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Sample records for aircraft exhaust plume

  1. Ion recombination in aircraft exhaust plumes

    NASA Astrophysics Data System (ADS)

    Sorokin, A.; Mirabel, P.

    In this article, a model which examines the evolution of ion concentrations in a hot aircraft exhaust plume on the ground is proposed. The model includes plume dilution and ion-ion recombination with coefficients which vary with temperature. A comparison of the model is made with the available ground-based experimental data obtained on the ATTAS research aircraft engines. From this comparison, an ion emission index of the order of 8 1016 ions/kg(fuel) inferred.

  2. Stratospheric aircraft exhaust plume and wake chemistry

    NASA Technical Reports Server (NTRS)

    Miake-Lye, R. C.; Martinez-Sanchez, M.; Brown, R. C.; Kolb, C. E.; Worsnop, D. R.; Zahniser, M. S.; Robinson, G. N.; Rodriguez, J. M.; Ko, M. K. W.; Shia, R-L.

    1993-01-01

    Progress to date in an ongoing study to analyze and model emissions leaving a proposed High Speed Civil Transport (HSCT) from when the exhaust gases leave the engine until they are deposited at atmospheric scales in the stratosphere is documented. A kinetic condensation model was implemented to predict heterogeneous condensation in the plume regime behind an HSCT flying in the lower stratosphere. Simulations were performed to illustrate the parametric dependence of contrail droplet growth on the exhaust condensation nuclei number density and size distribution. Model results indicate that the condensation of water vapor is strongly dependent on the number density of activated CN. Incorporation of estimates for dilution factors into a Lagrangian box model of the far-wake regime with scale-dependent diffusion indicates negligible decrease in ozone and enhancement of water concentrations of 6-13 times background, which decrease rapidly over 1-3 days. Radiative calculations indicate a net differential cooling rate of the plume about 3K/day at the beginning of the wake regime, with a total subsidence ranging between 0.4 and 1 km. Results from the Lagrangian plume model were used to estimate the effect of repeated superposition of aircraft plumes on the concentrations of water and NO(y) along a flight corridor. Results of laboratory studies of heterogeneous chemistry are also described. Kinetics of HCl, N2O5 and ClONO2 uptake on liquid sulfuric acid were measured as a function of composition and temperature. Refined measurements of the thermodynamics of nitric acid hydrates indicate that metastable dihydrate may play a role in the nucleation of more stable trihydrates PSC's.

  3. Hyper-spectral imaging of aircraft exhaust plumes

    NASA Astrophysics Data System (ADS)

    Bowen, Spencer; Bradley, Kenneth; Gross, Kevin; Perram, Glen; Marciniak, Michael

    2008-10-01

    An imaging Fourier-transform spectrometer has been used to determine low spatial resolution temperature and chemical species concentration distributions of aircraft jet engine exhaust plumes. An overview of the imaging Fourier transform spectrometer and the methodology of the project is presented. Results to date are shared and future work is discussed. Exhaust plume data from a Turbine Technologies, LTD, SR-30 turbojet engine at three engine settings was collected using a Telops Field-portable Imaging Radiometric Spectrometer Technology Mid-Wave Extended (FIRST-MWE). Although the plume exhibited high temporal frequency fluctuations, temporal averaging of hyper-spectral data-cubes produced steady-state distributions, which, when co-added and Fourier transformed, produced workable spectra. These spectra were then reduced using a simplified gaseous effluent model to fit forward-modeled spectra obtained from the Line-By-Line Radiative Transfer Model (LBLRTM) and the high-resolution transmission (HITRAN) molecular absorption database to determine approximate temperature and concentration distributions. It is theorized that further development of the physical model will produce better agreement between measured and modeled data.

  4. Dynamics of aircraft exhaust plumes in the jet-regime

    NASA Astrophysics Data System (ADS)

    Kärcher, B.; Fabian, P.

    1994-10-01

    A computational model describing the two-dimensional, turbulent mixing of a single jet of exhaust gas from aircraft engines with the ambient atmosphere is presented. The underlying assumptions and governing equations are examined and supplemented by a discussion of analytical solutions. As an application, the jet dynamics of a B747-400 aircraft engine in cruise and its dependence on key parameters is investigated in detail. The computer code for this dynamical model is computationally fast and can easily be coupled to complex chemical and microphysical models in order to perform comprehensive studies of atmospheric effects from aircraft exhaust emissions in the jet regime.

  5. Abatement of an aircraft exhaust plume using aerodynamic baffles.

    PubMed

    Bennett, Michael; Christie, Simon M; Graham, Angus; Garry, Kevin P; Velikov, Stefan; Poll, D Ian; Smith, Malcolm G; Mead, M Iqbal; Popoola, Olalekan A M; Stewart, Gregor B; Jones, Roderic L

    2013-03-01

    The exhaust jet from a departing commercial aircraft will eventually rise buoyantly away from the ground; given the high thrust/power (i.e., momentum/buoyancy) ratio of modern aero-engines, however, this is a slow process, perhaps requiring ∼ 1 min or more. Supported by theoretical and wind tunnel modeling, we have experimented with an array of aerodynamic baffles on the surface behind a set of turbofan engines of 124 kN thrust. Lidar and point sampler measurements show that, as long as the intervention takes place within the zone where the Coanda effect holds the jet to the surface (i.e., within about 70 m in this case), then quite modest surface-mounted baffles can rapidly lift the jet away from the ground. This is of potential benefit in abating both surface concentrations and jet blast downstream. There is also some modest acoustic benefit. By distributing the aerodynamic lift and drag across an array of baffles, each need only be a fraction of the height of a single blast fence. PMID:23343109

  6. Computational models for the viscous/inviscid analysis of jet aircraft exhaust plumes. [predicting afterbody drag

    NASA Technical Reports Server (NTRS)

    Dash, S. M.; Pergament, H. S.; Thorpe, R. D.

    1980-01-01

    Computational models which analyze viscous/inviscid flow processes in jet aircraft exhaust plumes are discussed. These models are component parts of an NASA-LaRC method for the prediction of nozzle afterbody drag. Inviscid/shock processes are analyzed by the SCIPAC code which is a compact version of a generalized shock capturing, inviscid plume code (SCIPPY). The SCIPAC code analyzes underexpanded jet exhaust gas mixtures with a self-contained thermodynamic package for hydrocarbon exhaust products and air. A detailed and automated treatment of the embedded subsonic zones behind Mach discs is provided in this analysis. Mixing processes along the plume interface are analyzed by two upgraded versions of an overlaid, turbulent mixing code (BOAT) developed previously for calculating nearfield jet entrainment. The BOATAC program is a frozen chemistry version of BOAT containing the aircraft thermodynamic package as SCIPAC; BOATAB is an afterburning version with a self-contained aircraft (hydrocarbon/air) finite-rate chemistry package. The coupling of viscous and inviscid flow processes is achieved by an overlaid procedure with interactive effects accounted for by a displacement thickness type correction to the inviscid plume interface.

  7. Remote measurement of the plume shape of aircraft exhausts at airports by passive FTIR spectrometry

    NASA Astrophysics Data System (ADS)

    Schafer, Klaus; Jahn, Carsten; Utzig, Selina; Flores-Jardines, Edgar; Harig, Roland; Rusch, Peter

    2004-11-01

    Information about the interaction between the exhaust plume of an aircraft jet engine and ambient air is required for the application of small-scale chemistry-transport models to investigate airport air quality. This interaction is not well understood. In order to study the interaction, spatial information about the plume is required. FTIR emission spectroscopy may be applied to analyze the aircraft exhausts. In order to characterize the plumes spatially, a scanning imaging FTIR system (SIGIS) has been improved. SIGIS is comprised of an interferometer (Bruker OPAG), an azimuth-elevation-scanning mirror, a data acquisition and control system with digital signal processors (DSP), an infrared camera and a personal computer. With this instrumentation it is possible to visualise the plume and to obtain information about the temperature distribution within the plume. Measurements are performed at low spectral resolution, because the dynamic environment of these measurements limits the measurement time to about 2 minutes. Measurements of the plume shapes of an APU and of main engines were performed.

  8. Stratospheric aircraft exhaust plume and wake chemistry studies

    NASA Technical Reports Server (NTRS)

    Miake-Lye, R. C.; Martinez-Sanchez, M.; Brown, R. C.; Kolb, C. E.; Worsnop, D. R.; Zahniser, M. S.; Robinson, G. N.; Rodriguez, J. M.; Ko, M. K. W.; Shia, R-L.

    1992-01-01

    This report documents progress to date in an ongoing study to analyze and model emissions leaving a proposed High Speed Civil Transport (HSCT) from when the exhaust gases leave the engine until they are deposited at atmospheric scales in the stratosphere. Estimates are given for the emissions, summarizing relevant earlier work (CIAP) and reviewing current propulsion research efforts. The chemical evolution and the mixing and vortical motion of the exhaust are analyzed to track the exhaust and its speciation as the emissions are mixed to atmospheric scales. The species tracked include those that could be heterogeneously reactive on the surfaces of the condensed solid water (ice) particles and on exhaust soot particle surfaces. Dispersion and reaction of chemical constituents in the far wake are studied with a Lagrangian air parcel model, in conjunction with a radiation code to calculate the net heating/cooling. Laboratory measurements of heterogeneous chemistry of aqueous sulfuric acid and nitric acid hydrates are also described. Results include the solubility of HCl in sulfuric acid which is a key parameter for modeling stratospheric processing. We also report initial results for condensation of nitric acid trihydrate from gas phase H2O and HNO3.

  9. In situ observations in aircraft exhaust plumes in the lower stratosphere at midlatitudes

    NASA Technical Reports Server (NTRS)

    Fahey, D. W.; Keim, E. R.; Woodbridge, E. L.; Gao, R. S.; Boering, K. A.; Daube, B. C.; Wofsy, S. C.; Lohmann, R. P.; Hintsa, E. J.; Dessler, A. E.

    1995-01-01

    Instrumentation on the NASA ER-2 high-altitude aircraft has been used to observe engine exhaust from the same aircraft while operating in the lower stratosphere. Encounters with the exhaust plume occurred approximately 10 min after emission with spatial scales near 2 km and durations of up to 10 s. Measurements include total reactive nitrogen, NO(y), the component species NO and NO2, CO2, H2O, CO, N2O, condensation nuclei, and meteorological parameters. The integrated amounts of CO2 and H2O during the encounters are consistent with the stoichiometry of fuel combustion (1:1 molar). Emission indices (EI) for NO(x) (= NO + NO2), CO, and N2O are calculated using simultaneous measurements of CO2. EI values for NO(x) near 4 g/(kg fuel) are in good agreement with values scaled from limited ground-based tests of the ER-2 engine. Non-NO(x) species comprise less than about 20% of emitted reactive nitrogen, consistent with model evaluations. In addition to demonstrating the feasibility of aircraft plume detection, these results increase confidence in the projection of emissions from current and proposed supersonic aircraft fleets and hence in the assessment of potential long-term changes in the atmosphere.

  10. Measurements of HONO, NO, NOy and SO2 in aircraft exhaust plumes at cruise

    NASA Astrophysics Data System (ADS)

    Jurkat, T.; Voigt, C.; Arnold, F.; Schlager, H.; Kleffmann, J.; Aufmhoff, H.; Schäuble, D.; Schaefer, M.; Schumann, U.

    2011-05-01

    Measurements of gaseous nitrogen and sulfur oxide emissions in young aircraft exhaust plumes give insight into chemical oxidation processes inside aircraft engines. Particularly, the OH-induced formation of nitrous acid (HONO) from nitrogen oxide (NO) and sulfuric acid (H2SO4) from sulfur dioxide (SO2) inside the turbine which is highly uncertain, need detailed analysis to address the climate impact of aviation. We report on airborne in situ measurements at cruise altitudes of HONO, NO, NOy, and SO2 in 9 wakes of 8 different types of modern jet airliners, including for the first time also an A380. Measurements of HONO and SO2 were made with an ITCIMS (Ion Trap Chemical Ionization Mass Spectrometer) using a new ion-reaction scheme involving SF5- reagent ions. The measured molar ratios HONO/NO and HONO/NOy with averages of 0.038 ± 0.010 and 0.027 ± 0.005 were found to decrease systematically with increasing NOx emission-index (EI NOx). We calculate an average EI HONO of 0.31 ± 0.12 g NO2 kg-1. Using reliable measurements of HONO and NOy, which are less adhesive than H2SO4 to the inlet walls, we derive the OH-induced conversion fraction of fuel sulfur to sulfuric acid $\\varepsilon$ with an average of 2.2 ± 0.5 %. $\\varepsilon$ also tends to decrease with increasing EI NOx, consistent with earlier model simulations. The lowest HONO/NO, HONO/NOy and $\\varepsilon$ was observed for the largest passenger aircraft A380.

  11. Effects of plume-scale versus grid-scale treatment of aircraft exhaust photochemistry

    NASA Astrophysics Data System (ADS)

    Cameron, Mary A.; Jacobson, Mark Z.; Naiman, Alexander D.; Lele, Sanjiva K.

    2013-11-01

    is a study to examine the impact of modeling photochemistry from aircraft emissions in an expanding plume versus at the grid scale in an atmospheric model. Differences in model treatments for a single flight occurred at all altitudes during takeoff, cruise, and landing. After 10 h, the plume treatment decreased grid-scale ozone production by 33%, methane destruction by 30%, and carbon monoxide destruction by 32% at cruise altitude compared with the grid-scale treatment. The plume treatment changed the odd nitrogen partitioning by ~10%. For multiple overlapping flights at cruise altitude, final ozone, methane, and carbon monoxide perturbations decreased by 77, 68, and 74%, respectively, compared with the grid-scale treatment. Enhanced mixing with ambient air reduced the plume-scale and grid-scale differences. The persistent differences in photochemical activity indicate that individual plume treatment should be incorporated into 3-D modeling studies.

  12. Sulfuric acid measurements in the exhaust plume of a jet aircraft in flight: Implications for the sulfuric acid formation efficiency

    NASA Astrophysics Data System (ADS)

    Curtius, J.; Arnold, F.; Schulte, P.

    2002-04-01

    Sulfuric acid concentrations were measured in the exhaust plume of a B737-300 aircraft in flight. The measurements were made onboard of the German research aircraft Falcon using the Volatile Aerosol Component Analyzer (VACA). The VACA measures total H2SO4, which is the sum of gaseous H2SO4 and aerosol H2SO4. Measurements took place at distances of 25-200 m behind the B737 corresponding to plume ages of about 0.1-1 seconds. The fuel sulfur content (FSC) of the fuel burned by the B737 engines was alternatively 2.6 and 56 mg sulfur per kilogram fuel (ppmm). H2SO4 concentrations measured in the plume for the 56 ppmm sulfur case were up to ~600 pptv. The average concentration of H2SO4 measured in the ambient atmosphere outside the aircraft plume was 88 pptv, the maximum ambient atmospheric H2SO4 was ~300 pptv. Average efficiencies ɛΔCO2 = 3.3 +/- 1.8% and ɛΔT = 2.9 +/- 1.6% for fuel sulfur conversion to sulfuric acid were inferred when relating the H2SO4 data to measurements of the plume tracers ΔCO2 and ΔT.

  13. Exhaust Nozzle Plume and Shock Wave Interaction

    NASA Technical Reports Server (NTRS)

    Castner, Raymond S.; Elmiligui, Alaa; Cliff, Susan

    2013-01-01

    Fundamental research for sonic boom reduction is needed to quantify the interaction of shock waves generated from the aircraft wing or tail surfaces with the exhaust plume. Both the nozzle exhaust plume shape and the tail shock shape may be affected by an interaction that may alter the vehicle sonic boom signature. The plume and shock interaction was studied using Computational Fluid Dynamics simulation on two types of convergent-divergent nozzles and a simple wedge shock generator. The nozzle plume effects on the lower wedge compression region are evaluated for two- and three-dimensional nozzle plumes. Results show that the compression from the wedge deflects the nozzle plume and shocks form on the deflected lower plume boundary. The sonic boom pressure signature of the wedge is modified by the presence of the plume, and the computational predictions show significant (8 to 15 percent) changes in shock amplitude.

  14. Multispectral imaging of aircraft exhaust

    NASA Astrophysics Data System (ADS)

    Berkson, Emily E.; Messinger, David W.

    2016-05-01

    Aircraft pollutants emitted during the landing-takeoff (LTO) cycle have significant effects on the local air quality surrounding airports. There are currently no inexpensive, portable, and unobtrusive sensors to quantify the amount of pollutants emitted from aircraft engines throughout the LTO cycle or to monitor the spatial-temporal extent of the exhaust plume. We seek to thoroughly characterize the unburned hydrocarbon (UHC) emissions from jet engine plumes and to design a portable imaging system to remotely quantify the emitted UHCs and temporally track the distribution of the plume. This paper shows results from the radiometric modeling of a jet engine exhaust plume and describes a prototype long-wave infrared imaging system capable of meeting the above requirements. The plume was modeled with vegetation and sky backgrounds, and filters were selected to maximize the detectivity of the plume. Initial calculations yield a look-up chart, which relates the minimum amount of emitted UHCs required to detect the presence of a plume to the noise-equivalent radiance of a system. Future work will aim to deploy the prototype imaging system at the Greater Rochester International Airport to assess the applicability of the system on a national scale. This project will help monitor the local pollution surrounding airports and allow better-informed decision-making regarding emission caps and pollution bylaws.

  15. The chemistry and diffusion of aircraft exhausts in the lower stratosphere during the first few hours after fly-by. [with attention to ozone depletion by SST exhaust plumes

    NASA Technical Reports Server (NTRS)

    Hilst, G. R.

