. Good agreement was found for the soot mode particles which occurred at a geometric mean diameter of approximately 50 nm and a total particle emission rate of 10(14) particles km(-1). Using 350 ppm high sulfur fuel and the standard oxidation catalyst a bimodal size distribution with a nucleation mode at 10 nm was observed at car velocities of 100 km h(-1) and 120 km h(-1), respectively. Nucleation mode particles were only present if high sulfur fuel was used with the oxidation catalyst installed. This is in agreement with prior work that these particles are of semivolatile nature and originate from the nucleation of sulfates formed inside the catalyst. Temporal effects of the occurrence of nucleation mode particles during steady-state cruising and the dynamical behavior during acceleration and deceleration were investigated.

  18. Thermionic and photoelectric emission of electrons from positively charged particles in a plasma with Debye shielding

    NASA Astrophysics Data System (ADS)

    Sodha, Mahendra Singh; Mishra, Rashmi; Srivastava, Sweta; Mishra, Sanjay Kumar

    2015-09-01

    By utilizing the recent concept [G. Delzanno et al., Phys. Plasmas 12, 062102 (2005) and G. Delzanno and X. Tang, Phys. Rev. Lett. 113, 035002 (2014)] that the radial potential, experienced by an electron in the vicinity of a positively charged spherical particle depends on the transverse momentum of the electron, we have evaluated the rate of thermionic and photoelectron emission from a positively charged spherical particle and the corresponding average electron energy in a plasma, with Debye Screening. The effect of screening is manifested in the magnitude of a maximum in the radial potential energy versus r curve and is characterized by a parameter β which depends solely on ( r 0 / λ ) . Simple expressions for the change in the rates of emission and corresponding electron energy due to inclusion of the mechanism (mentioned above) in the analysis have been derived. The results of numerical computations have been presented and discussed. Simple expressions for the rates of electron emission from positively charged particles and corresponding average electron energy are necessary in the study of kinetics of complex plasmas. This work suffers from the limitation that the Debye length and even the nature of screening is not apriori known. In general, the evaluation of the nature of shielding and the shielding length requires a self consistent computation, similar to that carried out by Delzanno and Tang [Phys. Rev. Lett. 113, 035002 (2014)] in their work on thermionic emission in vacuum.

  19. Particle emissions from district heating units operating on three commonly used biofuels

    NASA Astrophysics Data System (ADS)

    Wierzbicka, A.; Lillieblad, L.; Pagels, J.; Strand, M.; Gudmundsson, A.; Gharibi, A.; Swietlicki, E.; Sanati, M.; Bohgard, M.

    The aim of this study was to characterise particle emissions from district heating units operating on three commonly used biofuels: forest residues, pellets and sawdust. Boilers used in the three district heating units were of moving grate type, with the maximum thermal output between 1 and 1.5 MW. The measurements were done after multicyclones, the only particle removal devices installed, therefore the direct emissions to ambient air were characterised. Number and mass size distributions were determined. Elemental composition of the particles was determined by particle induced X-ray emissions analysis (PIXE) and thermal-optical analysis. Particles' morphology was assessed on the basis of transmission electron microscopy (TEM). Total number concentration of emitted particles with aerodynamic diameter smaller than 5 μm (PM5) at medium operation load ranged from 6.3 to 7.7×10 7 particles/cm n3, with the slightly higher values from combustion of forest residues. PM5 mass concentration at medium load from low pressure impactor measurements ranged between 51 and 120 mg/m n3, with the highest values from unit operating on forest residues. Both PM5 mass and total number concentrations were dominated by fine mode contributions i.e. particles with aerodynamic diameter smaller than 1 μm (PM1). Elements determined by PIXE ( Z>12) contributed to 21-34% of PM1 mass, of which K, S, Cl and Ca contributed to 18-33% of PM1 mass, and Zn, Mn, Fe, Cr, Pb and Cd to 1-3%. Emitted concentrations of heavy metals depended on type of the fuel and operating load. Particulate organic (OC) and elemental (EC) carbon contribution to PM1 ranged from 1-19% and 0-56%, respectively. Particulate OC concentrations strongly depended on the operation load regardless the type of the fuel, while EC concentrations seemed to depend both on load and the type of the fuel. Considering the potential public health implications of the obtained results, further research is needed to carefully assess the impact

  20. Biomass burning emissions of trace gases and particles in marine air at Cape Grim, Tasmania

    NASA Astrophysics Data System (ADS)

    Lawson, S. J.; Keywood, M. D.; Galbally, I. E.; Gras, J. L.; Cainey, J. M.; Cope, M. E.; Krummel, P. B.; Fraser, P. J.; Steele, L. P.; Bentley, S. T.; Meyer, C. P.; Ristovski, Z.; Goldstein, A. H.

    2015-12-01

    Biomass burning (BB) plumes were measured at the Cape Grim Baseline Air Pollution Station during the 2006 Precursors to Particles campaign, when emissions from a fire on nearby Robbins Island impacted the station. Measurements made included non-methane organic compounds (NMOCs) (PTR-MS), particle number size distribution, condensation nuclei (CN) > 3 nm, black carbon (BC) concentration, cloud condensation nuclei (CCN) number, ozone (O3), methane (CH4), carbon monoxide (CO), hydrogen (H2), carbon dioxide (CO2), nitrous oxide (N2O), halocarbons and meteorology. During the first plume strike event (BB1), a 4 h enhancement of CO (max ~ 2100 ppb), BC (~ 1400 ng m-3) and particles > 3 nm (~ 13 000 cm-3) with dominant particle mode of 120 nm were observed overnight. A wind direction change lead to a dramatic reduction in BB tracers and a drop in the dominant particle mode to 50 nm. The dominant mode increased in size to 80 nm over 5 h in calm sunny conditions, accompanied by an increase in ozone. Due to an enhancement in BC but not CO during particle growth, the presence of BB emissions during this period could not be confirmed. The ability of particles > 80 nm (CN80) to act as CCN at 0.5 % supersaturation was investigated. The ΔCCN / ΔCN80 ratio was lowest during the fresh BB plume (56 ± 8 %), higher during the particle growth period (77 ± 4 %) and higher still (104 ± 3 %) in background marine air. Particle size distributions indicate that changes to particle chemical composition, rather than particle size, are driving these changes. Hourly average CCN during both BB events were between 2000 and 5000 CCN cm-3, which were enhanced above typical background levels by a factor of 6-34, highlighting the dramatic impact BB plumes can have on CCN number in clean marine regions. During the 29 h of the second plume strike event (BB2) CO, BC and a range of NMOCs including acetonitrile and hydrogen cyanide (HCN) were clearly enhanced and some enhancements in O3 were observed

  1. Preparation of tourmaline nano-particles through a hydrothermal process and its infrared emission properties.

    PubMed

    Xue, Gang; Han, Chao; Liang, Jinsheng; Wang, Saifei; Zhao, Chaoyue

    2014-05-01

    Tourmaline nano-particles were successfully prepared via a hydrothermal process using HCl as an additive. The reaction temperature (T) and the concentration of HCI (C(HCl)) had effects on the size and morphology of the tourmaline nano-particles. The optimum reaction condition was that: T = 180 degrees C and C(HCl) = 0.1 mol/l. The obtained nano-particles were spherical with the diameter of 48 nm. The far-infrared emissivity of the product was 0.923. The formation mechnism of the tourmaline nano-particles might come from the corrosion of grain boundary between the tourmaline crystals in acidic hydrothermal conditions and then the asymmetric contraction of the crystals.