    1974-01-01

    An analysis of the hydrogen-nitrogen-oxygen reaction systems in the lower stratosphere as they are initially perturbed by individual aircraft engine exhaust plumes was conducted in order to determine whether any significant chemical reactions occur, either among exhaust chemical species, or between these species and the environmental ozone, while the exhaust products are confined to intact plume segments at relatively high concentrations. The joint effects of diffusive mixing and chemical kinetics on the reactions were also studied, using the techniques of second-order closure diffusion/chemistry models. The focus of the study was on the larger problem of the potential depletion of ozone by supersonic transport aircraft exhaust materials emitted into the lower stratosphere.

  16. Aircraft exhaust sulfur emissions

    NASA Astrophysics Data System (ADS)

    Brown, R. C.; Anderson, M. R.; Miake-Lye, R. C.; Kolb, C. E.; Sorokin, A. A.; Buriko, Y. Y.

    The conversion of fuel sulfur to S(VI) (SO3 + H2SO4) in supersonic and subsonic aircraft engines is estimated numerically. Model results indicate between 2% and 10% of the fuel sulfur is emitted as S(VI). It is also shown that, for a high sulfur mass loading, conversion in the turbine is kinetically limited by the level of atomic oxygen. This results in a higher oxidation efficiency at lower sulfur loadings. SO3 is the primary S(VI) oxidation product and calculated H2SO4 emission levels were less than 1% of the total fuel sulfur. This source of S(VI) can exceed the S(VI) source due to gas phase oxidation in the exhaust wake.

  17. Propagation of light through ship exhaust plumes

    NASA Astrophysics Data System (ADS)

    van Iersel, M.; Mack, A.; van Eijk, A. M. J.; Schleijpen, H. M. A.

    2014-10-01

    Looking through the atmosphere, it is sometimes difficult to see the details of an object. Effects like scintillation and blur are the cause of these difficulties. Exhaust plumes of e.g. a ship can cause extreme scintillation and blur, making it even harder to see the details of what lies behind the plume. Exhaust plumes come in different shapes, sizes, and opaqueness and depending on atmospheric parameters like wind speed and direction, as well as engine settings (power, gas or diesel, etc.). A CFD model is used to determine the plume's flow field outside the stack on the basis of exhaust flow properties, the interaction with the superstructure of the ship, the meteorological conditions and the interaction of ship's motion and atmospheric wind fields. A modified version of the NIRATAM code performs the gas radiation calculations and provides the radiant intensity of the (hot) exhaust gases and the transmission of the atmosphere around the plume is modeled with MODTRAN. This allows assessing the irradiance of a sensor positioned at some distance from the ship and its plume, as function of the conditions that influence the spatial distribution and thermal properties of the plume. Furthermore, an assessment can be made of the probability of detecting objects behind the plume. This plume module will be incorporated in the TNO EOSTAR-model, which provides estimates of detection range and image quality of EO-sensors under varying meteorological conditions.

  18. Infrared Signature Modeling and Analysis of Aircraft Plume

    NASA Astrophysics Data System (ADS)

    Rao, Arvind G.

    2011-09-01

    In recent years, the survivability of an aircraft has been put to task more than ever before. One of the main reasons is the increase in the usage of Infrared (IR) guided Anti-Aircraft Missiles, especially due to the availability of Man Portable Air Defence System (MANPADS) with some terrorist groups. Thus, aircraft IR signatures are gaining more importance as compared to their radar, visual, acoustic, or any other signatures. The exhaust plume ejected from the aircraft is one of the important sources of IR signature in military aircraft that use low bypass turbofan engines for propulsion. The focus of the present work is modelling of spectral IR radiation emission from the exhaust jet of a typical military aircraft and to evaluate the aircraft susceptibility in terms of the aircraft lock-on range due to its plume emission, for a simple case against a typical Surface to Air Missile (SAM). The IR signature due to the aircraft plume is examined in a holistic manner. A comprehensive methodology of computing IR signatures and its affect on aircraft lock-on range is elaborated. Commercial CFD software has been used to predict the plume thermo-physical properties and subsequently an in-house developed code was used for evaluating the IR radiation emitted by the plume. The LOWTRAN code has been used for modeling the atmospheric IR characteristics. The results obtained from these models are in reasonable agreement with some available experimental data. The analysis carried out in this paper succinctly brings out the intricacy of the radiation emitted by various gaseous species in the plume and the role of atmospheric IR transmissivity in dictating the plume IR signature as perceived by an IR guided SAM.

  19. Wedge Shock and Nozzle Exhaust Plume Interaction in a Supersonic Jet Flow

    NASA Technical Reports Server (NTRS)

    Castner, Raymond; Zaman, Khairul; Fagan, Amy; Heath, Christopher

    2014-01-01

    Fundamental research for sonic boom reduction is needed to quantify the interaction of shock waves generated from the aircraft wing or tail surfaces with the nozzle exhaust plume. Aft body shock waves that interact with the exhaust plume contribute to the near-field pressure signature of a vehicle. The plume and shock interaction was studied using computational fluid dynamics and compared with experimental data from a coaxial convergent-divergent nozzle flow in an open jet facility. A simple diamond-shaped wedge was used to generate the shock in the outer flow to study its impact on the inner jet flow. Results show that the compression from the wedge deflects the nozzle plume and shocks form on the opposite plume boundary. The sonic boom pressure signature of the nozzle exhaust plume was modified by the presence of the wedge. Both the experimental results and computational predictions show changes in plume deflection.

  20. Infrared recordings for characterizing an aircraft plume

    NASA Astrophysics Data System (ADS)

    Retief, S. J. P.; Dreyer, M. M.; Brink, C.

    2014-06-01

    Some key electro-optical measurements required to characterize an aircraft plume for automated recognition are shown, as well as some aspects of the processing and use of these measurements. Plume measurements with Short Wavelength Infrared (1.1 - 2.5 um), Mid-Wavelength Infrared (2.5 - 7 um) and Long Wavelength Infrared (7 - 15 um) cameras are presented, as well as spectroradiometer measurements covering the whole Mid-Wavelength, Long Wavelength and upper part of the Short Wavelength Infrared bands. The two limiting factors for the detection of the plume, i.e. the atmospheric transmission bands and the plume emission bands, are discussed, and it is shown how a micro turbine engine can assist in aircraft plume studies. One such a study, regarding the differentiation between an aircraft plume and a blackbody emitter using subbands in the Mid-Wavelength Infrared, is presented. The factors influencing aircraft plume emission are discussed, and the measurements required to characterize an aircraft plume for the purpose of constructing a mathematical plume model are indicated. Since the required measurements are prescribed by the plume model requirements, a brief overview of the plume model, that can be used to simulate the results of the plume's emission under different conditions and observation configurations, is given. Such a model can be used to test the robustness of algorithms, like the mentioned subband method, for identifying aircraft plumes. Such a model furthermore enables the simulation of measurements that would be obtained by an electro-optical system, like an infrared seekerhead of a missile, of a plume for the purpose of algorithm training under various simulated environmental conditions.

  1. Impact of aircraft plume dynamics on airport local air quality

    NASA Astrophysics Data System (ADS)

    Barrett, Steven R. H.; Britter, Rex E.; Waitz, Ian A.

    2013-08-01

    Air quality degradation in the locality of airports poses a public health hazard. The ability to quantitatively predict the air quality impacts of airport operations is of importance for assessing the air quality and public health impacts of airports today, of future developments, and for evaluating approaches for mitigating these impacts. However, studies such as the Project for the Sustainable Development of Heathrow have highlighted shortcomings in understanding of aircraft plume dispersion. Further, if national or international aviation environmental policies are to be assessed, a computationally efficient method of modeling aircraft plume dispersion is needed. To address these needs, we describe the formulation and validation of a three-dimensional integral plume model appropriate for modeling aircraft exhaust plumes at airports. We also develop a simplified concentration correction factor approach to efficiently account for dispersion processes particular to aircraft plumes. The model is used to explain monitoring station results in the London Heathrow area showing that pollutant concentrations are approximately constant over wind speeds of 3-12 m s-1, and is applied to reproduce empirically derived relationships between engine types and peak NOx concentrations at Heathrow. We calculated that not accounting for aircraft plume dynamics would result in a factor of 1.36-2.3 over-prediction of the mean NOx concentration (depending on location), consistent with empirical evidence of a factor of 1.7 over-prediction. Concentration correction factors are also calculated for aircraft takeoff, landing and taxi emissions, providing an efficient way to account for aircraft plume effects in atmospheric dispersion models.

  2. Assessment of analytical techniques for predicting solid propellant exhaust plumes and plume impingement environments

    NASA Technical Reports Server (NTRS)

    Tevepaugh, J. A.; Smith, S. D.; Penny, M. M.

    1977-01-01

    An analysis of experimental nozzle, exhaust plume, and exhaust plume impingement data is presented. The data were obtained for subscale solid propellant motors with propellant Al loadings of 2, 10 and 15% exhausting to simulated altitudes of 50,000, 100,000 and 112,000 ft. Analytical predictions were made using a fully coupled two-phase method of characteristics numerical solution and a technique for defining thermal and pressure environments experienced by bodies immersed in two-phase exhaust plumes.

  3. Organic positive ions in aircraft gas-turbine engine exhaust

    NASA Astrophysics Data System (ADS)

    Sorokin, Andrey; Arnold, Frank

    Volatile organic compounds (VOCs) represent a significant fraction of atmospheric aerosol. However the role of organic species emitted by aircraft (as a consequence of the incomplete combustion of fuel in the engine) in nucleation of new volatile particles still remains rather speculative and requires a much more detailed analysis of the underlying mechanisms. Measurements in aircraft exhaust plumes have shown the presence of both different non-methane VOCs (e.g. PartEmis project) and numerous organic cluster ions (MPIK-Heidelberg). However the link between detected organic gas-phase species and measured mass spectrum of cluster ions is uncertain. Unfortunately, up to now there are no models describing the thermodynamics of the formation of primary organic cluster ions in the exhaust of aircraft engines. The aim of this work is to present first results of such a model development. The model includes the block of thermodynamic data based on proton affinities and gas basicities of organic molecules and the block of non-equilibrium kinetics of the cluster ions evolution in the exhaust. The model predicts important features of the measured spectrum of positive ions in the exhaust behind aircraft. It is shown that positive ions emitted by aircraft engines into the atmosphere mostly consist of protonated and hydrated organic cluster ions. The developed model may be explored also in aerosol investigations of the background atmosphere as well as in the analysis of the emission of fine aerosol particles by automobiles.

  4. Monopropellant thruster exhaust plume contamination measurements

    NASA Technical Reports Server (NTRS)

    Baerwald, R. K.; Passamaneck, R. S.

    1977-01-01

    The potential spacecraft contaminants in the exhaust plume of a 0.89N monopropellant hydrazine thruster were measured in an ultrahigh quartz crystal microbalances located at angles of approximately 0 deg, + 15 deg and + or - 30 deg with respect to the nozzle centerline. The crystal temperatures were controlled such that the mass adhering to the crystal surface at temperatures of from 106 K to 256 K could be measured. Thruster duty cycles of 25 ms on/5 seconds off, 100 ms on/10 seconds off, and 200 ms on/20 seconds off were investigated. The change in contaminant production with thruster life was assessed by subjecting the thruster to a 100,000 pulse aging sequence and comparing the before and after contaminant deposition rates. The results of these tests are summarized, conclusions drawn, and recommendations given.

  5. 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.

  6. Implementation of microwave transmissions for rocket exhaust plume diagnostics

    NASA Astrophysics Data System (ADS)

    Coutu, Nicholas George

    Rocket-launched vehicles produce a trail of exhaust that contains ions, free electrons, and soot. The exhaust plume increases the effective conductor length of the rocket. A conductor in the presence of an electric field (e.g. near the electric charge stored within a cloud) can channel an electric discharge. The electrical conductivity of the exhaust plume is related to its concentration of free electrons. The risk of a lightning strike in-flight is a function of both the conductivity of the body and its effective length. This paper presents an approach that relates the electron number density of the exhaust plume to its propagation constant. Estimated values of the collision frequency and electron number density generated from a numerical simulation of a rocket plume are used to guide the design of the experimental apparatus. Test par meters are identified for the apparatus designed to transmit a signal sweep form 4 GHz to 7 GHz through the exhaust plume of a J-class solid rocket motor. Measurements of the scattering parameters imply that the transmission does not penetrate the plume, but instead diffracts around it. The electron density 20 cm downstream from the nozzle exit is estimated to be between 2.7x1014 m--3 and 5.6x10 15 m--3.

  7. Inerting Aircraft Fuel Systems Using Exhaust Gases

    NASA Technical Reports Server (NTRS)

    Hehemann, David G.

    2002-01-01

    Our purpose in this proposal was to determine the feasibility of using carbon dioxide, possibly obtained from aircraft exhaust gases as a substance to inert the fuel contained in fuel tanks aboard aircraft. To do this, we decided to look at the effects carbon dioxide has upon commercial Jet-A aircraft fuel. In particular, we looked at the solubility of CO2 in Jet-A fuel, the pumpability of CO2-saturated Jet-A fuel, the flashpoint of Jet-A fuel under various mixtures of air and CO2, the static outgassing of CO2-Saturated Jet-A fuel and the dynamic outgassing of Jet-A fuel during pumping of Jet-A fuel.

  8. 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.

  9. Infrared Imagery of Solid Rocket Exhaust Plumes

    NASA Technical Reports Server (NTRS)

    Moran, Robert P.; Houston, Janice D.

    2011-01-01

    The Ares I Scale Model Acoustic Test program consisted of a series of 18 solid rocket motor static firings, simulating the liftoff conditions of the Ares I five-segment Reusable Solid Rocket Motor Vehicle. Primary test objectives included acquiring acoustic and pressure data which will be used to validate analytical models for the prediction of Ares 1 liftoff acoustics and ignition overpressure environments. The test article consisted of a 5% scale Ares I vehicle and launch tower mounted on the Mobile Launch Pad. The testing also incorporated several Water Sound Suppression Systems. Infrared imagery was employed during the solid rocket testing to support the validation or improvement of analytical models, and identify corollaries between rocket plume size or shape and the accompanying measured level of noise suppression obtained by water sound suppression systems.

  10. Impact of rocket exhaust plumes on atmospheric composition and climate ― an overview

    NASA Astrophysics Data System (ADS)

    Voigt, Ch.; Schumann, U.; Graf, K.; Gottschaldt, K.-D.

    2013-03-01

    Rockets are the only direct anthropogenic emission sources into the upper atmosphere. Gaseous rocket emissions include CO, N2, H2, H2O, and CO2, while solid rocket motors (SRM) additionally inject significant amounts of aluminum oxide (Al2O3) particles and gaseous chlorine species into the atmosphere. These emissions strongly perturb local atmospheric trace gas and aerosol distributions. Here, previous aircraft measurements in various rocket exhaust plumes including several large space shuttle launch vehicles are compiled. The observed changes of the lower stratospheric composition in the near field are summarized. The injection of chlorine species and particles into the stratosphere can lead to ozone loss in rocket exhaust plumes. Local observations are compared with global model simulations of the effects of rocket emissions on stratospheric ozone concentrations. Large uncertainties remain concerning individual ozone loss reaction rates and the impact of small-scale plume effects on global chemistry. Further, remote sensing data from satellite indicate that rocket exhaust plumes regionally increase iron and water vapor concentrations in the mesosphere potentially leading to the formation of mesospheric clouds at 80- to 90-kilometer altitude. These satellite observations are summarized and the rocket emission inventory is compared with other natural and anthropogenic sources to the stratosphere such as volcanism, meteoritic material, and aviation.

  11. Modeling Macro- and Micro-Scale Turbulent Mixing and Chemistry in Engine Exhaust Plumes

    NASA Technical Reports Server (NTRS)

    Menon, Suresh

    1998-01-01

    Simulation of turbulent mixing and chemical processes in the near-field plume and plume-vortex regimes has been successfully carried out recently using a reduced gas phase kinetics mechanism which substantially decreased the computational cost. A detailed mechanism including gas phase HOx, NOx, and SOx chemistry between the aircraft exhaust and the ambient air in near-field aircraft plumes is compiled. A reduced mechanism capturing the major chemical pathways is developed. Predictions by the reduced mechanism are found to be in good agreement with those by the detailed mechanism. With the reduced chemistry, the computer CPU time is saved by a factor of more than 3.5 for the near-field plume modeling. Distributions of major chemical species are obtained and analyzed. The computed sensitivities of major species with respect to reaction step are deduced for identification of the dominant gas phase kinetic reaction pathways in the jet plume. Both the near field plume and the plume-vortex regimes were investigated using advanced mixing models. In the near field, a stand-alone mixing model was used to investigate the impact of turbulent mixing on the micro- and macro-scale mixing processes using a reduced reaction kinetics model. The plume-vortex regime was simulated using a large-eddy simulation model. Vortex plume behind Boeing 737 and 747 aircraft was simulated along with relevant kinetics. Many features of the computed flow field show reasonable agreement with data. The entrainment of the engine plumes into the wing tip vortices and also the partial detrainment of the plume were numerically captured. The impact of fluid mechanics on the chemical processes was also studied. Results show that there are significant differences between spatial and temporal simulations especially in the predicted SO3 concentrations. This has important implications for the prediction of sulfuric acid aerosols in the wake and may partly explain the discrepancy between past numerical studies

  12. Rocket exhaust plume impingement on the Voyager spacecraft

    NASA Technical Reports Server (NTRS)

    Baerwald, R. K.

    1978-01-01

    In connection with the conduction of the long-duration Voyager missions to the outer planets and the sophisticated propulsion systems required, it was necessary to carry out an investigation to avoid exhaust plume impingement problems. The rarefied gas dynamics literature indicates that, for most engineering surfaces, the assumption of diffuse reemission and complete thermal accommodation is warranted in the free molecular flow regime. This assumption was applied to an analysis of a spacecraft plume impingement problem in the near-free molecular flow regime and yielded results to within a few percent of flight data. The importance of a correct treatment of the surface temperature was also demonstrated. Specular reflection, on the other hand, was shown to yield results which may be unconservative by a factor of 2 or 3. It is pointed out that one of the most difficult portions of an exhaust plume impingement analysis is the simulation of the impinged hardware. The geometry involved must be described as accurately and completely as possible.