  2. Modeling fundamental plasma transport and particle-induced emission in a simplified Test Cell

    NASA Astrophysics Data System (ADS)

    Giuliano, Paul Nicholas

    This work involves the modeling of fundamental plasma physics processes occurring within environments that are similar to that of the discharge and plume regions of electric propulsion devices such as Hall effect thrusters. The research is conducted as a collaborative effort with the Plasma & Space Propulsion Laboratory at the University of California, Los Angeles (UCLA), as part of the University of Michigan/AFRL Center for Excellence in Electric Propulsion (MACEEP). Transport physics, such as particle-particle collisions and particle-induced electron emission, are simulated within the UCLA experimental facility and its representative electric propulsion environment. Simulation methods employed include the direct simulation Monte Carlo (DSMC) and particle-in-cell (PIC) techniques for the kinetic simulation of charged, rarefied species on high-performance computing architectures. Momentum- (MEX) and charge-exchange (CEX) collision cross-section models for Xe and Xe+, both total and differential, are successfully validated at collision energies of ˜1.5 keV within the novel facility. Heavy-species collisional transport models are validated and the importance of scattering anisotropy in this collision-dominated environment is shown. The theory of particle-induced electron emission (PIE) is then investigated in the context of the relevant energies and environments of the UCLA facility and electric propulsion devices and diagnostics. Reduced, semi-empirical models for total yield and emitted electron energy distribution functions that are easily implemented in a DSMC-PIC code are developed for the simulation of secondary-electron emission due to low-energy ions and high-energy atoms, even in the case of incomplete target-material information. These models are important for the characterization of electric propulsion devices due to the problematic nature of low-temperature plasma diagnostic techniques in which the emission of electrons is physically indistinguishable

  3. Measurements of size-segregated emission particles by a sampling system based on the cascade impactor

    SciTech Connect

    Janja Tursic; Irena Grgic; Axel Berner; Jaroslav Skantar; Igor Cuhalev

    2008-02-01

    A special sampling system for measurements of size-segregated particles directly at the source of emission was designed and constructed. The central part of this system is a low-pressure cascade impactor with 10 collection stages for the size ranges between 15 nm and 16 {mu}m. Its capability and suitability was proven by sampling particles at the stack (100{sup o}C) of a coal-fired power station in Slovenia. These measurements showed very reasonable results in comparison with a commercial cascade impactor for PM10 and PM2.5 and with a plane device for total suspended particulate matter (TSP). The best agreement with the measurements made by a commercial impactor was found for concentrations of TSP above 10 mg m{sup -3}, i.e., the average PM2.5/PM10 ratios obtained by a commercial impactor and by our impactor were 0.78 and 0.80, respectively. Analysis of selected elements in size-segregated emission particles additionally confirmed the suitability of our system. The measurements showed that the mass size distributions were generally bimodal, with the most pronounced mass peak in the 1-2 {mu}m size range. The first results of elemental mass size distributions showed some distinctive differences in comparison to the most common ambient anthropogenic sources (i.e., traffic emissions). For example, trace elements, like Pb, Cd, As, and V, typically related to traffic emissions, are usually more abundant in particles less than 1 {mu}m in size, whereas in our specific case they were found at about 2 {mu}m. Thus, these mass size distributions can be used as a signature of this source. Simultaneous measurements of size-segregated particles at the source and in the surrounding environment can therefore significantly increase the sensitivity of the contribution of a specific source to the actual ambient concentrations. 25 refs., 3 figs., 2 tabs.

  4. The Effect of Altitude Conditions on the Particle Emissions of a J85-GE-5L Turbojet Engine

    NASA Technical Reports Server (NTRS)

    Rickey, June Elizabeth

    1995-01-01

    Particles from a J85-GE-5L turbojet engine were measured over a range of engine speeds at simulated altitude conditions ranging from near sea level to 45,000 ft and at flight Mach numbers of 0.5 and 0.8. Samples were collected from the engine by using a specially designed probe positioned several inches behind the exhaust nozzle. A differential mobility particle sizing system was used to determine particle size. Particle data measured at near sea-level conditions were compared with Navy Aircraft Environmental Support Office (AESO) particle data taken from a GE-J85-4A engine at a sea-level static condition. Particle data from the J85 engine were also compared with particle data from a J85 combustor at three different simulated altitudes.

  5. Emissions of Trace Gases and Particles from Savanna Fires in Southern Africa

    NASA Technical Reports Server (NTRS)

    Sinha, Parikhit; Hobbs, Peter V.; Yokelson, Robert J.; Bertschi, Isaac T.; Blake, Donald R.; Simpson, Isobel J.; Gao, Song; Kirchstetter, Thomas W.; Novakov, Tica

    2003-01-01

    Airborne measurements made on initial smoke from 10 savanna fires in southern Africa provide quantitative data on emissions of 50 gaseous and particulate species, including carbon dioxide, carbon monoxide, sulfur dioxide, nitrogen oxides, methane, ammonia, dimethyl sulfide, nonmethane organic compounds, halocarbons, gaseous organic acids, aerosol ionic components, carbonaceous aerosols, and condensation nuclei (CN). Measurements of several of the gaseous species by gas chromatography and Fourier transform infrared spectroscopy are compared. Emission ratios and emission factors are given for eight species that have not been reported previously for biomass burning of savanna in southern Africa (namely, dimethyl sulfide, methyl nitrate, five hydrocarbons, and particles with diameters from 0.1 to 3 microns). The emission factor that we measured for ammonia is lower by a factor of 4, and the emission factors for formaldehyde, hydrogen cyanide, and CN are greater by factors of about 3, 20, and 3 - 15, respectively, than previously reported values. The new emission factors are used to estimate annual emissions of these species from savanna fires in Africa and worldwide.

  6. Emission rates of particle number, mass and black carbon by the Los Angeles International Airport (LAX) and its impact on air quality in Los Angeles

    NASA Astrophysics Data System (ADS)

    Shirmohammadi, Farimah; Sowlat, Mohammad H.; Hasheminassab, Sina; Saffari, Arian; Ban-Weiss, George; Sioutas, Constantinos

    2017-02-01

    This study describes a series of air monitoring measurements of particle number (PN), black carbon (BC) and PM2.5 mass concentrations in the vicinity of the Los Angeles International Airport (LAX) (roughly 150 m downwind of the LAX's south runways) as well as on-road measurements of the aforementioned pollutants using a mobile platform on three major freeways (i.e., I-110, I-105, and I-405) during May-July 2016. All measurements were performed in the "impact zone" of LAX with the predominant westerly winds from coast to inland. The overall impact of aircraft emissions from the LAX airport and its facilities in comparison to vehicular emissions from freeways on air quality was evaluated on a local scale (i.e. areas in the vicinity of the airport). PN concentration was, on average, 4.1 ± 1.2 times greater at the LAX site than on the studied freeways. Particle number emission factors for takeoffs and landings were comparable, with average values of 8.69 ×1015 particles/kg fuel and 8.16 ×1015 particles/kg fuel, respectively, and indicated a nearly 4-fold statistically significant reduction in PN emission factors for takeoffs during the past decade. BC emission factors were 0.12 ± 0.02 and 0.11 ± 0.01 g/kg fuel during takeoffs and landings, respectively. Additionally, the mean PM2.5 emission factor values for takeoffs and landings were also comparable, with values of 0.38 ± 0.04 and 0.40 ± 0.05 g/kg fuel, respectively. Within the impact zone of the airport, an area of roughly 100 km2 downwind of the LAX, measurements indicated that the LAX daily contributions to PN, BC, and PM2.5 were approximately 11, 2.5, and 1.4 times greater than those from the three surrounding freeways. These results underscore the significance of the LAX airport as a major source of pollution within its zone of impact comparing to freeway emissions.