  13. Small- and medium-scale effects of high-flying aircraft exhausts on the atmospheric composition

    NASA Astrophysics Data System (ADS)

    Karol, I. L.; Ozolin, Y. E.

    1994-10-01

    Following numerous model studies of the global impacts of sub- and supersonic aircraft on the atmosphere, this paper assesses the separate aircraft engine exhaust effects of the 45°N cruise flight and at the 10- and 18-km levels of the July atmosphere. A box diffusion photochemical model in the cross-section plane of the flight trajectory is used to compute the effects of gas-phase and heterogeneous reactions on the condensation trail particles in the troposphere, and on the sulphate aerosols in the stratosphere. The enhanced horizontal dispersion of the exhaust plume is considered in the model. A significant but short term depletion of ozone is predicted, which is 99% restored in about 1 h in the wide plume with enhanced horizontal dispersion, but requires more than 24 h in the narrow plume without it. The oxidation rate of NO and NO2 into the HNO3 depends on the OH content in the exhausts and varies in all the cases. The heterogeneous photochemistry has only a small influence on the initial evolution of N2O5 and HO2 in the plume.

  14. Exhaust Plume Measurements of the VASIMR VX-200

    NASA Astrophysics Data System (ADS)

    Longmier, Benjamin; Bering, Edgar, III; Squire, Jared; Glover, Tim; Chang-Diaz, Franklin; Brukardt, Michael

    2008-11-01

    Recent progress is discussed in the development of an advanced RF electric propulsion concept: the Variable Specific Impulse Magnetoplasma Rocket (VASIMR) VX-200 engine, a 200 kW flight-technology prototype. Results from high power Helicon only and Helicon with ICRH experiments are performed on the VX-200 using argon plasma. Recent measurements of axial plasma density and potential profiles, magnetic field-line shaping, charge exchange, and force measurements taken in the plume of the VX-200 exhaust are made within a new 125 cubic meter cryo-pumped vacuum chamber and are presented in the context of RF plasma thruster physics.

  15. Environmental Effects of Space Shuttle Solid Rocket Motor Exhaust Plumes

    NASA Technical Reports Server (NTRS)

    Hwang, B.; Pergament, H. S.

    1976-01-01

    The deposition of NOx and HCl in the stratosphere from the space shuttle solid rocket motors (SRM) and exhaust plume is discussed. A detailed comparison between stratospheric deposition rates using the baseline SRM propellant and an alternate propellant, which replaces ammonium perchlorate by ammonium nitrate, shows the total NOx deposition rate to be approximately the same for each propellant. For both propellants the ratio of the deposition rates of NOx to total chlorine-containing species is negligibly small. Rocket exhaust ground cloud transport processes in the troposphere are also examined. A brief critique of the multilayer diffusion models (presently used for predicting pollutant deposition in the troposphere) is presented, and some detailed cloud rise calculations are compared with data for Titan 3C launches. The results show that, when launch time meteorological data are used as input, the model can reasonably predict measured cloud stabilization heights.

  16. Species separation in rocket exhaust plumes and analytic plume flow models

    NASA Astrophysics Data System (ADS)

    Koppenwallner, G.

    2001-08-01

    Species separation in the exhaust plume of control thrusters of satellites is of main importance for the contamination analysis. Contamination concerns mainly scientific instruments or sensitive surfaces.. In continuum fluid dynamics a multi- component gas mixture can be treated as mixture with mean properties and with a flow field independent composition. This basic feature of continuum flow ceases to be valid in the rarefied flow regimes. In this regime there are two main mechanism which cause a separation of species in the flow field. a. Strong velocity gradients or streamline curvature. Strong stream line curvatures with large centrifugal forces exist close to the nozzle throat of sonic free jets [Sherman] or at the nozzle lip. Heavy gas constituents will not be able to follow these strong stream line curvatures. b. Different thermal velocity or thermal diffusivity of heavy and light gas constituents The transition from continuum to free molecular plume expansion can approximately be described by the sudden freeze model of Bird. At the freezing point molecular collisions suddenly cease and the further expansion is given by the velocity vector of the individual molecules at this freezing point. As light molecules have a larger thermal speed c than the heavy ones their spreading potential is also higher. This mechanism will also produce an enrichment of the plume boundary with light molecules. The approaches to model species separation in exhaust plumes as result of the above mechanism will be reviewed. To gain more insight into the separation the following cases are analyzed in detail: [B ]The free molecular supersonic expansion from a freezing plane. □ The various analytic plume flow models and their capability to predict the lateral spreading at the plume boundary (e.g. Simmons, Boynton, Brook, DLR) □ DSMC test case calculations of single and two-species plumes with mass separation. (M. Ivanov, ITAM) Based on this analysis a new 3 region model for species

  17. First Passively-illuminated, High-resolution Polarimetric Images of Exhaust Plumes from Flying Rockets

    NASA Astrophysics Data System (ADS)

    Tyler, D.; Phenis, A.; Mudge, J.; Dank, J.; Tietjen, A.; Hand, D.

    We report video-rate imaging polarimetry observations of boosting rocket exhaust plumes obtained with the Lockheed Martin ATC Simultaneous Stokes Imaging Polarimeter (SSIP). The unique design of the SSIP, mounted to a tracking telescope, allowed us to acquire rocket plume imaging polarimetry over a period of minutes for each of three launches, observing the plume phenomenology at a variety of altitudes and aspect angles. Our data includes image polarimetry of solid and liquid rocket exhaust plumes and mixing of the two exhaust flow fields. We also present multi-spectral image data, showing for the first time distinct shock structures in the plumes at two wavelengths.

  18. Exhaust Nozzle Plume Effects on Sonic Boom Test Results for Isolated Nozzles

    NASA Technical Reports Server (NTRS)

    Castner, Raymond S.

    2011-01-01

    Reducing or eliminating the operational restrictions of supersonic aircraft over populated areas has led to extensive research at NASA. Restrictions were due to the disturbance of the sonic boom, caused by the coalescence of shock waves formed off the aircraft. Recent work has been performed to reduce the magnitude of the sonic boom N-wave generated by airplane components with focus on shock waves caused by the exhaust nozzle plume. Previous Computational Fluid Dynamics (CFD) analysis showed how the shock wave formed at the nozzle lip interacts with the nozzle boat-tail expansion wave. An experiment was conducted in the 1- by 1-ft Supersonic Wind Tunnel at the NASA Glenn Research Center to validate the computational study. Results demonstrated how the nozzle lip shock moved with increasing nozzle pressure ratio (NPR) and reduced the nozzle boat-tail expansion, causing a favorable change in the observed pressure signature. Experimental results were presented for comparison to the CFD results. The strong nozzle lip shock at high values of NPR intersected the nozzle boat-tail expansion and suppressed the expansion wave. Based on these results, it may be feasible to reduce the boat-tail expansion for a future supersonic aircraft with under-expanded nozzle exhaust flow by modifying nozzle pressure or nozzle divergent section geometry.

  19. Aircraft Engine Exhaust Nozzle System for Jet Noise Reduction

    NASA Technical Reports Server (NTRS)

    Thomas, Russell H. (Inventor); Czech, Michael J. (Inventor); Elkoby, Ronen (Inventor)

    2014-01-01

    The aircraft exhaust engine nozzle system includes a fan nozzle to receive a fan flow from a fan disposed adjacent to an engine disposed above an airframe surface of the aircraft, a core nozzle disposed within the fan nozzle and receiving an engine core flow, and a pylon structure connected to the core nozzle and structurally attached with the airframe surface to secure the engine to the aircraft.

  20. Measurements of Unexpected Ozone Loss in a Nighttime Space Shuttle Exhaust Plume: Implications for Geo-Engineering Projects

    NASA Astrophysics Data System (ADS)

    Avallone, L. M.; Kalnajs, L. E.; Toohey, D. W.; Ross, M. N.

    2008-12-01

    Measurements of ozone, carbon dioxide and particulate water were made in the nighttime exhaust plume of the Space Shuttle (STS-116) on 9 December 2006 as part of the PUMA/WAVE campaign (Plume Ultrafast Measurements Acquisition/WB-57F Ascent Video Experiment). The launch took place from Kennedy Space Center at 8:47 pm (local time) on a moonless night and the WB-57F aircraft penetrated the shuttle plume approximately 25 minutes after launch in the lowermost stratosphere. Ozone loss is not predicted to occur in a nighttime Space Shuttle plume since it has long been assumed that the main ozone loss mechanism associated with rocket emissions requires solar photolysis to drive several chlorine-based catalytic cycles. However, the nighttime in situ observations show an unexpected loss of ozone of approximately 250 ppb in the evolving exhaust plume, inconsistent with model predictions. We will present the observations of the shuttle exhaust plume composition and the results of photochemical models of the Space Shuttle plume. We will show that models constrained by known rocket emission kinetics, including afterburning, and reasonable plume dispersion rates, based on the CO2 observations, cannot explain the observed ozone loss. We will propose potential explanations for the lack of agreement between models and the observations, and will discuss the implications of these explanations for our understanding of the composition of rocket emissions. We will describe the potential consequences of the observed ozone loss for long-term damage to the stratospheric ozone layer should geo-engineering projects based on rocket launches be employed.

  1. Stennis Space Center's approach to liquid rocket engine health monitoring using exhaust plume diagnostics

    NASA Technical Reports Server (NTRS)

    Gardner, D. G.; Tejwani, G. D.; Bircher, F. E.; Loboda, J. A.; Van Dyke, D. B.; Chenevert, D. J.

    1991-01-01

    Details are presented of the approach used in a comprehensive program to utilize exhaust plume diagnostics for rocket engine health-and-condition monitoring and assessing SSME component wear and degradation. This approach incorporates both spectral and video monitoring of the exhaust plume. Video monitoring provides qualitative data for certain types of component wear while spectral monitoring allows both quantitative and qualitative information. Consideration is given to spectral identification of SSME materials and baseline plume emissions.

  2. Analysis of Exhaust Plume Effects on Sonic Boom for a 59-Degree Wing Body Model

    NASA Technical Reports Server (NTRS)

    Castner, Raymond S.

    2011-01-01

    Reducing or eliminating the operational restrictions of supersonic aircraft over populated areas has led to extensive research at NASA. Restrictions are due to the disturbance of the sonic boom, caused by the coalescence of shock waves formed off the aircraft. Recent work has been performed to reduce the magnitude of the sonic boom N-wave generated by airplane components with focus on shock waves caused by the exhaust nozzle plume. Previous Computational Fluid Dynamics (CFD) analyses showed how the shock wave formed at the nozzle lip interacted with the nozzle boat-tail expansion wave. The nozzle lip shock moved with increasing nozzle pressure ratio (NPR) and reduced the nozzle boat-tail expansion. Lip shock movement caused a favorable change in the observed pressure signature. These results were applied to a simplified supersonic vehicle geometry with no inlets and no tail, in which the goal was to demonstrate how under-expanded nozzle operation reduced the sonic boom signature by twelve percent. A secondary goal was to demonstrate the use of the Cart3D inviscid code for off-body pressure signatures including the nozzle plume effect.

  3. Hydrazine engine plume contamination mapping. [measuring instruments for rocket exhaust from liquid propellant rocket engines

    NASA Technical Reports Server (NTRS)

    Chirivella, J. E.

    1975-01-01

    Instrumentation for the measurement of plume exhaust specie deposition rates were developed and demonstrated. The instruments, two sets of quartz crystal microbalances, were designed for low temperature operation in the back flow and variable temperature operation in the core flow regions of an exhaust plume. These quartz crystal microbalances performed nominally, and measurements of exhaust specie deposition rates for 8400 number of pulses for a 0.1-lb monopropellant thruster are reported.

  4. 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.

  5. Design of Experiments for Both Experimental and Analytical Study of Exhaust Plume Effects on Sonic Boom

    NASA Technical Reports Server (NTRS)

    Castner, Raymond S.

    2009-01-01

    Computational fluid dynamics (CFD) analysis has been performed to study the plume effects on sonic boom signature for isolated nozzle configurations. The objectives of these analyses were to provide comparison to past work using modern CFD analysis tools, to investigate the differences of high aspect ratio nozzles to circular (axisymmetric) nozzles, and to report the effects of under expanded nozzle operation on boom signature. CFD analysis was used to address the plume effects on sonic boom signature from a baseline exhaust nozzle. Nearfield pressure signatures were collected for nozzle pressure ratios (NPRs) between 6 and 10. A computer code was used to extrapolate these signatures to a ground-observed sonic boom N-wave. Trends show that there is a reduction in sonic boom N-wave signature as NPR is increased from 6 to 10. As low boom designs are developed and improved, there will be a need for understanding the interaction between the aircraft boat tail shocks and the exhaust nozzle plume. These CFD analyses will provide a baseline study for future analysis efforts. For further study, a design of experiments has been conducted to develop a hybrid method where both CFD and small scale wind tunnel testing will validate the observed trends. The CFD and testing will be used to screen a number of factors which are important to low boom propulsion integration, including boat tail angle, nozzle geometry, and the effect of spacing and stagger on nozzle pairs. To design the wind tunnel experiment, CFD was instrumental in developing a model which would provide adequate space to observe the nozzle and boat tail shock structure without interference from the wind tunnel walls.

  6. Remote passive detection of aircraft exhausts at airports

    NASA Astrophysics Data System (ADS)

    Schaefer, Klaus P.; Jahn, Carsten; Harig, Roland; Aleyt, Christian; Rusch, Peter

    Emissions from vented sources are often important inputs for the development of emission inventories and contribute to local air pollution and global enhancement of greenhouse gases. Aircraft engines are part of these emission sources. A passive measurement technique such as FTIR emission spectrometry is more cost effective and faster in operation for the determination of the composition of hot exhausts of this kind than other measurement systems as e.g. in situ techniques. Within the scope of aircraft emission investigations the measurements were performed from a measurement van which is equipped with an FTIR spectrometer of high spectral resolution coupled with a telescope and a two-axis movable mirror for rapid orientation towards the emission sources. At airports the emission indices of CO2, CO and NO of main engines and auxiliary power units of standing aircraft were determined. The measurement time is about one minute. The accuracy is better than 30 % as found from burner experiments with calibration gases (CO and NO). The method is also applied to detect exhausts of flares and smoke stacks. Currently, a new scanning FTIR-system is developed. The system allows imaging of the exhaust gas and rapid automated alignment of the field of view. The goal of the new development is to measure aircraft exhausts during normal operations at the airport. The spectrometer is coupled with a camera giving an image of the scenery so that a rapid selection of the hottest exhaust area is possible. It is planned to equip the system with an infrared camera for automatic tracking of this area with the scanning mirror so that measurements of the exhausts of a moving aircraft are possible.

  7. 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...

  8. Computation of wake/exhaust mixing downstream of advanced transport aircraft

    NASA Technical Reports Server (NTRS)

    Quackenbush, Todd R.; Teske, Milton E.; Bilanin, Alan J.

    1993-01-01

    The mixing of engine exhaust with the vortical wake of high speed aircraft operating in the stratosphere can play an important role in the formation of chemical products that deplete atmospheric ozone. An accurate analysis of this type of interaction is therefore necessary as a part of the assessment of the impact of proposed High Speed Civil Transport (HSCT) designs on atmospheric chemistry. This paper describes modifications to the parabolic Navier-Stokes flow field analysis in the UNIWAKE unified aircraft wake model to accommodate the computation of wake/exhaust mixing and the simulation of reacting flow. The present implementation uses a passive chemistry model in which the reacting species are convected and diffused by the fluid dynamic solution but in which the evolution of the species does not affect the flow field. The resulting analysis, UNIWAKE/PCHEM (Passive CHEMistry) has been applied to the analysis of wake/exhaust flows downstream of representative HSCT configurations. The major elements of the flow field model are described, as are the results of sample calculations illustrating the behavior of the thermal exhaust plume and the production of species important to the modeling of condensation in the wake. Appropriate steps for further development of the UNIWAKE/PCHEM model are also outlined.

  9. In situ measurement of the aerosol size distribution in stratospheric solid rocket motor exhaust plumes

    NASA Astrophysics Data System (ADS)

    Ross, M. N.; Whitefield, P. D.; Hagen, D. E.; Hopkins, A. R.

    The concentration and size distribution of aerosol in the stratospheric exhaust plumes of two Space Shuttle rockets and one Titan IV rocket were measured using a two component aerosol sampling system carried aboard a WB-57F aircraft. Aerosol size distribution in the 0.01 µm to 4 µm diameter size range was measured using a two component sampling system. The measured distributions display a trimodal form with modes near 0.005 µm, 0.09 µm, and 2.03 µm and are used to infer the relative mass fractionation among the three modes. While the smallest mode has been estimated to contain as much as 10% of the total mass of SRM exhaust alumina, we find show that the smallest mode contains less than 0.05% of the alumina mass. This fraction is so small so as to significantly reduce the likelihood that heterogeneous reactions on the SRM alumina surfaces could produce a significant global impact on stratospheric chemistry.

  10. Range safety signal propagation through the SRM exhaust plume of the space shuttle

    NASA Technical Reports Server (NTRS)

    Boynton, F. P.; Davies, A. R.; Rajasekhar, P. S.; Thompson, J. A.

    1977-01-01

    Theoretical predictions of plume interference for the space shuttle range safety system by solid rocket booster exhaust plumes are reported. The signal propagation was calculated using a split operator technique based upon the Fresnel-Kirchoff integral, using fast Fourier transforms to evaluate the convolution and treating the plume as a series of absorbing and phase-changing screens. Talanov's lens transformation was applied to reduce aliasing problems caused by ray divergence.

  11. Exhaust Nozzle Plume Effects on Sonic Boom Test Results for Vectored Nozzles

    NASA Technical Reports Server (NTRS)

    Castner, Raymond

    2012-01-01

    Reducing or eliminating the operational restrictions of supersonic aircraft over populated areas has led to extensive research at NASA. Restrictions were due to the disturbance of the sonic boom, caused by the coalescence of shock waves formed off the aircraft. Recent work has been performed to reduce the magnitude of the sonic boom N-wave generated by airplane components with a focus on shock waves caused by the exhaust nozzle plume. Previous Computational Fluid Dynamics (CFD) analysis showed how the shock wave formed at the nozzle lip interacts with the nozzle boat-tail expansion wave. An experiment was conducted in the 1- by 1-foot Supersonic Wind Tunnel (SWT) at the NASA Glenn Research Center. Results show how the shock generated at the nozzle lip affects the near field pressure signature, and thereby the potential sonic boom contribution for a nozzle at vector angles from 3 to 8 . The experiment was based on the NASA F-15 nozzle used in the Lift and Nozzle Change Effects on Tail Shock experiment, which possessed a large external boat-tail angle. In this case, the large boat-tail angle caused a dramatic expansion, which dominated the near field pressure signature. The impact of nozzle vector angle and nozzle pressure ratio are summarized.

  12. Engine exhaust characteristics evaluation in support of aircraft acoustic testing

    NASA Astrophysics Data System (ADS)

    Ennix, Kimberly A.

    1994-02-01

    NASA Dryden Flight Research Facility and NASA Langley Research Center completed a joint acoustic flight test program. Test objectives were (1) to quantify and evaluate subsonic climb-to-cruise noise and (2) to obtain a quality noise database for use in validating the Aircraft Noise Prediction Program. These tests were conducted using aircraft with engines that represent the high nozzle pressure ratio of future transport designs. Test flights were completed at subsonic speeds that exceeded Mach 0.3 using F-18 and F-16XL aircraft. This paper describes the efforts of NASA Dryden Flight Research Facility in this flight test program. Topics discussed include the test aircraft, setup, and matrix. In addition, the engine modeling codes and nozzle exhaust characteristics are described.

  13. Engine exhaust characteristics evaluation in support of aircraft acoustic testing

    NASA Technical Reports Server (NTRS)

    Ennix, Kimberly A.

    1993-01-01

    NASA Dryden Flight Research Facility and NASA Langley Research Center completed a joint acoustic flight test program. Test objectives were (1) to quantify and evaluate subsonic climb-to-cruise noise and (2) to obtain a quality noise database for use in validating the Aircraft Noise Prediction Program. These tests were conducted using aircraft with engines that represent the high nozzle pressure ratio of future transport designs. Test flights were completed at subsonic speeds that exceeded Mach 0.3 using F-18 and F-16XL aircraft. This paper describes the efforts of NASA Dryden Flight Research Facility in this flight test program. Topics discussed include the test aircraft, setup, and matrix. In addition, the engine modeling codes and nozzle exhaust characteristics are described.

  14. Engine exhaust characteristics evaluation in support of aircraft acoustic testing

    NASA Technical Reports Server (NTRS)

    Ennix, Kimberly A.

    1994-01-01

    NASA Dryden Flight Research Facility and NASA Langley Research Center completed a joint acoustic flight test program. Test objectives were (1) to quantify and evaluate subsonic climb-to-cruise noise and (2) to obtain a quality noise database for use in validating the Aircraft Noise Prediction Program. These tests were conducted using aircraft with engines that represent the high nozzle pressure ratio of future transport designs. Test flights were completed at subsonic speeds that exceeded Mach 0.3 using F-18 and F-16XL aircraft. This paper describes the efforts of NASA Dryden Flight Research Facility in this flight test program. Topics discussed include the test aircraft, setup, and matrix. In addition, the engine modeling codes and nozzle exhaust characteristics are described.

  15. Effect of bipropellant plume exhaust effluents on spaceborne optical instruments

    NASA Astrophysics Data System (ADS)

    Maag, C. R.; Jeffery, J. A.; Millard, J. M.

    1980-01-01

    Analytical tools together with a good data base are necessary to predict the transport of plume contaminants and their effects on spacecraft surfaces. The present paper describes an assessment of bipropellant thrusters, the production and transport of plume contaminants from these thrusters, and the use of the JPL contamination analysis program to assess the effects of plume contamination on the Galileo spacecraft. It is shown that, in the case of the Galileo mission, contamination from the liquid engines has been effectively reduced to nothing by the use of predictive tools. Plume shields together with precise scan platform stowage have been designed to protect the optical instruments.

  16. Zone radiometer measurements on a model rocket exhaust plume

    NASA Technical Reports Server (NTRS)

    1972-01-01

    Radiometer for analytical prediction of rocket plume-to-booster thermal radiation and convective heating is described. Applications for engine combustion analysis, incineration, and pollution control by high temperature processing are discussed. Illustrations of equipment are included.

  17. Modeling the Effects of Aircraft Emissions on Atmospheric Photochemistry Using Layered Plume Dynamics

    NASA Astrophysics Data System (ADS)

    Cameron, M. A.; Jacobson, M. Z.; Naiman, A. D.; Lele, S. K.

    2012-12-01

    Aviation is an expanding industry, experiencing continued growth and playing an increasingly noticed role in upper tropospheric/lower stratospheric composition. Nitrogen oxides and other gas-phase emissions from aircraft react to affect ozone photochemistry. This research investigates the effects of treating aircraft gas-phase chemistry within an expanding layered plume versus at the grid scale. SMVGEAR II, a sparse-matrix, vectorized Gear-type solver for ordinary differential equations, is used to solve chemical equations at both the grid scale and subgrid scale. A Subgrid Plume Model (SPM) is used to advance the expanding plume, accounting for wind shear and diffusion. Simulations suggest that using a layered plume approach results in noticeably different final NOx concentrations, demonstrating the importance of these plume dynamics in predicting the effects of aircraft on ozone concentrations. Results showing the effects of a layered plume, single plume, and no plume on ozone after several hours will be presented.

  18. 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), 2.5E4

  19. Pulse moire interferogram of rocket exhaust plume and its quantitative analysis

    NASA Astrophysics Data System (ADS)

    Miao, Peng C.; Yan, Da P.; Wang, Hai L.; He, An Z.

    1992-01-01

    This paper presented the measurement of the exhaust plume field of solid rocket with a moire interferometer. The principle of the moire interferometer is presented. The moire interferograms of the plume were processed with computer digital image process technique. It was found that the grey distribution of the moire interferograms has a sharp valley, and from the analysis this paper presented a method to thin and trace a deformated moire fringe on one step. This paper presented the result of the quantitative measurement.

  20. A Lagrangian Simulation of Subsonic Aircraft Exhaust Emissions

    NASA Technical Reports Server (NTRS)

    Schoeberl, M. R.; Morris, G. A.

    1999-01-01

    To estimate the effect of subsonic and supersonic aircraft exhaust on the stratospheric concentration of NO(y), we employ a trajectory model initialized with air parcels based on the standard release scenarios. The supersonic exhaust simulations are in good agreement with 2D and 3D model results and show a perturbation of about 1-2 ppbv of NO(y) in the stratosphere. The subsonic simulations show that subsonic emissions are almost entirely trapped below the 380 K potential temperature surface. Our subsonic results contradict results from most other models, which show exhaust products penetrating above 380 K, as summarized. The disagreement can likely be attributed to an excessive vertical diffusion in most models of the strong vertical gradient in NO(y) that forms at the boundary between the emission zone and the stratosphere above 380 K. Our results suggest that previous assessments of the impact of subsonic exhaust emission on the stratospheric region above 380 K should be considered to be an upper bound.

  1. Numerical study on the influence of aluminum on infrared radiation signature of exhaust plume

    NASA Astrophysics Data System (ADS)

    Zhang, Wei; Ye, Qing-qing; Li, Shi-peng; Wang, Ning-fei

    2013-09-01

    The infrared radiation signature of exhaust plume from solid propellant rockets has been widely mentioned for its important realistic meaning. The content of aluminum powder in the propellants is a key factor that affects the infrared radiation signature of the plume. The related studies are mostly on the conical nozzles. In this paper, the influence of aluminum on the flow field of plume, temperature distribution, and the infrared radiation characteristics were numerically studied with an object of 3D quadrate nozzle. Firstly, the gas phase flow field and gas-solid multi phase flow filed of the exhaust plume were calculated using CFD method. The result indicates that the Al203 particles have significant effect on the flow field of plume. Secondly, the radiation transfer equation was solved by using a discrete coordinate method. The spectral radiation intensity from 1000-2400 cm-1 was obtained. To study the infrared radiation characteristics of exhaust plume, an exceptional quadrate nozzle was employed and much attention was paid to the influences of Al203 particles in solid propellants. The results could dedicate the design of the divert control motor in such hypervelocity interceptors or missiles, or be of certain meaning to the improvement of ingredients of solid propellants.

  2. 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.

  3. Towards Simulating Non-Axisymmetric Influences on Aircraft Plumes for Signature Prediction

    NASA Technical Reports Server (NTRS)

    Kenzakowski, D. C.; Shipman, J. D.; Dash, S. M.

    2000-01-01

    A methodology for efficiently including three-dimensional effects on aircraft plume signature is presented. First, exploratory work on the use of passive mixing enhancement devices, namely chevrons and tabs, in IR signature reduction for external turbofan plumes is demonstrated numerically and experimentally. Such small attachments, when properly designed, cause an otherwise axisymmetric plume to have significant 3D structures, affecting signature prediction. Second, an approach for including non-axisymmetric and installation effects in plume signature prediction is discussed using unstructured methodology. Unstructured flow solvers, using advanced turbulence modeling and plume thermochemistry, facilitate the modeling of aircraft effects on plume structure that previously have been neglected due to gridding complexities. The capabilities of the CRUNCH unstructured Navier-Stokes solver for plume modeling is demonstrated for a passively mixed turbofan nozzle, a generic fighter nozzle, and a complete aircraft.

  4. 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

  5. Computational models for the analysis of three-dimensional internal and exhaust plume flowfields

    NASA Technical Reports Server (NTRS)

    Dash, S. M.; Delguidice, P. D.

    1977-01-01

    This paper describes computational procedures developed for the analysis of three-dimensional supersonic ducted flows and multinozzle exhaust plume flowfields. The models/codes embodying these procedures cater to a broad spectrum of geometric situations via the use of multiple reference plane grid networks in several coordinate systems. Shock capturing techniques are employed to trace the propagation and interaction of multiple shock surfaces while the plume interface, separating the exhaust and external flows, and the plume external shock are discretely analyzed. The computational grid within the reference planes follows the trace of streamlines to facilitate the incorporation of finite-rate chemistry and viscous computational capabilities. Exhaust gas properties consist of combustion products in chemical equilibrium. The computational accuracy of the models/codes is assessed via comparisons with exact solutions, results of other codes and experimental data. Results are presented for the flows in two-dimensional convergent and divergent ducts, expansive and compressive corner flows, flow in a rectangular nozzle and the plume flowfields for exhausts issuing out of single and multiple rectangular nozzles.

  6. Factors to Consider in Designing Aerosol Inlet Systems for Engine Exhaust Plume Sampling

    NASA Technical Reports Server (NTRS)

    Anderson, Bruce

    2004-01-01

    This document consists of viewgraphs of charts and diagrams of considerations to take when sampling the engine exhaust plume. It includes a chart that compares the emissions from various fuels, a diagram and charts of the various processes and conditions that influence the particulate size and concentration,

  7. Pseudo Color Densitometer Analysis-the Apollo 17/Saturn V Exhaust Plume.

    PubMed

    Orville, R E; Helsdon, J H

    1974-10-01

    Spectra of the Apollo 17/Saturn V exhaust plume have been obtained in the uv (300ndash;400 nm), visible (400-650 nm), and ir (750-790 nm) regions. Analysis of these data with a pseudo color densitometer reveals (1) a standing wave pattern in the exhaust plume characterized by a wavelength of 9 m, (2) a region of intense continuum within 40 m of the exit plane which supports previous reports of a continuum blackbody source with a peak temperature near 2600 K, (3) a region of continuum emission beyond 40 m that is not blackbody, and (4) line emissions beyond 40 m attributed to the sodium D lines and potassium. It is suggested that an interference filter centered on the sodium D lines could be used on a high speed framing camera to study the turbulent structure of the plume in the nonblackbody region. PMID:20134660

  8. The effects of the exhaust plume on the lightning triggering conditions for launch vehicles

    NASA Technical Reports Server (NTRS)

    Eriksen, Frederick J.; Rudolph, Terence H.; Perala, Rodney A.

    1991-01-01

    Apollo 12 and Atlas Centaur 67 are two launch vehicles that have experienced triggered lightning strikes. Serious consequences resulted from the events; in the case of Atlas Centaur 67, the vehicle and the payload were lost. These events indicate that it is necessary to develop launch rules which would prevent such occurrences. In order to develop valid lightning related rules, it is necessary to understand the effects of the plume. Some have assumed that the plume can be treated as a perfect conductor, and have computed electric field enhancement factors on that basis. The authors have looked at the plume, and believe that these models are not correct, because they ignore the fluid motion of the conducting plates. The authors developed a model which includes this flow character. In this model, the external field is excluded from the plume as it would be for any good conductor, but, in addition, the charge must distribute so that the charge density is zero at some location in the exhaust. When this condition is included in the calculation of triggering enhancement factors, they can be two to three times larger than calculated by other methods which include a conductive plume but don't include the correct boundary conditions. Here, the authors review the relevant features of rocket exhausts for the triggered lightning problem, present an approach for including flowing conductive gases, and present preliminary calculations to demonstrate the effect that the plume has on enhancement factors.

  9. Range safety signal attenuation by the Space Shuttle main engine exhaust plumes

    NASA Technical Reports Server (NTRS)

    Pearce, B. E.

    1983-01-01

    An analysis of attenuation of the range safety signal at 416.5 MHz observed after SRB separation and ending at hand over to Bermuda, during which transmission must pass through the LOX/H2 propelled main engine exhaust plumes, is summarized. Absorption by free electrons in the exhaust plume can account for the nearly constant magnitude of the observed attenuation during this period; it does not explain the short term transient increases that occur at one or more times during this portion of the flight. It is necessary to assume that a trace amount (about 0.5 ppm) of easily ionizable impurity must be present in the exhaust flow. Other mechanisms of attenuation, such as scattering by turbulent fluctuations of both free and bound electrons and absorption by water vapor, were examined but found to be inadequate to explain the observations.

  10. Determination of Combustion Product Radicals in a Hydrocarbon Fueled Rocket Exhaust Plume

    NASA Technical Reports Server (NTRS)

    Langford, Lester A.; Allgood, Daniel C.; Junell, Justin C.

    2007-01-01

    The identification of metallic effluent materials in a rocket engine exhaust plume indicates the health of the engine. Since 1989, emission spectroscopy of the plume of the Space Shuttle Main Engine (SSME) has been used for ground testing at NASA's Stennis Space Center (SSC). This technique allows the identification and quantification of alloys from the metallic elements observed in the plume. With the prospect of hydrocarbon-fueled rocket engines, such as Rocket Propellant 1 (RP-1) or methane (CH4) fueled engines being considered for use in future space flight systems, the contributions of intermediate or final combustion products resulting from the hydrocarbon fuels are of great interest. The effect of several diatomic molecular radicals, such as Carbon Dioxide , Carbon Monoxide, Molecular Carbon, Methylene Radical, Cyanide or Cyano Radical, and Nitric Oxide, needs to be identified and the effects of their band systems on the spectral region from 300 nm to 850 nm determined. Hydrocarbon-fueled rocket engines will play a prominent role in future space exploration programs. Although hydrogen fuel provides for higher engine performance, hydrocarbon fuels are denser, safer to handle, and less costly. For hydrocarbon-fueled engines using RP-1 or CH4 , the plume is different from a hydrogen fueled engine due to the presence of several other species, such as CO2, C2, CO, CH, CN, and NO, in the exhaust plume, in addition to the standard H2O and OH. These species occur as intermediate or final combustion products or as a result of mixing of the hot plume with the atmosphere. Exhaust plume emission spectroscopy has emerged as a comprehensive non-intrusive sensing technology which can be applied to a wide variety of engine performance conditions with a high degree of sensitivity and specificity. Stennis Space Center researchers have been in the forefront of advancing experimental techniques and developing theoretical approaches in order to bring this technology to a more

  11. The effects of an ion-thruster exhaust plume on S-band carrier transmission

    NASA Technical Reports Server (NTRS)

    Ackerknecht, W. E.; Stanton, P. H.

    1976-01-01

    The study reported here was undertaken (1) to develop models of the effects of an ion-thruster exhaust plume on S-band signals, and (2) to measure the effects. The results show that an S-band signal passing through an ion-thruster plume is reduced in amplitude and advanced in phase. The mathematical models gave reasonable estimates of the average signal attenuation and phase shift. Negligible fluctuations in the signal amplitude and phase were measured during steady-state thruster operation. However, large jumps in phase occurred when changes were made in the thruster operating state. This study confirms that the thruster plume can have a significant effect on S-band communication link performance; hence the plume effects must be considered in S-band link calculations when electric thrusters are used for spacecraft propulsion.

  12. Integration of Engine, Plume, and CFD Analyses in Conceptual Design of Low-Boom Supersonic Aircraft

    NASA Technical Reports Server (NTRS)

    Li, Wu; Campbell, Richard; Geiselhart, Karl; Shields, Elwood; Nayani, Sudheer; Shenoy, Rajiv

    2009-01-01

    This paper documents an integration of engine, plume, and computational fluid dynamics (CFD) analyses in the conceptual design of low-boom supersonic aircraft, using a variable fidelity approach. In particular, the Numerical Propulsion Simulation System (NPSS) is used for propulsion system cycle analysis and nacelle outer mold line definition, and a low-fidelity plume model is developed for plume shape prediction based on NPSS engine data and nacelle geometry. This model provides a capability for the conceptual design of low-boom supersonic aircraft that accounts for plume effects. Then a newly developed process for automated CFD analysis is presented for CFD-based plume and boom analyses of the conceptual geometry. Five test cases are used to demonstrate the integrated engine, plume, and CFD analysis process based on a variable fidelity approach, as well as the feasibility of the automated CFD plume and boom analysis capability.