  7. A PEMS study of the emissions of gaseous pollutants and ultrafine particles from gasoline- and diesel-fueled vehicles

    NASA Astrophysics Data System (ADS)

    Huang, Cheng; Lou, Diming; Hu, Zhiyuan; Feng, Qian; Chen, Yiran; Chen, Changhong; Tan, Piqiang; Yao, Di

    2013-10-01

    On-road emission measurements of gasoline- and diesel-fueled vehicles were conducted by a portable emission measurement system (PEMS) in Shanghai, China. Horiba OBS 2200 and TSI EEPS 3090 were employed to detect gaseous and ultrafine particle emissions during the tests. The driving-based emission factors of gaseous pollutants and particle mass and number were obtained on various road types. The average NOx emission factors of the diesel bus, diesel car, and gasoline car were 8.86, 0.68, and 0.17 g km-1, all of which were in excess of their emission limits. The particle number emission factors were 7.06 × 1014, 6.08 × 1014, and 1.57 × 1014 km-1, generally higher than the results for similar vehicle types reported in the previous studies. The size distributions of the particles emitted from the diesel vehicles were mainly concentrated in the accumulation mode, while those emitted from the gasoline car were mainly distributed in the nucleation mode. Both gaseous and particle emission rates exhibit significant correlations with the change in vehicle speed and power demand. The lowest emission rates for each vehicle type were produced during idling. The highest emission rates for each vehicle type were generally found in high-VSP bins. The particle number emission rates of the gasoline car show the strongest growth trend with increasing VSP and speed. The particle number emission for the gasoline car increased by 3 orders of magnitude from idling to the highest VSP and driving speed conditions. High engine power caused by aggressive driving or heavy loads is the main contributor to high emissions for these vehicles in real-world situations.

  8. Temperature and burning history affect emissions of greenhouse gases and aerosol particles from tropical peatland fire

    NASA Astrophysics Data System (ADS)

    Kuwata, Mikinori; Kai, Fuu Ming; Yang, Liudongqing; Itoh, Masayuki; Gunawan, Haris; Harvey, Charles F.

    2017-01-01

    Tropical peatland burning in Asia has been intensifying over the last decades, emitting huge amounts of gas species and aerosol particles. Both laboratory and field studies have been conducted to investigate emission from peat burning, yet a significant variability in data still exists. We conducted a series of experiments to characterize the gas and particulate matter emitted during burning of a peat sample from Sumatra in Indonesia. Heating temperature of peat was found to regulate the ratio of CH4 to CO2 in emissions (ΔCH4/ΔCO2) as well as the chemical composition of particulate matter. The ΔCH4/ΔCO2 ratio was larger for higher temperatures, meaning that CH4 emission is more pronounced at these conditions. Mass spectrometric analysis of organic components indicated that aerosol particles emitted at higher temperatures had more unsaturated bonds and ring structures than that emitted from cooler fires. The result was consistently confirmed by nuclear magnetic resonance analysis. In addition, CH4 emitted by burning charcoal, which is derived from previously burned peat, was lower by at least an order of magnitude than that from fresh peat. These results highlight the importance of both fire history and heating temperature for the composition of tropical peat-fire emissions. They suggest that remote sensing technologies that map fire histories and temperatures could provide improved estimates of emissions.

  9. Aerosol-CFD modelling of ultrafine and black carbon particle emission, dilution, and growth near roadways

    NASA Astrophysics Data System (ADS)

    Huang, L.; Gong, S. L.; Gordon, M.; Liggio, J.; Staebler, R. M.; Stroud, C. A.; Lu, G.; Mihele, C.; Brook, J. R.; Jia, C. Q.

    2014-05-01

    Many studies have shown that on-road vehicle emissions are the dominant source of ultrafine particles (UFP; diameter < 100 nm) in urban areas and near-roadway environments. In order to advance our knowledge on the complex interactions and competition among atmospheric dilution, dispersion and dynamics of UFPs, an aerosol dynamics-CFD coupled model is developed and validated against field measurements. A unique approach of applying periodic boundary conditions is proposed to model pollutant dispersion and dynamics in one unified domain from the tailpipe level to the ambient near-road environment. This approach significantly reduces the size of the computational domain, and therefore, allows fast simulation of multiple scenarios. The model is validated against measured turbulent kinetic energy (TKE) and pollution gradients near a major highway. Through a model sensitivity analysis, the relative importance of individual aerosol dynamical processes on the total particle number concentration (N) and particle number-size distribution (PSD) near a highway is investigated. The results demonstrate that (1) coagulation has a negligible effect on N and particle growth, (2) binary homogeneous nucleation (BHN) of H2SO4-H2O is likely responsible for elevated N closest to the road, (3) N and particle growth are very sensitive to the condensation of semi-volatile organics (SVOCs), particle dry deposition, and the interaction between these processes. The results also indicate that, without the proper treatment of atmospheric boundary layer (i.e. its wind profile and turbulence quantities), the nucleation rate would be underestimated by a factor of 5 in the vehicle wake region due to overestimated mixing. Therefore, introducing ABL conditions to activity-based emission models may potentially improve their performance in estimating UFP traffic emissions.

  10. Characteristics of SME biodiesel-fueled diesel particle emissions and the kinetics of oxidation.

    PubMed

    Jung, Heejung; Kittelson, David B; Zachariah, Michael R

    2006-08-15

    Biodiesel is one of the most promising alternative diesel fuels. As diesel emission regulations have become more stringent, the diesel particulate filter (DPF) has become an essential part of the aftertreatment system. Knowledge of kinetics of exhaust particle oxidation for alternative diesel fuels is useful in estimating the change in regeneration behavior of a DPF with such fuels. This study examines the characteristics of diesel particulate emissions as well as kinetics of particle oxidation using a 1996 John Deere T04045TF250 off-highway engine and 100% soy methyl ester (SME) biodiesel (B100) as fuel. Compared to standard D2 fuel, this B100 reduced particle size, number, and volume in the accumulation mode where most of the particle mass is found. At 75% load, number decreased by 38%, DGN decreased from 80 to 62 nm, and volume decreased by 82%. Part of this decrease is likely associated with the fact that the particles were more easily oxidized. Arrhenius parameters for the biodiesel fuel showed a 2-3times greater frequency factor and approximately 6 times higher oxidation rate compared to regular diesel fuel in the range of 700-825 degrees C. The faster oxidation kinetics should facilitate regeneration when used with a DPF.

  11. Agricultural fires in the southeastern U.S. during SEAC4RS: Emissions of trace gases and particles and evolution of ozone, reactive nitrogen, and organic aerosol

    NASA Astrophysics Data System (ADS)

    Liu, Xiaoxi; Zhang, Y.; Huey, L. G.; Yokelson, R. J.; Wang, Y.; Jimenez, J. L.; Campuzano-Jost, P.; Beyersdorf, A. J.; Blake, D. R.; Choi, Y.; St. Clair, J. M.; Crounse, J. D.; Day, D. A.; Diskin, G. S.; Fried, A.; Hall, S. R.; Hanisco, T. F.; King, L. E.; Meinardi, S.; Mikoviny, T.; Palm, B. B.; Peischl, J.; Perring, A. E.; Pollack, I. B.; Ryerson, T. B.; Sachse, G.; Schwarz, J. P.; Simpson, I. J.; Tanner, D. J.; Thornhill, K. L.; Ullmann, K.; Weber, R. J.; Wennberg, P. O.; Wisthaler, A.; Wolfe, G. M.; Ziemba, L. D.

    2016-06-01

    Emissions from 15 agricultural fires in the southeastern U.S. were measured from the NASA DC-8 research aircraft during the summer 2013 Studies of Emissions and Atmospheric Composition, Clouds and Climate Coupling by Regional Surveys (SEAC4RS) campaign. This study reports a detailed set of emission factors (EFs) for 25 trace gases and 6 fine particle species. The chemical evolution of the primary emissions in seven plumes was examined in detail for ~1.2 h. A Lagrangian plume cross-section model was used to simulate the evolution of ozone (O3), reactive nitrogen species, and organic aerosol (OA). Observed EFs are generally consistent with previous measurements of crop residue burning, but the fires studied here emitted high amounts of SO2 and fine particles, especially primary OA and chloride. Filter-based measurements of aerosol light absorption implied that brown carbon (BrC) was ubiquitous in the plumes. In aged plumes, rapid production of O3, peroxyacetyl nitrate (PAN), and nitrate was observed with ΔO3/ΔCO, ΔPAN/ΔNOy, and Δnitrate/ΔNOy reaching ~0.1, ~0.3, and ~0.3. For five selected cases, the model reasonably simulated O3 formation but underestimated PAN formation. No significant evolution of OA mass or BrC absorption was observed. However, a consistent increase in oxygen-to-carbon (O/C) ratios of OA indicated that OA oxidation in the agricultural fire plumes was much faster than in urban and forest fire plumes. Finally, total annual SO2, NOx, and CO emissions from agricultural fires in Arkansas, Louisiana, Mississippi, and Missouri were estimated (within a factor of ~2) to be equivalent to ~2% SO2 from coal combustion and ~1% NOx and ~9% CO from mobile sources.

  12. Spontaneous emission of a chiral molecule near a cluster of two chiral spherical particles

    SciTech Connect

    Guzatov, D V; Klimov, V V

    2015-03-31

    We have obtained and investigated analytical expressions for the radiative spontaneous decay rate of a chiral (optically active) molecule located near a cluster of two identical chiral (biisotropic) spherical particles. It is found that the composition of the particles, their location and size have a significant effect on the spontaneous emission of chiral molecules. In particular, it is shown that in the case of nanoparticles of chiral metamaterials, the radiative spontaneous decay rate for the 'right-' and 'left-handed' enantiomers of chiral molecules located in the gap of the cluster are significantly different. (metamaterials)

  13. Flux Calculation Using CARIBIC DOAS Aircraft Measurements: SO2 Emission of Norilsk

    NASA Technical Reports Server (NTRS)

    Walter, D.; Heue, K.-P.; Rauthe-Schoech, A.; Brenninkmeijer, C. A. M.; Lamsal, L. N.; Krotkov, N. A.; Platt, U.

    2012-01-01

    Based on a case-study of the nickel smelter in Norilsk (Siberia), the retrieval of trace gas fluxes using airborne remote sensing is discussed. A DOAS system onboard an Airbus 340 detected large amounts of SO2 and NO2 near Norilsk during a regular passenger flight within the CARIBIC project. The remote sensing data were combined with ECMWF wind data to estimate the SO2 output of the Norilsk industrial complex to be around 1 Mt per year, which is in agreement with independent estimates. This value is compared to results using data from satellite remote sensing (GOME, OMI). The validity of the assumptions underlying our estimate is discussed, including the adaptation of this method to other gases and sources like the NO2 emissions of large industries or cities.

  14. Impacts of natural emission sources on particle pollution levels in Europe

    NASA Astrophysics Data System (ADS)

    Liora, Natalia; Poupkou, Anastasia; Giannaros, Theodore M.; Kakosimos, Konstantinos E.; Stein, Olaf; Melas, Dimitrios

    2016-07-01

    The main objective of this work is the study of the impact of windblown dust, sea-salt aerosol and biogenic emissions on particle pollution levels in Europe. The Natural Emissions MOdel (NEMO) and the modelling system consisted of the Weather Research and Forecasting model (WRF) and the Comprehensive Air Quality model with extensions (CAMx) were applied in a 30 km horizontal resolution grid, which covered Europe and the adjacent areas for the year 2009. Air quality simulations were performed for different emission scenarios in order to study the contribution of each natural emission source individually and together to air quality levels in Europe. The simulations reveal that the exclusion of windblown dust emissions decreases the mean seasonal PM10 levels by more than 3.3 μg/m3 (∼20%) in the Eastern Mediterranean during winter while an impact of 3 μg/m3 was also found during summer. The results suggest that sea-salt aerosol has a significant effect on PM levels and composition. Eliminating sea-salt emissions reduces PM10 seasonal concentrations by around 10 μg/m3 in Mediterranean Sea during summer while a decrease of up to 6 μg/m3 is found in Atlantic Ocean during autumn. Sea-salt particles also interact with the anthropogenic component and therefore their absence in the atmosphere decreases significantly the nitrates in aerosols where shipping activities are present. The exclusion of biogenic emissions in the model runs leads to a significant reduction of secondary organic aerosols of more than 90% while an increase in PM2.5 levels in central Europe and Eastern Mediterranean is found due to their interaction with anthropogenic component.

  15. Proposed Rule and Related Materials for Proposed Finding That Greenhouse Gas Emissions From Aircraft Cause or Contribute to Air Pollution That May Reasonably Be Anticipated To Endanger Public Health and Welfare and Advance Notice of Proposed Rulemaking

    EPA Pesticide Factsheets

    Proposed Rule and Related Materials for Proposed Finding That Greenhouse Gas Emissions From Aircraft Cause or Contribute to Air Pollution That May Reasonably Be Anticipated To Endanger Public Health and Welfare and Advance Notice of Proposed Rulemaking

  16. Determination of single particle mass spectral signatures from light-duty vehicle emissions.

    PubMed

    Sodeman, David A; Toner, Stephen M; Prather, Kimberly A

    2005-06-15

    observed in the chemical composition of particles emitted within the different car categories as well as for the same car operating under different driving conditions. Two-minute temporal resolution measurements provide information on the chemical classes as they evolved during the FTP cycle. The first two minutes of the cold start produced more than 5 times the number of particles than any other portion of the cycle, with one class of ultrafine particles (EC coupled with Ca, OC, and phosphate) preferentially produced. By number, the three EC with Ca classes (which also contained OC, phosphate, and sulfate) were the most abundant classes produced by the nonsmoking vehicles. The smoker category produced the highest number of particles, with the dominant classes being OC comprised of substituted monoaromatic compounds and PAHs, coupled with Ca and phosphate, thus suggesting used lubricating oil was associated with many of these particles. These studies show, by number, EC particles dominate gasoline emissions in the ultrafine size range particularlyforthe lowest emitting newer vehicles, suggesting the EC signature alone cannot be used as a unique tracer for diesels. This represents the first report of high time- and size-resolved chemical composition data showing the mixing state of nonrefractory elements in particles such as EC for vehicle emissions during dynamometer source testing.

  17. Effects of Gasoline Direct Injection Engine Operating Parameters on Particle Number Emissions

    SciTech Connect

    He, X.; Ratcliff, M. A.; Zigler, B. T.