  13. Exhausted Plume Flow Field Prediction Near the Afterbody of Hypersonic Flight Vehicles in High Altitudes

    NASA Technical Reports Server (NTRS)

    Chou, Lynn Chen; Mach, Kervyn D.; Deng, Zheng-Tao; Liaw, Goang-Shin

    1995-01-01

    A two-dimensional computer code to solve the Burnett equations has been developed which computes the flow interaction between an exhausted plume and hypersonic external flow near the afterbody of a flight vehicle. This Burnett-2D code extends the capability of Navier-Stokes solver (RPLUS2D code) to include high-order Burnett source terms and slip-wall conditions for velocity and temperature. Higher-order Burnett viscous stress and heat flux terms are discretized using central-differencing and treated as source terms. Blocking logic is adopted in order to overcome the difficulty of grid generation. The computation of exhaust plume flow field is divided into two steps. In the first step, the thruster nozzle exit conditions are computed which generates inflow conditions in the base area near the afterbody. Results demonstrated that at high altitudes, the computations of nozzle exit conditions must include the effects of base flow since significant expansion exists in the base region. In the second step, Burnett equations were solved for exhaust plume flow field near the afterbody. The free stream conditions are set at an altitude equal to 80km and the Mach number is equal to 5.0. The preliminary results show that the plume expansion, as altitude increases, will eventually cause upstream flow separation.

  14. Exhaust plumes and their interaction with missile airframes - A new viewpoint

    NASA Technical Reports Server (NTRS)

    Dash, S. M.; Sinha, N.

    1992-01-01

    The present, novel treatment of missile airframe-exhaust plume interactions emphasizes their simulation via a formal solution of the Reynolds-averaged Navier-Stokes (RNS) equation and is accordingly able to address the simulation requirements of novel missiles with nonconventional/integrated propulsion systems. The method is made possible by implicit RNS codes with improved artificial dissipation models, generalized geometric capabilities, and improved two-equation turbulence models, as well as by such codes' recent incorporation of plume thermochemistry and multiphase flow effects.

  15. Power-dependent speciation of volatile organic compounds in aircraft exhaust

    NASA Astrophysics Data System (ADS)

    Beyersdorf, Andreas J.; Thornhill, K. Lee; Winstead, Edward L.; Ziemba, Luke D.; Blake, Donald R.; Timko, Michael T.; Anderson, Bruce E.

    2012-12-01

    As part of the third NASA Aircraft Particle Emissions Experiment (APEX-3, November 2005), whole air samples were collected to determine the emission rates of volatile organic compounds (VOCs) from aircraft equipped with three different gas-turbine engines (an Allison Engine 3007-A1E, a Pratt-Whitney 4158, and a Rolls-Royce RB211-535E4B). Samples were collected 1 m behind the engine exhaust plane of the engines while they were operated at powers ranging from idle up to 30% of maximum rated thrust. Exhaust emission indices (mass emitted per kilogram of fuel used) for CO and non-methane hydrocarbons (NMHCs) were calculated based on enhancements over background relative to CO2. Emissions of all NMHCs were greatest at low power with values decreasing by an order of magnitude with increasing power. Previous studies have shown that scaling idle hydrocarbon emissions to formaldehyde or ethene (which are typically emitted at a ratio of 1-to-1 at idle) reduces variability amongst engine types. NMHC emissions were found to scale at low power, with alkenes contributing over 50% of measured NMHCs. However, as the power increases hydrocarbon emissions no longer scale to ethene, as the aromatics become the dominant species emitted. This may be due in part to a shift in combustion processes from thermal cracking (producing predominantly alkenes) to production of new molecules (producing proportionally more aromatics) as power increases. The formation of these aromatics is an intermediate step in the production of soot, which also increases with increasing power. The increase in aromatics relative to alkenes additionally results in a decrease in the hydroxyl radical reactivity and ozone formation potential of aircraft exhaust. Samples collected 30 m downwind of the engine were also analyzed for NMHCs and carbonyl compounds (acetone, 2-butanone and C1-C9 aldehydes). Formaldehyde was the predominant carbonyl emitted; however, the ratio of ethene-to-formaldehyde varied between the

  16. The effect of exhaust plume/afterbody interaction on installed Scramjet performance

    NASA Technical Reports Server (NTRS)

    Edwards, Thomas Alan

    1988-01-01

    Newly emerging aerospace technology points to the feasibility of sustained hypersonic flight. Designing a propulsion system capable of generating the necessary thrust is now the major obstacle. First-generation vehicles will be driven by air-breathing scramjet (supersonic combustion ramjet) engines. Because of engine size limitations, the exhaust gas leaving the nozzle will be highly underexpanded. Consequently, a significant amount of thrust and lift can be extracted by allowing the exhaust gases to expand along the underbody of the vehicle. Predicting how these forces influence overall vehicle thrust, lift, and moment is essential to a successful design. This work represents an important first step toward that objective. The UWIN code, an upwind, implicit Navier-Stokes computer program, has been applied to hypersonic exhaust plume/afterbody flow fields. The capability to solve entire vehicle geometries at hypersonic speeds, including an interacting exhaust plume, has been demonstrated for the first time. Comparison of the numerical results with available experimental data shows good agreement in all cases investigated. For moderately underexpanded jets, afterbody forces were found to vary linearly with the nozzle exit pressure, and increasing the exit pressure produced additional nose-down pitching moment. Coupling a species continuity equation to the UWIN code enabled calculations indicating that exhaust gases with low isentropic exponents (gamma) contribute larger afterbody forces than high-gamma exhaust gases. Moderately underexpanded jets, which remain attached to unswept afterbodies, underwent streamwise separation on upswept afterbodies. Highly underexpanded jets produced altogether different flow patterns, however. The highly underexpanded jet creates a strong plume shock, and the interaction of this shock with the afterbody was found to produce complicated patterns of crossflow separation. Finally, the effect of thrust vectoring on vehicle balance has

  17. Space shuttle exhaust plumes in the lower thermosphere: Advective transport and diffusive spreading

    NASA Astrophysics Data System (ADS)

    Stevens, Michael H.; Lossow, Stefan; Siskind, David E.; Meier, R. R.; Randall, Cora E.; Russell, James M.; Urban, Jo; Murtagh, Donal

    2014-02-01

    The space shuttle main engine plume deposited between 100 and 115 km altitude is a valuable tracer for global-scale dynamical processes. Several studies have shown that this plume can reach the Arctic or Antarctic to form bursts of polar mesospheric clouds (PMCs) within a few days. The rapid transport of the shuttle plume is currently not reproduced by general circulation models and is not well understood. To help delineate the issues, we present the complete satellite datasets of shuttle plume observations by the Sounding of the Atmosphere using Broadband Emission Radiometry instrument and the Sub-Millimeter Radiometer instrument. From 2002 to 2011 these two instruments observed 27 shuttle plumes in over 600 limb scans of water vapor emission, from which we derive both advective meridional transport and diffusive spreading. Each plume is deposited at virtually the same place off the United States east coast so our results are relevant to northern mid-latitudes. We find that the advective transport for the first 6-18 h following deposition depends on the local time (LT) of launch: shuttle plumes deposited later in the day (~13-22 LT) typically move south whereas they otherwise typically move north. For these younger plumes rapid transport is most favorable for launches at 6 and 18 LT, when the displacement is 10° in latitude corresponding to an average wind speed of 30 m/s. For plumes between 18 and 30 h old some show average sustained meridional speeds of 30 m/s. For plumes between 30 and 54 h old the observations suggest a seasonal dependence to the meridional transport, peaking near the beginning of year at 24 m/s. The diffusive spreading of the plume superimposed on the transport is on average 23 m/s in 24 h. The plume observations show large variations in both meridional transport and diffusive spreading so that accurate modeling requires knowledge of the winds specific to each case. The combination of transport and spreading from the STS-118 plume in August

  18. Chemistry in plumes of high-flying aircraft with H 2 combustion engines: a modelling study

    NASA Astrophysics Data System (ADS)

    Weibring, G.; Zellner, R.

    1994-05-01

    . Recent discussions on high-speed civil transport (HSCT) systems have renewed the interest in the chemistry of supersonic-aircraft plumes. The engines of these aircraft emit large concentrations of radicals like O, H, OH, and NO. In order to study the effect of these species on the composition of the atmosphere, the detailed chemistry of an expanding and cooling plume is examined for different expansion models.

  19. Far-Field Turbulent Vortex-Wake/Exhaust Plume Interaction for Subsonic and HSCT Airplanes

    NASA Technical Reports Server (NTRS)

    Kandil, Osama A.; Adam, Ihab; Wong, Tin-Chee

    1996-01-01

    Computational study of the far-field turbulent vortex-wake/exhaust plume interaction for subsonic and high speed civil transport (HSCT) airplanes is carried out. The Reynolds-averaged Navier-Stokes (NS) equations are solved using the implicit, upwind, Roe-flux-differencing, finite-volume scheme. The two-equation shear stress transport model of Menter is implemented with the NS solver for turbulent-flow calculation. For the far-field study, the computations of vortex-wake interaction with the exhaust plume of a single engine of a Boeing 727 wing in a holding condition and two engines of an HSCT in a cruise condition are carried out using overlapping zonal method for several miles downstream. These results are obtained using the computer code FTNS3D. The results of the subsonic flow of this code are compared with those of a parabolized NS solver known as the UNIWAKE code.

  20. Analysis of aircraft exhausts with Fourier-transform infrared emission spectroscopy.

    PubMed

    Heland, J; Schäfer, K

    1997-07-20

    Because of the worldwide growth in air traffic and its increasing effects on the atmospheric environment, it is necessary to quantify the direct aircraft emissions at all altitudes. In this study Fourier-transform infrared emission spectroscopy as a remote-sensing multi-component-analyzing technique for aircraft exhausts was investigated at ground level with a double pendulum interferometer and a line-by-line computer algorithm that was applied to a multilayer radiative transfer problem. Initial measurements were made to specify the spectral windows for traceable compounds, to test the sensitivity of the system, and to develop calibration and continuum handling procedures. To obtain information about the radial temperature and concentration profiles, we developed an algorithm for the analysis of an axial-symmetric multilayered plume by use of the CO(2) hot band at approximately 2400 cm(-1). Measurements were made with several in-service engines. Effects that were due to engine aging were detected but have to be analyzed systematically in the near future. Validation measurements were carried out with a conventional propane gas burner to compare the results with those obtained with standard measurement equipment. These measurements showed good agreement to within +/-20% for the CO and NO(x) results. The overall accuracy of the system was found to be +/-30%. The detection limits of the system for a typical engine plume (380 degrees C, ? = 50 cm) are below 0.1% for CO(2), ~0.7% for H(2)O, ~20 ppmv (parts per million by volume) for CO, and ~90 ppmv for NO. PMID:18259296

  1. Predicting engine parameters using the optic spectrum of the space shuttle main engine exhaust plume

    NASA Astrophysics Data System (ADS)

    Srivastava, Ashok N.; Buntine, Wray

    The Optical Plume Anomaly Detection (OPAD) system is under development to predict engine anomalies and engine parameters of the Space Shuttle's Main Engine (SSME). The anomaly detection is based on abnormal metal concentrations in the optical spectrum of the rocket plume. Such abnormalities could be indicative of engine corrosion or other malfunctions. Here, we focus on the second task of the OPAD system, namely the prediction of engine parameters such as rated power level (RPL) and mixture ratio (MR). Because of the high dimensionality of the spectrum, we developed a linear algorithm to resolve the optical spectrum of the exhaust plume into a number of separate components, each with a different physical interpretation. These components are used to predict the metal concentrations and engine parameters for online support of ground-level testing of the SSME. Currently, these predictions are labor intensive and cannot be done online. We predict RPL using neural networks and give preliminary results.

  2. Temperature, Pressure, and Infrared Image Survey of an Axisymmetric Heated Exhaust Plume

    NASA Technical Reports Server (NTRS)

    Nelson, Edward L.; Mahan, J. Robert; Birckelbaw, Larry D.; Turk, Jeffrey A.; Wardwell, Douglas A.; Hange, Craig E.

    1996-01-01

    The focus of this research is to numerically predict an infrared image of a jet engine exhaust plume, given field variables such as temperature, pressure, and exhaust plume constituents as a function of spatial position within the plume, and to compare this predicted image directly with measured data. This work is motivated by the need to validate computational fluid dynamic (CFD) codes through infrared imaging. The technique of reducing the three-dimensional field variable domain to a two-dimensional infrared image invokes the use of an inverse Monte Carlo ray trace algorithm and an infrared band model for exhaust gases. This report describes an experiment in which the above-mentioned field variables were carefully measured. Results from this experiment, namely tables of measured temperature and pressure data, as well as measured infrared images, are given. The inverse Monte Carlo ray trace technique is described. Finally, experimentally obtained infrared images are directly compared to infrared images predicted from the measured field variables.

  3. Exhaust Plume Effects on Sonic Boom for a Delta Wing and a Swept Wing-Body Model

    NASA Technical Reports Server (NTRS)

    Castner, Raymond; Lake, Troy

    2012-01-01

    Supersonic travel is not allowed over populated areas due to the disturbance caused by the sonic boom. Research has been performed on sonic boom reduction and has included the contribution of the exhaust nozzle plume. Plume effect on sonic boom has progressed from the study of isolated nozzles to a study with four exhaust plumes integrated with a wing-body vehicle. This report provides a baseline analysis of the generic wing-body vehicle to demonstrate the effect of the nozzle exhaust on the near-field pressure profile. Reductions occurred in the peak-to-peak magnitude of the pressure profile for a swept wing-body vehicle. The exhaust plumes also had a favorable effect as the nozzles were moved outward along the wing-span.

  4. Real Time Diagnostics of Jet Engine Exhaust Plumes Using a Chirped QC Laser Spectrometer

    NASA Astrophysics Data System (ADS)

    Hay, K. G.; Duxbury, G.; Langford, N.

    2010-06-01

    Quantitative measurements of real-time variations of the chemical composition of a jet engine exhaust plume is demonstrated using a 4.86 μmn intra-pulse quantum cascade laser spectrometer. The measurements of the gas turbine exhaust were carried out in collaboration with John Black and Mark Johnson at Rolls Royce. The recording of five sets of averaged spectra a second has allowed us to follow the build up of the combustion products within the exhaust, and to demonstrate the large variation of the integrated absorption of these absorption lines with temperature. The absorption cross sections of the lines of both carbon monoxide and water increase with temperature, whereas those of the three main absorption lines of carbon dioxide decrease. At the steady state limit the absorption lines of carbon dioxide are barely visible, and the spectrum is dominated by absorption lines of carbon monoxide and water.

  5. Wind Tunnel Model Design for the Study of Plume Effects on Sonic Boom for Isolated Exhaust Nozzles

    NASA Technical Reports Server (NTRS)

    Castner, Raynold S.

    2010-01-01

    A low cost test capability was developed at the NASA Glenn Research Center 1- by 1-Foot Supersonic Wind Tunnel (SWT), with a goal to reduce the disturbance caused by supersonic aircraft flight over populated areas. This work focused on the shock wave structure caused by the exhaust nozzle plume. Analysis and design was performed on a new rig to test exhaust nozzle plume effects on sonic boom signature. Test capability included a baseline nozzle test article and a wind tunnel model consisting of a strut, a nosecone and an upper plenum. Analysis was performed on the external and internal aerodynamic configuration, including the shock reflections from the wind tunnel walls caused by the presence of the model nosecone. This wind tunnel model was designed to operate from Mach 1.4 to Mach 3.0 with nozzle pressure ratios from 6 to 12 and altitudes from 30,000 ft (4.36 psia) to 50,000 ft (1.68 psia). The model design was based on a 1 in. outer diameter, was 9 in. in overall length, and was mounted in the wind tunnel on a 3/8 in. wide support strut. For test conditions at 50,000 ft the strut was built to supply 90 psia of pressure, and to achieve 20 psia at the nozzle inlet with a maximum nozzle pressure of 52 psia. Instrumentation was developed to measure nozzle pressure ratio, and an external static pressure probe was designed to survey near field static pressure profiles at one nozzle diameter above the rig centerline. Model layout placed test nozzles between two transparent sidewalls in the 1 1 SWT for Schlieren photography and comparison to CFD analysis.

  6. Wind Tunnel Model Design for the Study of Plume Effects on Sonic Boom for Isolated Exhaust Nozzles

    NASA Technical Reports Server (NTRS)

    Castner, Raymond S.

    2009-01-01

    A low cost test capability was developed at the NASA Glenn Research Center 1- by 1-Foot Supersonic Wind Tunnel (SWT), with a goal to reduce the disturbance caused by supersonic aircraft flight over populated areas. This work focused on the shock wave structure caused by the exhaust nozzle plume. Analysis and design was performed on a new rig to test exhaust nozzle plume effects on sonic boom signature. Test capability included a baseline nozzle test article and a wind tunnel model consisting of a strut, a nose cone and an upper plenum. Analysis was performed on the external and internal aerodynamic configuration, including the shock reflections from the wind tunnel walls caused by the presence of the model nosecone. This wind tunnel model was designed to operate from Mach 1.4 to Mach 3.0 with nozzle pressure ratios from 6 to 12 and altitudes from 30,000 ft (4.36 psia) to 50,000 ft (1.68 psia). The model design was based on a 1 in. outer diameter, was 9 in. in overall length, and was mounted in the wind tunnel on a 3/8 in. wide support strut. For test conditions at 50,000 ft the strut was built to supply 90 psia of pressure, and to achieve 20 psia at the nozzle inlet with a maximum nozzle pressure of 52 psia. Instrumentation was developed to measure nozzle pressure ratio, and an external static pressure probe was designed to survey near field static pressure profiles at one nozzle diameter above the rig centerline. Model layout placed test nozzles between two transparent sidewalls in the 1x1 SWT for Schlieren photography and comparison to CFD analysis.

  7. Issues related to aircraft take-off plumes in a mesoscale photochemical model.

    PubMed

    Bossioli, Elissavet; Tombrou, Maria; Helmis, Costas; Kurtenbach, Ralf; Wiesen, Peter; Schäfer, Klaus; Dandou, Aggeliki; Varotsos, Kostas V

    2013-07-01

    The physical and chemical characteristics of aircraft plumes at the take-off phase are simulated with the mesoscale CAMx model using the individual plume segment approach, in a highly resolved domain, covering the Athens International Airport. Emission indices during take-off measured at the Athens International Airport are incorporated. Model predictions are compared with in situ point and path-averaged observations (NO, NO₂) downwind of the runway at the ground. The influence of modeling process, dispersion properties and background air composition on the chemical evolution of the aircraft plumes is examined. It is proven that the mixing properties mainly determine the plume dispersion. The initial plume properties become significant for the selection of the appropriate vertical resolution. Besides these factors, the background NOx and O₃ concentration levels control NOx distribution and their conversion to nitrogen reservoir species. PMID:23584035

  8. Simulation of UV atomic radiation for application in exhaust plume spectrometry

    NASA Technical Reports Server (NTRS)

    Wallace, T. L.; Powers, W. T.; Cooper, A. E.

    1993-01-01

    Quantitative analysis of exhaust plume spectral data has long been a goal of developers of advanced engine health monitoring systems which incorporate optical measurements of rocket exhaust constituents. Discussed herein is the status of present efforts to model and predict atomic radiation spectra and infer free-atom densities from emission/absorption measurements as part of the Optical Plume Anomaly Detection (OPAD) program at Marshall Space Flight Center (MSFC). A brief examination of the mathematical formalism is provided in the context of predicting radiation from the Mach disk region of the SSME exhaust flow at nominal conditions during ground level testing at MSFC. Computational results are provided for Chromium and Copper at selected transitions which indicate a strong dependence upon broadening parameter values determining the absorption-emission line shape. Representative plots of recent spectral data from the Stennis Space Center (SSC) Diagnostic Test Facility (DTF) rocket engine are presented and compared to numerical results from the present self-absorbing model; a comprehensive quantitative analysis will be reported at a later date.

  9. Simulation of UV atomic radiation for application in exhaust plume spectrometry

    NASA Astrophysics Data System (ADS)

    Wallace, T. L.; Powers, W. T.; Cooper, A. E.

    1993-06-01

    Quantitative analysis of exhaust plume spectral data has long been a goal of developers of advanced engine health monitoring systems which incorporate optical measurements of rocket exhaust constituents. Discussed herein is the status of present efforts to model and predict atomic radiation spectra and infer free-atom densities from emission/absorption measurements as part of the Optical Plume Anomaly Detection (OPAD) program at Marshall Space Flight Center (MSFC). A brief examination of the mathematical formalism is provided in the context of predicting radiation from the Mach disk region of the SSME exhaust flow at nominal conditions during ground level testing at MSFC. Computational results are provided for Chromium and Copper at selected transitions which indicate a strong dependence upon broadening parameter values determining the absorption-emission line shape. Representative plots of recent spectral data from the Stennis Space Center (SSC) Diagnostic Test Facility (DTF) rocket engine are presented and compared to numerical results from the present self-absorbing model; a comprehensive quantitative analysis will be reported at a later date.

  10. Stratospheric plume dispersion: Measurements from STS and Titan solid rocket motor exhaust. Technical report

    SciTech Connect

    Beiting, E.J.

    1999-04-20

    Plume expansion was measured from nine Space Shuttle and Titan IV vehicles at altitudes of 18, 24, and 30 km in the stratosphere. The plume diameters were inferred from electronic images of polarized, near-infrared solar radiation scattered from the exhaust particles, and these diameters were found to increase linearly with time. The expansion rate was measured for as long as 50 min after the vehicle reached altitude. Measurements made simultaneously at multiple altitudes showed that the expansion rate increased with increasing altitude for six measurements made at Cape Canaveral but decreased between 24 and 30 km for the one measurement made at Vandenberg AFB. The average expansion rates for all measurements are 4.3 {+-} 1.0 m/s at 18 km, 6.8 {+-} 1.9 m/s at 24 km, and 8.7 {+-} 2.5 m/s at 30 km. Expansion rates varied from launch to launch by as much as a factor of 1.6 at 18 km, 2.2 at 24 km, and 2.7 at 30 km. No correlation between the expansion rate and wind speed or shear was evident. These data are compared to several models for diffusivity and are used to update a comprehensive particle model of solid rocket motor exhaust in the stratosphere. The expansion rates are required by models to calculate the spatial extent and temporal persistence of the local stratospheric ozone depletion cause by solid rocket exhaust.

  11. Wavelength-Agile Optical Sensor for Exhaust Plume and Cryogenic Fluid Interrogation

    NASA Technical Reports Server (NTRS)

    Sanders, Scott T.; Chiaverini, Martin J.; Gramer, Daniel J.

    2004-01-01

    Two optical sensors developed in UW-Madison labs were evaluated for their potential to characterize rocket engine exhaust plumes and liquid oxygen (LOX) fluid properties. The plume sensor is based on wavelength-agile absorption spectroscopy A device called a chirped white pulse emitter (CWPE) is used to generate the wavelength agile light, scanning, for example, 1340 - 1560 nm every microsecond. Properties of the gases in the rocket plume (for example temperature and water mole fraction) can be monitored using these wavelength scans. We have performed preliminary tests in static gas cells, a laboratory GOX/GH2 thrust chamber, and a solid-fuel hybrid thrust chamber, and these initial tests demonstrate the potential of the CWPE for monitoring rocket plumes. The LOX sensor uses an alternative to wavelength agile sensing: two independent, fixed-wavelength lasers are combined into a single fiber. One laser is absorbed by LOX and the other not: by monitoring the differential transmission the LOX concentration in cryogenic feed lines can be inferred. The sensor was successful in interrogating static LOX pools in laboratory tests. Even in ice- and bubble-laden cryogenic fluids, LOX concentrations were measured to better than 1% with a 3 microsec time constant.

  12. On-board Optical Spectrometry for Detection of Mixture Ratio and Eroded Materials in Rocket Engine Exhaust Plume

    NASA Technical Reports Server (NTRS)

    Barkhoudarian, Sarkis; Kittinger, Scott

    2006-01-01

    Optical spectrometry can provide means to characterize rocket engine exhaust plume impurities due to eroded materials, as well as combustion mixture ratio without any interference with plume. Fiberoptic probes and cables were designed, fabricated and installed on Space Shuttle Main Engines (SSME), allowing monitoring of the plume spectra in real time with a Commercial of the Shelf (COTS) fiberoptic spectrometer, located in a test-stand control room. The probes and the cables survived the harsh engine environments for numerous hot-fire tests. When the plume was seeded with a nickel alloy powder, the spectrometer was able to successfully detect all the metallic and OH radical spectra from 300 to 800 nanometers.

  13. An experimental and computational study of moderately underexpanded rocket exhaust plumes in a co-flowing hypersonic free stream

    SciTech Connect

    Morris, N.; Buttsworth, D.; Jones, T.; Brescianini, C. |

    1995-09-01

    Rocket plume exhaust structures are aerodynamically and thermochemically very complex and the prediction of plume properties such as temperature, velocity, pressure, chemical species concentrations and turbulence properties is a formidable task as there are no definitive models for viscous and chemical effects. Contemporary computational techniques are still in their infancy and cannot yet reliably predict plume properties. Only through validation of computer codes using experimental data, can computational models be developed to the point where they can be confidently used as design and predictive tools. The motivation for this study was to acquire well defined data for rocket plumes at low altitude hypersonic flight conditions so that the above issues could be investigated.

  14. Lidar for remote measurement of ozone in the exhaust plumes of launch vehicles

    NASA Astrophysics Data System (ADS)

    Gelbwachs, Jerry A.

    1996-05-01

    Large quantities of chlorine and alumina particles are injected directly into the stratosphere by the current fleet of launch vehicles. Environmental concerns have been raised over the impact of the rocket exhaust on the ozone layer. Recently, differential absorption lidar (DIAL) was selected for remote sensing of ozone density within the plumes of Titan IV launch vehicles. The application of DIAL to this very challenging problem is described, and an implementation of UV-ozone DIAL is discussed that holds promise for this application.

  15. Exhaust plume and contamination characteristics of a bipropellant (MMH/N2O4) RCS thruster

    NASA Technical Reports Server (NTRS)

    Spisz, E. W.; Bowman, R. L.; Jack, J. R.

    1973-01-01

    Results are presented for three recent tests in a series of thruster contamination experiments made in liquid helium-cooled environmental facility. The contaminating effects encountered on various materials, surfaces, and components, due to the exhaust products from a 5-pound thrust, bipropellant (MMH/N2O4) thruster are investigated. The angular distribution of plume effects around the periphery of the thruster established by transmittance changes of quartz samples over the wavelength range from 0.2 to 2.0 micrometer is studied, along with mass deposition rates at a specific location measured with a quartz crystal microbalance for three different experiments. Quadrupole mass spectrometer measurements of the exhaust products over the mass number range from 12 to 75; infrared transmittance measurements of contaminated samples for the wavelength range from 2.5 to 15 microns; and infrared transmittance measurements of residue from the thruster nozzle are also considered.

  16. Approach to SSME health monitoring. II - Exhaust plume emission spectroscopy at the DTF

    NASA Technical Reports Server (NTRS)

    Tejwani, Gopal D.; Loboda, John A.; Wheatley, Joseph S.; Chenevert, Donald J.

    1990-01-01

    The Diagnostics Testbed Facility (DTF) located at the Stennis Space Center (SSC) is used for obtaining extensive sets of H2O2 exhaust plume emission spectral data for the SSME critical components related elements and materials. The SSME related elements and materials are simulated by mixing appropriate amounts of compounds of their respective constituent elements in an aqueous solution which is injected into the combustion chamber of the DTFT. Five of the most critical components of the SSME which have experienced very severe wear and tear problems in the past are analyzed. These are high pressure turbopump (HPTP) turbine blades, HPTP turbine disks, HPTP bearing, main injector LOX posts, and the main combustion chamber structural shell. The alloys used in the manufacturing of these components are MAR-M 246 + Hf, Waspaloy X, AISI 440C, Haynes 188, and Inconel 718, respectively. The experimental setup and procedures at the DTF are described; stratospheric data for the five alloys are presented; and strategies for the material identification in the SSME exhaust plume are discussed.

  17. Summary of measurement results of ozone, methane, and nonmethane hydrocarbons for C-54 aircraft. 1979 Southeastern Virginia Urban Plume Study

    NASA Technical Reports Server (NTRS)

    Cofer, W. R., III; Purgold, G. C.; Gregory, G. L.

    1981-01-01

    Methane, nonmethane hydrocarbon, and ozone data collected in a C-54 aircraft during the 1979 Southeastern Virginia Urban Plume Study are presented. Three major aircraft experiments were flown on five separate days in August collecting 20 hours of flight data. Direct correlation between ozone and hydrocarbon plumes was observed on several occasions.

  18. Effects of nozzle exit geometry and pressure ratio on plume shape for nozzles exhausting into quiescent air

    NASA Technical Reports Server (NTRS)

    Scallion, William I.

    1991-01-01

    The effects of varying the exit geometry on the plume shapes of supersonic nozzles exhausting into quiescent air at several exit-to-ambient pressure ratios are given. Four nozzles having circular throat sections and circular, elliptical and oval exit cross sections were tested and the exit plume shapes are compared at the same exit-to-ambient pressure ratios. The resulting mass flows were calculated and are also presented.

  19. Three-dimensional reconstruction method on the PDE exhaust plume flow flame temperature field

    NASA Astrophysics Data System (ADS)

    Zhang, Zhimin; Wan, Xiong; Luo, Ningning; Li, Shujing

    2010-10-01

    Pulse detonation engine (referred to as PDE) has many advantage about simple structure, high efficiency thermal [1] cycling etc. In the future, it can be widely used in unmanned aircraft, target drone, luring the plane, the imaginary target, target missiles, long-range missiles and other military targets. However, because the exhaust flame of PDE is complicated [2], non-uniform temperature distribution and mutation in real time, its 3-D temperature distribution is difficult to be measured by normal way. As a result, PDE is used in the military project need to face many difficulties and challenges. In order to analyze and improve the working performance of PDE, deep research on the detonation combustion process is necessary. However, its performance characteristic which is in non-steady-state, as well as high temperature, high pressure, transient combustion characteristics put forward high demands about the flow field parameters measurement. In this paper, the PDE exhaust flames temperature field is reconstructed based on the theory of radiation thermometry [3] and Emission Spectral Tomography (referred to as EST) [4~6] which is one branch of Optical CT. It can monitor the detonation wave temperature distribution out of the exhaust flames at different moments, it also provides authentication for the numerical simulation which directs towards PDE work performance, and then it provides the basis for improving the structure of PDE.

  20. Concepts for reducing exhaust emissions and fuel consumption of the aircraft piston engine

    NASA Technical Reports Server (NTRS)

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

    1979-01-01

    A study was made to reduce exhaust emissions and fuel consumption of a general aviation aircraft piston engine by applying known technology. Fourteen promising concepts such as stratified charge combustion chambers, cooling cylinder head improvements, and ignition system changes were evaluated for emission reduction and cost effectiveness. A combination of three concepts, improved fuel injection system, improved cylinder head with exhaust port liners and exhaust air injection was projected as the most cost effective and safe means of meeting the EPA standards for CO, HC and NO. The fuel economy improvement of 4.6% over a typical single engine aircraft flight profile does not though justify the added cost of the three concepts, and significant reductions in fuel consumption must be applied to the cruise mode where most of the fuel is used. The use of exhaust air injection in combination with exhaust port liners reduces exhaust valve stem temperatures which can result in longer valve guide life. The use of exhaust port liners alone can reduce engine cooling air requirements by 11% which is the equivalent of a 1.5% increase in propulsive power. The EPA standards for CO, HC and NO can be met in the IO-520 engine using air injection alone or the Simmonds improved fuel injection system.

  1. Space shuttle SRM plume expansion sensitivity analysis. [flow characteristics of exhaust gases from solid propellant rocket engines

    NASA Technical Reports Server (NTRS)

    Smith, S. D.; Tevepaugh, J. A.; Penny, M. M.

    1975-01-01

    The exhaust plumes of the space shuttle solid rocket motors can have a significant effect on the base pressure and base drag of the shuttle vehicle. A parametric analysis was conducted to assess the sensitivity of the initial plume expansion angle of analytical solid rocket motor flow fields to various analytical input parameters and operating conditions. The results of the analysis are presented and conclusions reached regarding the sensitivity of the initial plume expansion angle to each parameter investigated. Operating conditions parametrically varied were chamber pressure, nozzle inlet angle, nozzle throat radius of curvature ratio and propellant particle loading. Empirical particle parameters investigated were mean size, local drag coefficient and local heat transfer coefficient. Sensitivity of the initial plume expansion angle to gas thermochemistry model and local drag coefficient model assumptions were determined.

  2. 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.

  3. Laser beam propagation through a full scale aircraft turboprop engine exhaust

    NASA Astrophysics Data System (ADS)

    Henriksson, Markus; Gustafsson, Ove; Sjöqvist, Lars; Seiffer, Dirk; Wendelstein, Norbert

    2010-10-01

    The exhaust from engines introduces zones of extreme turbulence levels in local environments around aircraft. This may disturb the performance of aircraft mounted optical and laser systems. The turbulence distortion will be especially devastating for optical missile warning and laser based DIRCM systems used to protect manoeuvring aircraft against missile attacks, situations where the optical propagation path may come close to the engine exhaust. To study the extent of the turbulence zones caused by the engine exhaust and the strength of the effects on optical propagation through these zones a joint trial between Germany, the Netherlands, Sweden and the United Kingdom was performed using a medium sized military turboprop transport aircraft tethered to the ground at an airfield. This follows on earlier trials performed on a down-scaled jet-engine test rig. Laser beams were propagated along the axis of the aircraft at different distances relative to the engine exhaust and the spatial beam profiles and intensity scintillations were recorded with cameras and photodiodes. A second laser beam path was directed from underneath the loading ramp diagonally past one of the engines. The laser wavelengths used were 1.5 and 3.6 μm. In addition to spatial beam profile distortions temporal effects were investigated. Measurements were performed at different propeller speeds and at different distances from exhaust nozzle to the laser path. Significant increases in laser beam wander and long term beam radius were observed with the engine running. Corresponding increases were also registered in the scintillation index and the temporal fluctuations of the instantaneous power collected by the detector.

  4. Effects of motion on jet exhaust noise from aircraft

    NASA Technical Reports Server (NTRS)

    Chun, K. S.; Berman, C. H.; Cowan, S. J.

    1976-01-01

    The various problems involved in the evaluation of the jet noise field prevailing between an observer on the ground and an aircraft in flight in a typical takeoff or landing approach pattern were studied. Areas examined include: (1) literature survey and preliminary investigation, (2) propagation effects, (3) source alteration effects, and (4) investigation of verification techniques. Sixteen problem areas were identified and studied. Six follow-up programs were recommended for further work. The results and the proposed follow-on programs provide a practical general technique for predicting flyover jet noise for conventional jet nozzles.