    2012-04-19

    A single-cylinder, wall-guided, spark ignition direct injection engine was used to study the impact of engine operating parameters on engine-out particle number (PN) emissions. Experiments were conducted with certification gasoline and a splash blend of 20% fuel grade ethanol in gasoline (E20), at four steady-state engine operating conditions. Independent engine control parameter sweeps were conducted including start of injection, injection pressure, spark timing, exhaust cam phasing, intake cam phasing, and air-fuel ratio. The results show that fuel injection timing is the dominant factor impacting PN emissions from this wall-guided gasoline direct injection engine. The major factor causing high PN emissions is fuel liquid impingement on the piston bowl. By avoiding fuel impingement, more than an order of magnitude reduction in PN emission was observed. Increasing fuel injection pressure reduces PN emissions because of smaller fuel droplet size and faster fuel-air mixing. PN emissions are insensitive to cam phasing and spark timing, especially at high engine load. Cold engine conditions produce higher PN emissions than hot engine conditions due to slower fuel vaporization and thus less fuel-air homogeneity during the combustion process. E20 produces lower PN emissions at low and medium loads if fuel liquid impingement on piston bowl is avoided. At high load or if there is fuel liquid impingement on piston bowl and/or cylinder wall, E20 tends to produce higher PN emissions. This is probably a function of the higher heat of vaporization of ethanol, which slows the vaporization of other fuel components from surfaces and may create local fuel-rich combustion or even pool-fires.

  18. Effects of particle size on far infrared emission properties of tourmaline superfine powders.

    PubMed

    Meng, Junping; Jin, Wei; Liang, Jinsheng; Ding, Yan; Gan, Kun; Yuan, Youde

    2010-03-01

    Tourmaline superfine powders with different particle sizes were prepared by grinding, superfine ball milling, and high-speed centrifugation. The powders were characterized by scanning electron microscopy, X-ray diffraction, dynamic contact angle meter and tensiometry, and Fourier transform infrared spectrometry. The results show that tourmaline powders exhibit improved far infrared emission properties as the particle size decreases. The increased surface free energy and proportion of the polar component are considered to play an important role for their properties. The spontaneous polarization is increased, and the dipole moment of tourmaline is stimulated to a high energy level more easily for the chemical bond vibration, so that the energy is apt to emit by transition. In the range of 2000-500 cm(-1), the emissivity values of the samples with D50 size of 2.67 microm and 0.2 microm are 0.973 and 0.991, respectively.

  19. Introduction to the SONEX (Subsonic Assessment Ozone and Nitrogen Oxides Experiment) and POLINAT-2 (Pollution from Aircraft Emissions in the North Atlantic Flight Corridor) Special Issue

    NASA Technical Reports Server (NTRS)

    Thompson, Anne M.; Singh, Hanwant B.; Schlager, Hans; Einaudi, Franco (Technical Monitor)

    2000-01-01

    Emissions of atmospheric species from the engines of subsonic aircraft at cruise altitude (roughly, above seven kilometers) are of concern to scientists, the aviation industry and policymakers for two reasons. First, water vapor, soot and sulfur oxides, and related heterogeneous processes, may modify clouds and aerosols enough to perturb radiative forcing in the UT/LS (upper troposphere/lower stratosphere). A discussion of these phenomena appears in Chapter 3 of the IPCC Aviation Assessment (1999). An airborne campaign conducted to evaluate aviation effects on contrail, cirrus and cloud formation, is described in Geophysical Research Letters. The second concern arises from subsonic aircraft emissions of nitrogen oxides (NO + NO2 = NO(sub x)), CO, and hydrocarbons. These species may add to the background mixture of photochemically reactive species that form ozone. In the UT/LS, ozone is a highly effective greenhouse gas. The impacts of subsonic aircraft emissions on tropospheric NO(sub x) and ozone budgets have been studied with models that focus on UT chemistry [e.g. see discussions of individual models in Brasseur et al., 1998; Friedl et al., 1997; IPCC, 1999]. Depending on the model used, projected increases in the global subsonic aircraft fleet from 1992 to 2015 will lead to a 50-100 pptv increase in UT/LS NO. at 12 km (compared to 50-150 pptv background) in northern hemisphere midlatitudes. The corresponding 12-km ozone increase is 7-11 ppbv, or 5-10% (Chapter 4 in IPCC, 1999). Two major sources of uncertainties in model estimates of aviation effects are: (1) the often limited degree to which global models - the scale required to evaluate aircraft emissions - realistically simulate atmospheric transport and other physical processes; (2) limited UT/LS observations of trace gases with which to evaluate model performance. In response to the latter deficiency, a number of airborne campaigns aimed at elucidating the effect of aircraft on atmospheric nitrogen oxides

  20. Evidence for MeV Particle Emission from Ti Charged with Low Energy Deuterium Ions

    DTIC Science & Technology

    1991-12-18

    Low Energy Deuterium Ions GEORGE P. CHAMBERS, GRAHAM K. HUBLER AND KENNETH S. GRABOWSKI Surface Modification Branch Condensed Matter and Radiation...FUNDING NUMBERS Evidence for MeV Particle Emission From Ti Charged with Low Energy Deuterium Ions 46-3765-01 6. AUT1HOR(S) OR628 George P. Chambers... deuterium ions at high current density (0.2-0.4 mA.cm ) to investigate the reported occurrence of nuclear reations at ambient temperatures in deuteriumn

  1. Reducing ultrafine particle emissions using air injection in wood-burning cookstoves

    SciTech Connect

    Rapp, Vi H.; Caubel, Julien J.; Wilson, Daniel L.; Gadgil, Ashok J.

    2016-06-27

    In order to address the health risks and climate impacts associated with pollution from cooking on biomass fires, researchers have focused on designing new cookstoves that improve cooking performance and reduce harmful emissions, specifically particulate matter (PM). One method for improving cooking performance and reducing emissions is using air injection to increase turbulence of unburned gases in the combustion zone. Although air injection reduces total PM mass emissions, the effect on PM size-distribution and number concentration has not been thoroughly investigated. Using two new wood-burning cookstove designs from Lawrence Berkeley National Laboratory, this research explores the effect of air injection on cooking performance, PM and gaseous emissions, and PM size distribution and number concentration. Both cookstoves were created using the Berkeley-Darfur Stove as the base platform to isolate the effects of air injection. The thermal performance, gaseous emissions, PM mass emissions, and particle concentrations (ranging from 5 nm to 10 μm in diameter) of the cookstoves were measured during multiple high-power cooking tests. Finally, the results indicate that air injection improves cookstove performance and reduces total PM mass but increases total ultrafine (less than 100 nm in diameter) PM concentration over the course of high-power cooking.

  2. Reducing ultrafine particle emissions using air injection in wood-burning cookstoves

    DOE PAGES

    Rapp, Vi H.; Caubel, Julien J.; Wilson, Daniel L.; ...