  5. Loss rate of NO y from a power plant plume based on aircraft measurements

    NASA Astrophysics Data System (ADS)

    Gillani, N. V.; Luria, M.; Valente, R. J.; Tanner, R. L.; Imhoff, R. E.; Meagher, J. F.

    1998-09-01

    This study was motivated by the recent work of Buhr et al. [1996] which reported losses of NOy from large power plant plumes as high as 0.25 hour-1, much higher than generally accepted values. If true, conclusions pertaining to the efficiency of ozone and nitrate production in the lower troposphere would need major revisions. The results of Buhr et al. were based on aircraft measurements in four TVA (Tennessee Valley Authority) power plant plumes on July 7, 1995, as part of the Nashville/Middle Tennessee Ozone Study, a measurement program of the Southern Oxidants Study (SOS), whereas the results reported in this paper are also based on measurements made in the same SOS study aboard another instrumented aircraft (the TVA helicopter), in plumes of one of these power plants (the Cumberland Steam Plant in northwestern Tennessee) during five different days in 1994 and 1995. Between the 1994 and 1995 sampling periods, emissions of SO2 at the Cumberland plant were reduced by nearly 95% by installation of scrubbers. Our data from the one 1994 day show that the ratio of excess SO2 to NOy, in the plume core increased significantly with plume age, indicating a potentially high differential loss rate of NOy (excess loss of NOy relative to SO2) of about 0.12 hour-1. However, results based on the larger 1995 data set indicate a low differential NOy loss rate of only 0.00±0.03 hour-1, consistent with accepted low loss rates. Because the SOS-Nashville/Middle Tennessee Ozone Study was not specifically designed to explore the NOy loss issue, the question of NOy loss rates in plumes is not currently resolved and additional focused field studies are needed.

  6. Modification of Roberts' Theory for Rocket Exhaust Plumes Eroding Lunar Soil

    NASA Technical Reports Server (NTRS)

    Metzger, Philip T.; Lane, John E.; Immer, Christopher D.

    2008-01-01

    In preparation for the Apollo program, Leonard Roberts developed a remarkable analytical theory that predicts the blowing of lunar soil and dust beneath a rocket exhaust plume. Roberts' assumed that the erosion rate is determined by the "excess shear stress" in the gas (the amount of shear stress greater than what causes grains to roll). The acceleration of particles to their final velocity in the gas consumed a portion of the shear stress. The erosion rate continues to increase until the excess shear stress is exactly consumed, thus determining the erosion rate. He calculated the largest and smallest particles that could be eroded based on forces at the particle scale, but the erosion rate equation assumes that only one particle size exists in the soil. He assumed that particle ejection angles are determined entirely by the shape of the terrain, which acts like a ballistic ramp, the particle aerodynamics being negligible. The predicted erosion rate and particle upper size limit appeared to be within an order of magnitude of small-scale terrestrial experiments, but could not be tested more quantitatively at the time. The lower particle size limit and ejection angle predictions were not tested.

  7. 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

  8. 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

  9. Spectroscopic studies of the exhaust plume of a quasi-steady MPD accelerator. Ph.D. Thesis

    NASA Technical Reports Server (NTRS)

    Bruckner, A. P.

    1972-01-01

    Spectroscopic and photographic investigations are reported that reveal a complex azimuthal species structure in the exhaust plume of a quasi-steady argon MPD accelerator. Over a wide range of operating conditions the injected argon remains collimated in discrete jets which are azimuthally in line with the six propellant injector orifices. The regions between these argon jets, including the central core of the exhaust flow, are occupied by impurities such as carbon, hydrogen and oxygen ablated from the Plexiglas back plate of the arc chamber. The features of this plume structure are found to be dependent on the arc current and mass flow rate. It is found that nearly half the observed velocity is attained in an acceleration region well downstream of the region of significant electromagnetic interaction. Recombination calculations show that the ionization energy is essentially frozen.

  10. 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).

  11. Performance Characteristics of an Aircraft Engine with Exhaust Turbine Supercharger, Special Report

    NASA Technical Reports Server (NTRS)

    Lester, E. M.; Paulson, V. A.

    1941-01-01

    The Pratt and Whitney Aircraft company and the Naval Aircraft Factory of the United States Navy cooperated in a laboratory and flight program of tests on an exhaust turbine supercharger. Two series of dynamometer tests of the engine super-charger combination were completed under simulated altitude conditions. One series of hot gas-chamber tests was conducted by the manufacturer of the supercharger. Flight demonstrations of the supercharger installed in a twin-engine flying boat were terminated by failure of the turbine wheels. The analysis of the results indicated that a two-stage supercharger with the first-stage exhaust turbine driven will deliver rated power for a given indicated power to a higher altitude, will operate more efficiently, and will require simpler controls than a similar engine with the first stage of the supercharger driven from the crankshaft through multispeed gears.

  12. The Kinetic Nonequilibrium Processes in the Internal Flow and in the Plume of Subsonic and Supersonic Aircrafts

    NASA Technical Reports Server (NTRS)

    Starik, Alexander M.

    1997-01-01

    (1) Our results show that under combustion of thermal destruction products of n-C8H18, and other hydrocarbon fuels with air at the equivalent ratio -0.5 and less the chemical equilibrium is not realized at the exit plane of combustion chamber and in the gas turbine and nozzle for most of small components such as NO2, NO3, HNO, HNO2, HNO3, N(x)H(y), HO2, OH. The chemical equilibrium is not realized in the internal flow of ramjet hydrogen combustion engine too. So at the nozzle exit plane both of gas-turbine hydrocarbon combustion engine and of ramjet hydrogen combustion engine the relatively large values of concentration of such small components as NO3, HNO2, N2O, HNO3, HNO, NH, N2H, HO2, H2O2 may be realized. The exact definition of these component concentration as well as concentration of NO(x), OH, SO2, O, H, H2, H2O at the nozzle exit plane is very important for plume chemistry. (2) The results which were obtained for subsonic and hypersonic aircrafts indicate on the considerable change of the composition of the gas mixture along the plume. This change can be caused not only by the mixture of combustion products with the atmosphere air but by proceeding of whole complex of nonequilibrium photochemical reactions. The photodissociation processes begin to influence on the formation of the free atoms and radicals at flight altitude H greater than or equal to 18 km. Neglect of these processes can result in essential (up to 10(exp 4) times) mistakes of values gamma(sub OH), gamma(sub O), gamma(sub H), gamma(sub HSO3) and some products of CFC's disintegration. It was found that penetration of Cl-containing species from the atmosphere into the exhaust flow and its interaction with nitrogen oxides leads to essential increasing of the concentration of Cl, Cl2, ClO2, ClNO3, CH3Cl and sometimes HCl and the decreasing of ClO concentration by comparison with background values. The results of our analysis show that the plume aircraft with both hydrocarbon and hydrogen

  13. Correlative Observations with Space-Borne Direct Doppler Wind Instruments of the Rapid Transport of Shuttle Exhaust Plumes (Invited)

    NASA Astrophysics Data System (ADS)

    Niciejewski, R.; Meier, R. R.; Stevens, M. H.; Skinner, W. R.; Cooper, M.; Marshall, A.; Ortland, D. A.; Wu, Q.

    2010-12-01

    The Upper Atmosphere Research Satellite (UARS) was launched by Space Shuttle STS-48 on 12 September 1991 and included a direct Doppler experiment, the High Resolution Doppler Imager, HRDI. Ten years later, the TIMED Doppler Interferometer, TIDI, joined HRDI in direct neutral wind observations of the mesosphere and lower thermosphere (MLT). The removal of instrumental artifacts from the raw spectra, complicated by the loss of good attitude knowledge for HRDI and unexpected signal contamination for TIDI has matured to a level where excellent agreement exists for common volume measurements between them. The two experiments were able to perform overlapping measurements of tidal and planetary wave fields for three years permitting unprecedented clarity in the description of the cyclical behaviour of the MLT. The exhaust plume left in the wake of the launch of STS-107 (16 January 2003) provided a stringent test between TIDI, HRDI, and independent imagery, the latter of which showed rapid transport across the equator to the Antarctic. Though TIDI and HRDI observed the atmosphere at the plume’s location at different local solar times, all correlative observations supported the hypothesis indicated by once-a-day images of the plume - rapid southern transport over thousands of kilometers. A simple spectral analysis of simultaneous observations of the neutral winds by HRDI and TIDI indicates that a classical two-day wave (longitudinal wavenumber = 3) exists in the southern hemisphere during the ~80-hour transit time coinciding with the transport of the plume exhaust from launch to the Antarctic. A least-squares fit of the wave in the meridional wind indicates maximum amplitude in the MLT of ~80 m/s southwards. Other shuttle launches have also been accompanied by evidence that implies rapid transport of exhaust plumes to Arctic latitudes. This paper will summarize correlative HRDI and/or TIDI wind observations of these events and associated spectral analysis of the

  14. 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.

  15. Characterizing and overcoming spectral artifacts in imaging Fourier-transform spectroscopy of turbulent exhaust plumes

    NASA Astrophysics Data System (ADS)

    Moore, Elizabeth A.; Gross, Kevin C.; Bowen, Spencer J.; Perram, Glen P.; Chamberland, Martin; Farley, Vincent; Gagnon, Jean-Philippe; Lagueux, Philippe; Villemaire, André

    2009-05-01

    The midwave and shortwave infrared regions of the electromagnetic spectrum contain rich information enabling the characterization of hot, rapid events such as explosions, engine plumes, flares and other combustion events. High-speed sensors are required to analyze the content of such rapidly evolving targets. Cameras with high frame rates and non-imaging spectrometers with high data rates are typically used; however the information from these two types of instruments must be later fused to enable characterization of the transient targets. Imaging spectrometers have recently become commercially available for general scientific use, thus enabling simultaneous capture of both spatial and spectral information without co-registration issues. However, their use against rapidly-varying sources has traditionally been considered problematic, for even at moderate spatial and spectral resolutions the time to acquire a single spectrum can be long compared to the timescales associated with combustion events. This paper demonstrates that imaging Fourier-transform spectroscopy (IFTS) can successfully characterize the turbulent combustion exhaust from a turbojet engine. A Telops Hyper-Cam IFTS collected hyperspectral video from a Turbine Technologies SR-30 turbojet engine with a spectral resolution of δν = 1/cm-1 on a 200×64 pixel sub-window at a rate of 0.3 Hz. Scene-change artifacts (SCAs) are present in the spectra; however, the stochastic fluctuations in source intensity translate into high-frequency "noise." Temporal averaging affords a significant reduction of the noise associated with SCAs. Emission from CO and CO2 are clearly recognized in the averaged spectra, and information about their temperature and relative concentrations is evident.

  16. Using Lunar Module Shadows To Scale the Effects of Rocket Exhaust Plumes

    NASA Technical Reports Server (NTRS)

    2008-01-01

    Excavating granular materials beneath a vertical jet of gas involves several physical mechanisms. These occur, for example, beneath the exhaust plume of a rocket landing on the soil of the Moon or Mars. We performed a series of experiments and simulations (Figure 1) to provide a detailed view of the complex gas-soil interactions. Measurements taken from the Apollo lunar landing videos (Figure 2) and from photographs of the resulting terrain helped demonstrate how the interactions extrapolate into the lunar environment. It is important to understand these processes at a fundamental level to support the ongoing design of higher fidelity numerical simulations and larger-scale experiments. These are needed to enable future lunar exploration wherein multiple hardware assets will be placed on the Moon within short distances of one another. The high-velocity spray of soil from the landing spacecraft must be accurately predicted and controlled or it could erode the surfaces of nearby hardware. This analysis indicated that the lunar dust is ejected at an angle of less than 3 degrees above the surface, the results of which can be mitigated by a modest berm of lunar soil. These results assume that future lunar landers will use a single engine. The analysis would need to be adjusted for a multiengine lander. Figure 3 is a detailed schematic of the Lunar Module camera calibration math model. In this chart, formulas relating the known quantities, such as sun angle and Lunar Module dimensions, to the unknown quantities are depicted. The camera angle PSI is determined by measurement of the imaged aspect ratio of a crater, where the crater is assumed to be circular. The final solution is the determination of the camera calibration factor, alpha. Figure 4 is a detailed schematic of the dust angle math model, which again relates known to unknown parameters. The known parameters now include the camera calibration factor and Lunar Module dimensions. The final computation is the ejected

  17. Workshop on Jet Exhaust Noise Reduction for Tactical Aircraft - NASA Perspective

    NASA Technical Reports Server (NTRS)

    Huff, Dennis L.; Henderson, Brenda S.

    2007-01-01

    Jet noise from supersonic, high performance aircraft is a significant problem for takeoff and landing operations near air bases and aircraft carriers. As newer aircraft with higher thrust and performance are introduced, the noise tends to increase due to higher jet exhaust velocities. Jet noise has been a subject of research for over 55 years. Commercial subsonic aircraft benefit from changes to the engine cycle that reduce the exhaust velocities and result in significant noise reduction. Most of the research programs over the past few decades have concentrated on commercial aircraft. Progress has been made by introducing new engines with design features that reduce the noise. NASA has recently started a new program called "Fundamental Aeronautics" where three projects (subsonic fixed wing, subsonic rotary wing, and supersonics) address aircraft noise. For the supersonics project, a primary goal is to understand the underlying physics associated with jet noise so that improved noise prediction tools and noise reduction methods can be developed for a wide range of applications. Highlights from the supersonics project are presented including prediction methods for broadband shock noise, flow measurement methods, and noise reduction methods. Realistic expectations are presented based on past history that indicates significant jet noise reduction cannot be achieved without major changes to the engine cycle. NASA s past experience shows a few EPNdB (effective perceived noise level in decibels) can be achieved using low noise design features such as chevron nozzles. Minimal thrust loss can be expected with these nozzles (< 0.5%) and they may be retrofitted on existing engines. In the long term, it is desirable to use variable cycle engines that can be optimized for lower jet noise during takeoff operations and higher thrust for operational performance. It is also suggested that noise experts be included early in the design process for engine nozzle systems to participate

  18. The 1979 Southeastern Virginia Urban Plume Study. Volume 1: Description of experiments and selected aircraft data

    NASA Technical Reports Server (NTRS)

    Gregory, G. L.; Lee, R. B., III; Mathis, J. J., Jr.

    1981-01-01

    The Southeastern Virginia Urban Plume Study (SEV-UPS) utilizes remote sensors and satellite platforms to monitor the Earth's environment and resources. SEV-UPS focuses on the application of specific remote sensors to the monitoring and study of specific air quality problems. The 1979 SEV-UPS field program was conducted with specific objectives: (1) to provide correlative data to evaluate the Laser Absorption spectrometer ozone remote sensors; (2) to demonstrate the utility of the sensor for the study of urban ozone problems; (3) to provide additional insights into air quality phenomena occuring in Southeastern Virginia; and (4) to compare measurement results of various in situ measurement platforms. The field program included monitoring from 12 surface stations, 4 aircraft, 2 tethered balloons, 2 radiosonde release sites, and numerous surface meteorological observation sites. The aircraft monitored 03, NO, NOX, Bscat, temperature, and dewpoint temperature.

  19. Plume mass flow and optical damage distributions for an MMH/N2O4 RCS thruster. [exhaust plume contamination of spacecraft components

    NASA Technical Reports Server (NTRS)

    Spisz, E. W.; Bowman, R. L.; Jack, J. R.

    1973-01-01

    The data obtained from two recent experiments conducted in a continuing series of experiments at the Lewis Research Center into the contamination characteristics of a 5-pound thrust MMH/N2O4 engine are presented. The primary objectives of these experiments were to establish the angular distribution of condensible exhaust products within the plume and the corresponding optical damage angular distribution of transmitting optical elements attributable to this contaminant. The plume mass flow distribution was measured by five quartz crystal microbalances (QCM's) located at the engine axis evaluation. The fifth QCM was located above the engine and 15 deg behind the nozzle exit plane. The optical damage was determined by ex-situ transmittance measurements for the wavelength range from 0.2 to 0.6 microns on 2.54 cm diameter fused silica discs also located at engine centerline elevation. Both the mass deposition and optical damage angular distributions followed the expected trend of decreasing deposition and damage as the angle between sensor or sample and the nozzle axis increased. A simple plume gas flow equation predicted the deposition distribution reasonably well for angles of up to 55 degrees. The optical damage measurements also indicated significant effects at large angles.

  20. Numerically Modeling the Erosion of Lunar Soil by Rocket Exhaust Plumes

    NASA Technical Reports Server (NTRS)

    2008-01-01

    In preparation for the Apollo program, Leonard Roberts of the NASA Langley Research Center developed a remarkable analytical theory that predicts the blowing of lunar soil and dust beneath a rocket exhaust plume. Roberts assumed that the erosion rate was determined by the excess shear stress in the gas (the amount of shear stress greater than what causes grains to roll). The acceleration of particles to their final velocity in the gas consumes a portion of the shear stress. The erosion rate continues to increase until the excess shear stress is exactly consumed, thus determining the erosion rate. Roberts calculated the largest and smallest particles that could be eroded based on forces at the particle scale, but the erosion rate equation assumed that only one particle size existed in the soil. He assumed that particle ejection angles were determined entirely by the shape of the terrain, which acts like a ballistic ramp, with the particle aerodynamics being negligible. The predicted erosion rate and the upper limit of particle size appeared to be within an order of magnitude of small-scale terrestrial experiments but could not be tested more quantitatively at the time. The lower limit of particle size and the predictions of ejection angle were not tested. We observed in the Apollo landing videos that the ejection angles of particles streaming out from individual craters were time-varying and correlated to the Lunar Module thrust, thus implying that particle aerodynamics dominate. We modified Roberts theory in two ways. First, we used ad hoc the ejection angles measured in the Apollo landing videos, in lieu of developing a more sophisticated method. Second, we integrated Roberts equations over the lunar-particle size distribution and obtained a compact expression that could be implemented in a numerical code. We also added a material damage model that predicts the number and size of divots which the impinging particles will cause in hardware surrounding the landing

  1. The effects of an ion-thruster exhaust plume on S-band carrier transmission

    NASA Technical Reports Server (NTRS)

    Ackerknecht, W. E., III; Stanton, P. H.