    2016-06-27

    In order to address the health risks and climate impacts associated with pollution from cooking on biomass fires, researchers have focused on designing new cookstoves that improve cooking performance and reduce harmful emissions, specifically particulate matter (PM). One method for improving cooking performance and reducing emissions is using air injection to increase turbulence of unburned gases in the combustion zone. Although air injection reduces total PM mass emissions, the effect on PM size-distribution and number concentration has not been thoroughly investigated. Using two new wood-burning cookstove designs from Lawrence Berkeley National Laboratory, this research explores the effect of air injectionmore » on cooking performance, PM and gaseous emissions, and PM size distribution and number concentration. Both cookstoves were created using the Berkeley-Darfur Stove as the base platform to isolate the effects of air injection. The thermal performance, gaseous emissions, PM mass emissions, and particle concentrations (ranging from 5 nm to 10 μm in diameter) of the cookstoves were measured during multiple high-power cooking tests. Finally, the results indicate that air injection improves cookstove performance and reduces total PM mass but increases total ultrafine (less than 100 nm in diameter) PM concentration over the course of high-power cooking.« less

  3. On the emission of amines from terrestrial vegetation in the context of atmospheric new particle formation

    NASA Astrophysics Data System (ADS)

    Neftel, Albrecht; Sintermann, Jörg

    2015-04-01

    Airborne amines, specifically methylamines (MAs), play a key role in atmospheric new particle formation (NPF) by stabilising small molecule clusters. Agricultural emissions are assumed to constitute the most important MA source, but given the short atmospheric residence time of MAs, they can hardly have a direct impact on NFP events observed in remote regions. High MA contents as well as emissions by plants have already been described in the 19th century. Strong MA emissions predominantly occur during flowering as part of a pollination strategy. The behaviour is species specific, but examples of such species are common and widespread. In addition, vegetative plant tissue exhibiting high amounts of MAs might potentially lead to significant emissions, and the decomposition of organic material could constitute another source for airborne MAs. These mechanisms would provide sources, which could be crucial for the amine's role in NPF, especially in remote regions. Knowledge about vegetation-related amine emissions is, however, very limited and thus it is also an open question how Global Change and the intensified cycling of reactive nitrogen over the last 200 years have altered amine emissions from vegetation with a corresponding effect on NPF.

  4. Characterization of gas and particle emissions from laboratory burns of peat

    NASA Astrophysics Data System (ADS)

    Black, Robert R.; Aurell, Johanna; Holder, Amara; George, Ingrid J.; Gullett, Brian K.; Hays, Michael D.; Geron, Chris D.; Tabor, Dennis

    2016-05-01

    Peat cores collected from two locations in eastern North Carolina (NC, USA) were burned in a laboratory facility to characterize emissions during simulated field combustion. Particle and gas samples were analyzed to quantify emission factors for particulate matter (PM2.5), organic carbon (OC), elemental carbon, light absorbing carbon, absorption Angstrom exponent, metals, polycyclic aromatic hydrocarbons (PAHs), and polychlorinated dibenzodioxins/dibenzofurans (PCDDs/PCDFs). CO from the smoldering burns, up to 7 h in duration, contributed approximately 16% of the total carbon emitted. Emission factors for black carbon (BC) and light absorbing carbon (UVPM) were considerably lower than those found for forest litter burns. Emission factors for PCDDs/PCDFs were near published values for forest fuels, at 1-4 ng toxic equivalents (TEQ)/kg carbon burned (Cb). Total PAH concentrations of ≥12 mg/kg were higher than published data from biomass burns, but roughly the same in terms of toxicity. Application of these emission factors to the noteworthy 2008 "Evans Road" fire in NC indicates that PM2.5 and PCDD/PCDF emissions from this fire may have been 4-6% of the annual US inventory and 5% of the annual OC amount.

  5. Characterization of decay and emission rates of ultrafine particles in indoor ice rink.

    PubMed

    Kim, J; Lee, K

    2013-08-01

    The purposes of this study were to determine indoor ultrafine particle (UFP, diameter <100 nm) levels in ice rinks and to characterize UFP decay and emission rates. All 15 public ice rinks in Seoul were investigated for UFP and carbon monoxide (CO) concentrations. Three ice rinks did not show peaks in UFP concentrations, and one ice rink used two resurfacers simultaneously. High peaks of UFP and CO concentrations were observed when the resurfacer was operated. The average air change rate in the 11 ice rinks was 0.21 ± 0.13/h. The average decay rates of UFP number concentrations measured by the P-Trak and DiSCmini were 0.54 ± 0.21/h and 0.85 ± 0.34/h, respectively. The average decay rate of UFP surface area concentration was 0.33 ± 0.15/h. The average emission rates of UFP number concentrations measured by P-Trak and DiSCmini were 1.2 × 10(14) ± 6.5 × 10(13) particles/min and 3.3 × 10(14) ± 2.4 × 10(14) particles/min, respectively. The average emission rate of UFP surface area concentration was 3.1 × 10(11) ± 2.0 × 10(11) μm(2)/min. UFP emission rate was associated with resurfacer age. DiSCmini measured higher decay and emission rates than P-Trak due to their different measuring mechanisms and size ranges.

  6. Indoor emission, dispersion and exposure of total particle-bound polycyclic aromatic hydrocarbons during cooking

    NASA Astrophysics Data System (ADS)

    Gao, Jun; Jian, Yating; Cao, Changsheng; Chen, Lei; Zhang, Xu

    2015-11-01

    Cooking processes highly contribute to indoor polycyclic aromatic hydrocarbon (PAH) pollution. High molecular weight and potentially carcinogenic PAHs are generally found attached to small particles, i.e., particulate phase PAHs (PPAHs). Due to the fact that indoor particle dynamics have been clear, describing the indoor dynamics of cooking-generated PPAHs within a specific time span is possible. This paper attempted to quantify the dynamic emission rate, simultaneous spatial dispersion and individual exposure of PPAHs using a cooking source. Experiments were conducted in a real-scale kitchen chamber to elucidate the time-resolved emission and effect of edible oil temperature and mass. Numerical simulations based on indoor particle dynamics were performed to obtain the spatial dispersion and individual inhalation intake of PPAHs under different emission and ventilation conditions. The present work examined the preheating cooking stage, at which edible oil is heated up to beyond its smoke point. The dynamic emission rate peak point occurred much earlier than the oil heating temperature. The total PPAH emission ranged from 2258 to 6578 ng upon heating 40-85 g of edible oil. The overall intake fraction by an individual within a period of 10 min, including 3 min for heating and 7 min for natural cooling, was generally ∼1/10,000. An important outcome of this work was that the overall intake fraction could be represented by multiplying the range hood escape efficiency by the inhalation-to-ventilation rate ratio, which would be no greater than the same ratio. The methodology and results of this work were extendible for the number-based assessment of PPAHs. This work is expected to help us understand the health risks due to inhalation exposure to cooking-generated PPAHs in the kitchen.

  7. Advanced Low-Emissions Catalytic-Combustor Program, phase 1. [aircraft gas turbine engines

    NASA Technical Reports Server (NTRS)

    Sturgess, G. J.

    1981-01-01

    Six catalytic combustor concepts were defined, analyzed, and evaluated. Major design considerations included low emissions, performance, safety, durability, installations, operations and development. On the basis of these considerations the two most promising concepts were selected. Refined analysis and preliminary design work was conducted on these two concepts. The selected concepts were required to fit within the combustor chamber dimensions of the reference engine. This is achieved by using a dump diffuser discharging into a plenum chamber between the compressor discharge and the turbine inlet, with the combustors overlaying the prediffuser and the rear of the compressor. To enhance maintainability, the outer combustor case for each concept is designed to translate forward for accessibility to the catalytic reactor, liners and high pressure turbine area. The catalytic reactor is self-contained with air-cooled canning on a resilient mounting. Both selected concepts employed integrated engine-starting approaches to raise the catalytic reactor up to operating conditions. Advanced liner schemes are used to minimize required cooling air. The two selected concepts respectively employ fuel-rich initial thermal reaction followed by rapid quench and subsequent fuel-lean catalytic reaction of carbon monoxide, and, fuel-lean thermal reaction of some fuel in a continuously operating pilot combustor with fuel-lean catalytic reaction of remaining fuel in a radially-staged main combustor.

  8. Relating urban airborne particle concentrations to shipping using carbon based elemental emission ratios

    NASA Astrophysics Data System (ADS)

    Johnson, Graham R.; Juwono, Alamsyah M.; Friend, Adrian J.; Cheung, Hing-Cho; Stelcer, Eduard; Cohen, David; Ayoko, Godwin A.; Morawska, Lidia

    2014-10-01

    This study demonstrates a novel method for testing the hypothesis that variations in primary and secondary particle number concentration (PNC) in urban air are related to residual fuel oil combustion at a coastal port lying 30 km upwind, by examining the correlation between PNC and airborne particle composition signatures chosen for their sensitivity to the elemental contaminants present in residual fuel oil. Residual fuel oil combustion indicators were chosen by comparing the sensitivity of a range of concentration ratios to airborne emissions originating from the port. The most responsive were combinations of vanadium and sulphur concentration ([S], [V]) expressed as ratios with respect to black carbon concentration ([BC]). These correlated significantly with ship activity at the port and with the fraction of time during which the wind blew from the port. The average [V] when the wind was predominantly from the port was 0.52 ng m-3 (87%) higher than the average for all wind directions and 0.83 ng m-3 (280%) higher than that for the lowest vanadium yielding wind direction considered to approximate the natural background. Shipping was found to be the main source of V impacting urban air quality in Brisbane. However, contrary to the stated hypothesis, increases in PNC related measures did not correlate with ship emission indicators or ship traffic. Hence at this site ship emissions were not found to be a major contributor to PNC compared to other fossil fuel combustion sources such as road traffic, airport and refinery emissions.

  9. Effects of Aftermarket Control Technologies on Gas and Particle Phase Oxidative Potential from Diesel Engine Emissions.

    PubMed

    Pavlovic, Jelica; Holder, Amara L; Yelverton, Tiffany L B

    2015-09-01

    Particulate matter (PM) originating from diesel combustion is a public health concern due to its association with adverse effects on respiratory and cardiovascular diseases and lung cancer. This study investigated emissions from three stationary diesel engines (gensets) and varying power output (230 kW, 400 kW, and 600 kW) at 50% and 90% load to determine concentrations of gaseous (GROS) and PM reactive oxygen species (PMROS). In addition, the influence of three modern emission control technologies on ROS emissions was evaluated: active and passive diesel particulate filters (A-DPF and P-DPF) and a diesel oxidation catalyst (DOC). PMROS made up 30-50% of the total ROS measured without aftermarket controls. All applied controls removed PMROS by more than 75% on average. However, the oxidative potential of PM downstream of these devices was not diminished at the same rate and particles surviving the A-PDF had an even higher oxidative potential on a per PM mass basis compared to the particles emitted by uncontrolled gensets. Further, the GROS as compared to PMROS emissions were not reduced with the same efficiency (<36%). GROS concentrations were highest with the DOC in use, indicating continued formation of GROS with this control. Correlation analyses showed that PMROS and to a lesser extent GROS have a good correlation with semivolatile organic carbon (OC1) subfraction. In addition, results suggest that chemical composition, rather than PM size, is responsible for differences in the PM oxidative potential.

  10. Transmission and Emission of Solar Energetic Particles in Semi-transparent Shocks

    NASA Astrophysics Data System (ADS)

    Kocharov, Leon; Laitinen, Timo; Usoskin, Ilya; Vainio, Rami

    2014-06-01

    While major solar energetic particle (SEP) events are associated with coronal mass ejection (CME)-driven shocks in solar wind, accurate SEP measurements reveal that more than one component of energetic ions exist in the beginning of the events. Solar electromagnetic emissions, including nuclear gamma-rays, suggest that high-energy ions could also be accelerated by coronal shocks, and some of those particles could contribute to SEPs in interplanetary space. However, the CME-driven shock in solar wind is thought to shield any particle source beneath the shock because of the strong scattering required for the diffusive shock acceleration. In this Letter, we consider a shock model that allows energetic particles from the possible behind-shock source to appear in front of the shock simultaneously with SEPs accelerated by the shock itself. We model the energetic particle transport in directions parallel and perpendicular to the magnetic field in a spherical shock expanding through the highly turbulent magnetic sector with an embedded quiet magnetic tube, which makes the shock semi-transparent for energetic particles. The model energy spectra and time profiles of energetic ions escaping far upstream of the shock are similar to the profiles observed during the first hour of some gradual SEP events.

  11. Measurements of Gas and Particle Phase Emissions From Munitions Detonation in a Field Environment

    NASA Astrophysics Data System (ADS)

    Fortner, E. C.; Knighton, W. B.; Timko, M.; Wood, E.; Onasch, T. B.; Kolb, C. E.; Beardsley, H. M.

    2007-12-01

    During the Point of Fire (POF) field campaign conducted at Fort Sill Oklahoma U.S.A. in March 2007 a suite of real- time trace gas and fine (submicron) particulate matter (PM) instrumentation characterized the point of fire emission plumes from large, medium and small caliber weapons systems. Muzzle emission plumes were measured and where appropriate, breach plumes and gun crew breathing zone measurements were also conducted. Aerosol measurements were conducted with an aerosol mass spectrometer (Aerodyne CTOF-AMS) for particle composition, condensation particle counter (CPC) for particle number density and DUSTRAK aerosol monitor for particle mass. Gas phase measurements included CO, CO2, NOx and a variety of trace gas species measured by proton transfer reaction mass spectrometry (PTR-MS) including hydrogen cyanide (HCN), acetonitrile, acrylonitrile, benzene, toluene, benzonitrile and styrene. In the majority of the plume measurements, HCN was the most prominent compound measured by PTR-MS. Quantification of HCN by PTR-MS is difficult due to its proton affinity being close enough to that of water to allow a significant backward reaction of protonated HCN with water, reducing the detection sensitivity and making the response dependent on humidity. We have developed a quantification procedure for HCN based on laboratory measurements of a calibration gas standard of HCN, which allows the humidity dependence to be extracted directly from the proton hydrate ion intensities. The correction factors for HCN are quite significant varying between 10 and 30 depending on sample humidity.

  12. Emission factors and detailed chemical composition of smoke particles from the 2010 wildfire season

    NASA Astrophysics Data System (ADS)

    Vicente, Ana; Alves, Célia; Calvo, Ana I.; Fernandes, Ana P.; Nunes, Teresa; Monteiro, Cristina; Almeida, Susana Marta; Pio, Casimiro

    2013-06-01

    This paper complements the information previously published (Atmospheric Environment 45, 641-649) on gaseous and particulate emissions from wildfires in Portugal for summer 2009, in an attempt at obtaining more extensive, complete and representative databases on emission factors and detailed chemical characterisation of smoke particles. Here, emission factors for carbon oxides (CO2 and CO), total hydrocarbons (THC), fine (PM2.5) and coarse (PM2.5-10) particles obtained for fires occurring in Portugal in summer 2010 are presented. The carbonaceous content (OC and EC), water-soluble ions, elements and organic composition of smoke particles were, respectively, analysed by a thermal-optical transmission technique, ion chromatography, instrumental neutron activation analysis (INAA) and gas chromatography-mass spectrometry (GC-MS). The particle mass concentrations were in the ranges 0.69-25 mg m-3 for PM2.5 and 0.048-3.1 mg m-3 for PM2.5-10. PM2.5 particles represented 91 ± 5.7% of the PM10 mass. The OC/EC ratios in fine and coarse particles ranged from 2.5 to 205 and from 1.7 to 328, respectively. The water-soluble ions represented, on average, 3.9% and 2.8% of PM2.5 and PM2.5-10 mass, respectively. In general, the dominant ions in the water extracts were Na+, NH4+, Cl- and NO3- for the PM2.5 fraction, and K+, Mg2+, Ca2+ and SO42- for the PM2.5-10 fraction. The K+/EC and K+/OC ratios obtained in this study were, on average, 0.22 ± 0.23 and 0.011 ± 0.014 for PM2.5 and 0.83 ± 1.0 and 0.024 ± 0.023 for PM2.5-10 particles, respectively. The K+/levoglucosan ratio was, on average, 2.0 for PM2.5 and 3.1 for PM2.5-10 particles. Levoglucosan was detected at mass fractions of 1.6-8.7 mg g-1 OC in PM2.5 and 2.7-56 mg g-1 OC in PM2.5-10. The dominant elements detected in the smoke samples were Na, Br, Cr, Fe, K, Rb and Zn. The most representative organic constituents in the smoke samples were acids, alcohols, terpenoid-type compounds, sugars and phenols, in both size fractions.

  13. Single Particle Source Profiles of Gasoline and Diesel Powered Vehicles, Biomass Burning and Coal Combustion Exhaust Emissions

    NASA Astrophysics Data System (ADS)

    Suess, D. T.; Prather, K. A.; Schauer, J.; Cass, G. R.

    2001-12-01

    Vehicular exhaust, biomass burning, and coal combustion are three significant aerosol sources that have local to global impacts on the earth's atmosphere. They may also contribute to health effects as they can emit carcinogenic species such as polycyclic aromatic hydrocarbons (PAH) and trace metals including beryllium and vanadium. In these source characterization studies, combustion products were diluted to near ambient temperature and pressure using a two stage dilution source sampler. Diluted exhaust emissions were analyzed with an aerosol time-of-flight mass spectrometer (ATOFMS) obtaining real-time measurements of single particle size and chemical composition. In addition, samples were collected using a micro-orifice uniform deposit impactor (MOUDI), which was operated in a manner compatible with advanced chemical analysis techniques, for size segregated mass concentrations. Due to the importance of these particle sources to the atmosphere, differentiating these emissions from each other and other particle sources is essential. Since ATOFMS is a relatively new single particle analysis technique, source characterization experiments are needed to determine qualitative signatures of specific particulate sources for their ambient identification. ATOFMS single particle mass spectra will be discussed introducing chemically distinct single particle types emitted from these combustion sources. Numerous particle types are emitted from each source, as indicated by distinct chemical associations on the single particle level. Examples include, the chemical associations of vanadium with organic carbon (OC) in gasoline powered vehicle emissions, calcium with black carbon (BC) in diesel powered vehicle emissions, beryllium and boron with BC in coal combustion emissions, and potassium with OC from biomass burning emissions. Most importantly, the overall particle type distributions from each source differ significantly. Finally, complementary MOUDI mass distribution data will

  14. Acoustic emission during fatigue crack propagation in SiC particle reinforced Al matrix composites

    SciTech Connect

    Niklas, A.; Froyen, L.; Wevers, M.; Delaey, L.

    1995-12-01

    The acoustic emission (AE) behavior during fatigue propagation in aluminum 6061 and aluminum 6061 matrix composites containing 5, 10, and 20 wt pct SiC particle reinforcement was investigated under tension-tension fatigue loading. The purpose of this investigation was to monitor fatigue crack propagation by the AE technique and to identify the source(s) of AE. Most of the AEs detected were observed at the top of the load cycles. The cumulative number of AE events was found to correspond closely to the fatigue crack growth and to increase with increasing SiC content. Fractographic studies revealed an increasing number of fractured particles and to a lesser extent decohered particles on the fatigue fracture surface as the crack propagation rate (e.g., {Delta}K) or the SiC content was increased.

  15. Neighborhood-scale air quality impacts of emissions from motor vehicles and aircraft

    NASA Astrophysics Data System (ADS)

    Choi, Wonsik; Hu, Shishan; He, Meilu; Kozawa, Kathleen; Mara, Steve; Winer, Arthur M.; Paulson, Suzanne E.

    2013-12-01

    A mobile monitoring platform (MMP) was used to measure real-time air pollutant concentrations in different built environments of Boyle Heights (BH, a lower-income community enclosed by several freeways); Downtown Los Angeles (DTLA, adjacent to BH with taller buildings and surrounded by several freeways); and West Los Angeles (WLA, an affluent community traversed by two freeways) in summer afternoons of 2008 and 2011 (only for WLA). Significant inter-community and less significant but observable intra-community differences in traffic-related pollutant concentrations were observed both in the residential neighborhoods studied and on their arterial roadways between BH, DTLA, and WLA, particularly for ultrafine particles (UFP). HEV, defined as vehicles creating plumes with concentrations more than three standard deviations from the adjusted local baseline, were encountered during 6-13% of sampling time, during which they accounted for 17-55% of total UFP concentrations both on arterial roadways and in residential neighborhoods. If instead a single threshold value is used to define HEVs in all areas, HEV's were calculated to make larger contributions to UFP concentrations in BH than other communities by factors of 2-10 or more. Santa Monica Airport located in WLA appears to be a significant source for elevated UFP concentrations in nearby residential neighborhoods 80-400 m downwind. In the WLA area, we also showed, on a neighborhood scale, striking and immediate reductions in particulate pollution (˜70% reductions in both UFP and, somewhat surprisingly, PM2.5), corresponding to dramatic decreases in traffic densities during an I-405 closure event (“Carmageddon”) compared to non-closure Saturday levels. Although pollution reduction due to decreased traffic is not unexpected, this dramatic improvement in particulate pollution provides clear evidence air quality can be improved through strategies such as heavy-duty-diesel vehicle retrofits, earlier retirement of HEV

  16. Estimating Bacteria Emissions from Inversion of Atmospheric Transport: Sensitivity to Modelled Particle Characteristics

    SciTech Connect

    Burrows, Susannah M.; Rayner, Perter; Butler, T.; Lawrence, M.

    2013-06-04

    Model-simulated transport of atmospheric trace components can be combined with observed concentrations to obtain estimates of ground-based sources using various inversion techniques. These approaches have been applied in the past primarily to obtain source estimates for long-lived trace gases such as CO2. We consider the application of similar techniques to source estimation for atmospheric aerosols, by using as a case study the estimation of bacteria emissions from different ecosystem regions in the global atmospheric chemistry and climate model ECHAM5/MESSy-Atmospheric Chemistry (EMAC). Simulated particle concentrations in the tropopause region and at high latitudes, as well as transport of particles to tundra and land ice regions are shown to be highly sensitive to scavenging in mixed-phase clouds, which is poorly characterized in most global climate models. This may be a critical uncertainty in correctly simulating the transport of aerosol particles to the Arctic. Source estimation via Monte Carlo Markov Chain is applied to a suite of sensitivity simulations and the global mean emissions are estimated. We present an analysis of the partitioning of uncertainties in the global mean emissions that are attributable to particle size, CCN activity, the ice nucleation scavenging ratios for mixed-phase and cold clouds, and measurement error. Uncertainty due to CCN activity or to a 1 um error in particle size is typically between 10% and 40% of the uncertainty due to data uncertainty, as measured by the 5%-ile to 95%-ile range of the Monte Carlo ensemble. Uncertainty attributable to the ice nucleation scavenging ratio in mized-phase clouds is as high as 10% to 20% of the data uncertainty. Taken together, the four model 20 parameters examined contribute about half as much to the uncertainty in the estimated