    1976-01-01

    The magnitude of the effects of an ion thruster plume on S-band signals is measured. Modeling techniques are developed to predict the effects. Results show that the RF signal transmitted through an ion thruster plume is reduced in amplitude and shifted in phase. An increase in noise is also experienced.

  2. A simulation method of aircraft plumes for real-time imaging

    NASA Astrophysics Data System (ADS)

    Li, Ni; Lv, Zhenhua; Huai, Wenqin; Gong, Guanghong

    2016-07-01

    Real-time infrared simulation technology can provide a large number of infrared images under different conditions to support the design, test and evaluation of a system having infrared imaging equipment with very low costs. By synthesizing heat transfer, infrared physics, fluid mechanics and computer graphics, a real-time infrared simulation method is proposed based on the method of characteristics to predict the infrared feature of aircraft plumes, which tries to obtain a good balance between simulation precision and computation efficiency. The temperature and pressure distribution in the under-expansion status can be rapidly solved with dynamically changing flight statuses and engine working states. And a modified C-G (Curtis-Godson) spectral band model that combines the plume streamlines with the conventional C-G spectral band model was implemented to calculate the non-uniformly distributed radiation parameters inside a plume field. The simulation result was analyzed and compared with the CFD++, which validates the credibility and efficiency of the proposed simulation method.

  3. 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.

  4. Assessment of analytical and experimental techniques utilized in conducting plume technology tests 575 and 593. [exhaust flow simulation (wind tunnel tests) of scale model Space Shuttle Orbiter

    NASA Technical Reports Server (NTRS)

    Baker, L. R.; Sulyma, P. R.; Tevepaugh, J. A.; Penny, M. M.

    1976-01-01

    Since exhaust plumes affect vehicle base environment (pressure and heat loads) and the orbiter vehicle aerodynamic control surface effectiveness, an intensive program involving detailed analytical and experimental investigations of the exhaust plume/vehicle interaction was undertaken as a pertinent part of the overall space shuttle development program. The program, called the Plume Technology program, has as its objective the determination of the criteria for simulating rocket engine (in particular, space shuttle propulsion system) plume-induced aerodynamic effects in a wind tunnel environment. The comprehensive experimental program was conducted using test facilities at NASA's Marshall Space Flight Center and Ames Research Center. A post-test examination of some of the experimental results obtained from NASA-MSFC's 14 x 14-inch trisonic wind tunnel is presented. A description is given of the test facility, simulant gas supply system, nozzle hardware, test procedure and test matrix. Analysis of exhaust plume flow fields and comparison of analytical and experimental exhaust plume data are presented.

  5. Flow field description of the Space Shuttle Vernier reaction control system exhaust plumes

    NASA Technical Reports Server (NTRS)

    Cerimele, Mary P.; Alred, John W.

    1987-01-01

    The flow field for the Vernier Reaction Control System (VRCS) jets of the Space Shuttle Orbiter has been calculated from the nozzle throat to the far-field region. The calculations involved the use of recently improved rocket engine nozzle/plume codes. The flow field is discussed, and a brief overview of the calculation techniques is presented. In addition, a proposed on-orbit plume measurement experiment, designed to improve future estimations of the Vernier flow field, is addressed.

  6. Dispersion of turbojet engine exhaust in flight

    NASA Technical Reports Server (NTRS)

    Holdeman, J. D.

    1973-01-01

    The dispersion of the exhaust of turbojet engines into the atmosphere is estimated by using a model developed for the mixing of a round jet with a parallel flow. The analysis is appropriate for determining the spread and dilution of the jet exhaust from the engine exit until it is entrained in the aircraft trailing vortices. Chemical reactions are not expected to be important and are not included in the flow model. Calculations of the dispersion of the exhaust plumes of three aircraft turbojet engines with and without afterburning at typical flight conditions are presented. Calculated average concentrations for the exhaust plume from a single engine jet fighter are shown to be in good agreement with measurements made in the aircraft wake during flight.

  7. 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.

  8. Using unmanned aircraft to measure the impact of pollution plumes on atmospheric heating rates and cloud properties during the Cheju ABC Plume-Asian Monsoon Experiment (CAPMEX)

    NASA Astrophysics Data System (ADS)

    Venkata Ramana, M.; Ramanathan, V.; Nguyen, H.; Xu, Y.; Pistone, K.; Corrigan, C.; Feng, Y.; Zhu, A.; Kim, S.; Yoon, S.; Carmichael, G. R.; Schauer, J. J.

    2009-12-01

    The CAPMEX (Cheju ABC Plume-Asian Monsoon Experiment) campaign took place off the Coast of Cheju Island in South Korea to take advantage of the unique event associated with the shutdown of anthropogenic emissions surrounding Beijing during the Olympics in summer 2008. CAPMEX studied pollution plumes before, during, and after the Beijing reductions using ground-level and high-elevation measurements, i.e., from unmanned aircrafts. Additionally, the campaign documented the effect on solar heating and clouds due to aerosols carried by the long range transport of pollution plumes. The unmanned aerial vehicle (UAV) measurement component of this campaign took place during Aug 9 to Sept 30, 2008. The AUAV payload was mission-specific and was outfitted to perform a particular set of measurements. These measurements include aerosol concentration, aerosol size distribution, aerosol absorption, cloud drop size distribution, solar radiation fluxes (visible and broadband), and spectral radiative fluxes. Throughout the CAPMEX experiment, long-range transport of aerosols from Beijing, Shanghai and Marine plumes were sampled in aerosol layers up to 3-4 km above sea level. During this period, we captured both heavy and light pollution events and witnessed air masses from both pristine oceanic sources and from major cities including Beijing and Shanghai. Analysis of specific plumes allowed us to quantify the impact of anthropogenic pollution on heating rates and cloud properties.

  9. Comparison of the particle size distribution of heavy-duty diesel exhaust using a dilution tailpipe sampler and an in-plume sampler during on-road operation.

    PubMed

    Brown, J E; Clayton, M J; Harris, D B; King, F G

    2000-08-01

    Originally constructed to develop gaseous emission factors for heavy-duty diesel trucks, the U.S. Environmental Protection Agency's (EPA) On-Road Diesel Emissions Characterization Facility has been modified to incorporate particle measurement instrumentation. An electrical low-pressure impactor designed to continuously measure and record size distribution data was used to monitor the particle size distribution of heavy-duty diesel truck exhaust. For this study, which involved a high-mileage (900,000 mi) truck running at full load, samples were collected by two different methods. One sample was obtained directly from the exhaust stack using an adaptation of the University of Minnesota's air-ejector-based mini-dilution sampler. The second sample was pulled from the plume just above the enclosed trailer, at a point approximately 11 m from the exhaust discharge. Typical dilution ratios of about 300:1 were obtained for both the dilution and plume sampling systems. Hundreds of particle size distributions were obtained at each sampling location. These were compared both selectively and cumulatively to evaluate the performance of the dilution system in simulating real-world exhaust plumes. The data show that, in its current residence-time configuration, the dilution system imposes a statistically significant bias toward smaller particles, with substantially more nanoparticles being collected than from the plume sample. PMID:11002602

  10. Detection of very large ions in aircraft gas turbine engine combustor exhaust: charged small soot particles?

    NASA Astrophysics Data System (ADS)

    Wilhelm, S.; Haverkamp, H.; Sorokin, A.; Arnold, F.

    Small electrically charged soot particles (CSP) present in the exhaust of a jet aircraft engine combustor have been detected by a Large Ion Mass Spectrometer and quantitatively measured by an Ion Mobility Analyzer. The size and concentration measurements which took place at an aircraft gas-turbine engine combustor test-rig at the ground covered different combustor conditions (fuel flow=FF, fuel sulphur content=FSC). At the high-pressure turbine stage of the engine, CSP-diameters were mostly around 6 nm and CSP-concentrations reached up to 4.8×10 7 cm -3 (positive and negative) corresponding to a CSP-emission index ECSP=2.5×10 15 CSP kg -1 fuel burnt. The ECSP increased with FF but did not increase with FSC. The latter indicates that sulphur was not a major component of the large ions. Possible CSP-sources and CSP-sinks as well as CSP-roles are discussed.

  11. Exhaust Nozzles for Propulsion Systems with Emphasis on Supersonic Cruise Aircraft

    NASA Technical Reports Server (NTRS)

    Stitt, Leonard E.

    1990-01-01

    This compendium summarizes the contributions of the NASA-Lewis and its contractors to supersonic exhaust nozzle research from 1963 to 1985. Two major research and technology efforts sponsored this nozzle research work; the U.S. Supersonic Transport (SST) Program and the follow-on Supersonic Cruise Research (SCR) Program. They account for two generations of nozzle technology: the first from 1963 to 1971, and the second from 1971 to 1985. First, the equations used to calculate nozzle thrust are introduced. Then the general types of nozzles are presented, followed by a discussion of those types proposed for supersonic aircraft. Next, the first-generation nozzles designed specifically for the Boeing SST and the second-generation nozzles designed under the SCR program are separately reviewed and then compared. A chapter on throttle-dependent afterbody drag is included, since drag has a major effect on the off-design performance of supersonic nozzles. A chapter on the performance of supersonic dash nozzles follows, since these nozzles have similar design problems, Finally, the nozzle test facilities used at NASA-Lewis during this nozzle research effort are identified and discussed. These facilities include static test stands, a transonic wind tunnel, and a flying testbed aircraft. A concluding section points to the future: a third generation of nozzles designed for a new era of high speed civil transports to produce even greater advances in performance, to meet new noise rules, and to ensure the continuity of over two decades of NASA research.

  12. Approach to SSME health monitoring. III - Exhaust plume emission spectroscopy: Recent results and detailed analysis

    NASA Astrophysics Data System (ADS)

    Tejwani, Gopal D.; van Dyke, David B.; Bircher, Felix E.

    1993-06-01

    Spectral data for two recent A-1 test firings, 901-717 and 901-718, obtained from an Optical Multichannel Analyzer and an Optical Plume Anomaly Detector, are presented. The spectral data encompasses the database of SSME critical components and materials and the spectral database for the SSME related elements and materials. Relatively strong and continuous emissions from Cr and Fe atomic transitions were observed starting at engine start plus 494 s and persisting until the engine shut off at engine start plus 520 s. These emissions are considered to be emanated from the SSME material AISI 440C, which is traced to high pressure turbopump bearings.

  13. Approach to SSME health monitoring. III - Exhaust plume emission spectroscopy: Recent results and detailed analysis

    NASA Technical Reports Server (NTRS)

    Tejwani, Gopal D.; Van Dyke, David B.; Bircher, Felix E.

    1993-01-01

    Spectral data for two recent A-1 test firings, 901-717 and 901-718, obtained from an Optical Multichannel Analyzer and an Optical Plume Anomaly Detector, are presented. The spectral data encompasses the database of SSME critical components and materials and the spectral database for the SSME related elements and materials. Relatively strong and continuous emissions from Cr and Fe atomic transitions were observed starting at engine start plus 494 s and persisting until the engine shut off at engine start plus 520 s. These emissions are considered to be emanated from the SSME material AISI 440C, which is traced to high pressure turbopump bearings.

  14. 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

  15. Characteristics of aerosol particles and trace gases in ship exhaust plumes

    NASA Astrophysics Data System (ADS)

    Drewnick, F.; Diesch, J.; Borrmann, S.

    2011-12-01

    Gaseous and particulate matter from marine vessels gain increasing attention due to their significant contribution to the anthropogenic burden of the atmosphere, implying the change of the atmospheric composition and the impact on local and regional air quality and climate (Eyring et al., 2010). As ship emissions significantly affect air quality of onshore regions, this study deals with various aspects of gas and particulate plumes from marine traffic measured near the Elbe river mouth in northern Germany. In addition to a detailed investigation of the chemical and physical particle properties from different types of commercial marine vessels, we will focus on the chemistry of ship plumes and their changes while undergoing atmospheric processing. Measurements of the ambient aerosol, various trace gases and meteorological parameters using a mobile laboratory (MoLa) were performed on the banks of the Lower Elbe which is passed on average, daily by 30 ocean-going vessels reaching the port of Hamburg, the second largest freight port of Europe. During 5 days of sampling from April 25-30, 2011 170 commercial marine vessels were probed at a distance of about 1.5-2 km with high temporal resolution. Mass concentrations in PM1, PM2.5 and PM10 and number as well as PAH and black carbon (BC) concentrations in PM1 were measured; size distribution instruments covered the size range from 6 nm up to 32 μm. The chemical composition of the non-refractory aerosol in the submicron range was measured by means of an Aerosol Mass Spectrometer (Aerodyne HR-ToF-AMS). Gas phase species analyzers monitored various trace gas concentrations in the air and a weather station provided meteorological parameters. Additionally, a wide spectrum of ship information for each vessel including speed, size, vessel type, fuel type, gross tonnage and engine power was recorded via Automatic Identification System (AIS) broadcasts. Although commercial marine vessels powered by diesel engines consume high

  16. The 1979 Southeastern Virginia Urban Plume Study. Volume 2: Data listings for NASA Cessna aircraft

    NASA Technical Reports Server (NTRS)

    Gregory, G. L.; Lee, R. B., III; Mathis, J. J., Jr.

    1981-01-01

    The data reported are these measured onboard the NASA Langley chartered Cessna aircraft. Data include ozone, nitrogen oxides, light scattering coefficient, temperature, dewpoint, and aircraft altitude.

  17. 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

  18. Subsidence of aircraft engine exhaust in the stratosphere: Implications for calculated ozone depletions

    NASA Technical Reports Server (NTRS)

    Rodriguez, J. M.; Shia, R.-L.; Ko, M. K. W.; Heisey, C. W.; Weistenstein, D. K.; Miake-Lye, R. C.; Kolb, C. E.

    1994-01-01

    The deposition altitude of nitrogen oxides and other exhaust species emitted by stratospheric aircraft is a crucial parameter in determining the impact of these emissions on stratospheric ozone. We have utilized a model for the wake of a High-Speed Civil Transport (HSCT) to estimate the enhancements in water and reductions in ozone in these wakes as a function of time. Radiative calculations indicate differential cooling rates as large as -5K/day at the beginning of the far-wake regime, mostly due to the enhanced water abundance. These cooling rates would imply a net sinking of the wakes of about 1.2 km after three days in the limit of no mixing. Calculated mid-latitude column ozone reductions due to emissions from a Mach 2.4 HSCT would then change from about -1% to -06%. However, more realistic calculations adopting moderate mixing for the wake reduce the net sinking to less than 0.2 km, making the impact of radiative subsidence negligible.

  19. Subsidence of aircraft engine exhaust in the stratosphere: Implications for calculated ozone depletions

    SciTech Connect

    Rodriguez, J.M.; Shia, R.L.; Ko, M.K.W.; Heisey, C.W.; Weistenstein, D.K. ); Miake-Lye, R.C.; Kolb, C.E. )

    1994-01-01

    The deposition altitude of nitrogen oxides and other exhaust species emitted by stratospheric aircraft is a crucial parameter in determining the impact of these emissions on stratospheric ozone. The authors have utilized a model for the wake of a High-Speed Civil Transport (HSCT) to estimate the enhancements in water and reductions in ozone in these wakes as a function of time. Radiative calculations indicate differential cooling rates as large as -5K/day at the beginning of the far-wake regime, mostly due to the enhanced water abundance. These cooling rates would imply a net sinking of the wakes of about 1.2 km after three days in the limit of no mixing. Calculated mid-latitude column ozone reductions due to emissions from a Mach 2.4 HSCT would then change from about-1% to -0.6%. However, more realistic calculations adopting moderate mixing for the wake reduce the net sinking to less than 0.2 km, making the impact of radiative subsidence negligible. 15 refs., 3 figs., 1 tab.

  20. Subsidence of aircraft engine exhaust in the stratosphere: Implications for calculated ozone depletions

    NASA Astrophysics Data System (ADS)

    Rodríguez, J. M.; Shia, R.-L.; Ko, M. K. W.; Heisey, C. W.; Weistenstein, D. K.; Miake-Lye, R. C.; Kolb, C. E.

    1994-01-01

    The deposition altitude of nitrogen oxides and other exhaust species emitted by stratospheric aircraft is a crucial parameter in determining the impact of these emissions on stratospheric ozone. We have utilized a model for the wake of a High-Speed Civil Transport (HSCT) to estimate the enhancements in water and reductions in ozone in these wakes as a function of time. Radiative calculations indicate differential cooling rates as large as -5K/day at the beginning of the far-wake regime, mostly due to the enhanced water abundance. These cooling rates would imply a net sinking of the wakes of about 1.2 km after three days in the limit of no mixing. Calculated mid-latitude column ozone reductions due to emissions from a Mach 2.4 HSCT would then change from about -1% to -0.6%. However, more realistic calculations adopting moderate mixing for the wake reduce the net sinking to less than 0.2 km, making the impact of radiative subsidence negligible.

  1. A Transonic and Surpersonic Investigation of Jet Exhaust Plume Effects on the Afterbody and Base Pressures of a Body of Revolution

    NASA Technical Reports Server (NTRS)

    Andrews, C. D.; Cooper, C. E., Jr.

    1974-01-01

    An experimental aerodynamic investigation was conducted to provide data for studies to determine the criteria for simulating rocket engine plume induced aerodynamic effects in the wind tunnel using a simulated gaseous plume. Model surface and base pressure data were obtained in the presence of both a simulated and a prototype gaseous plume for a matrix of plume properties to enable investigators to determine the parameters that correlate the simulated and prototype plume-induced data. The test program was conducted in the Marshall Space Flight Center's 14 x 14-inch trisonic wind tunnel using two models, the first being a strut mounted cone-ogive-cylinder model with a fineness ratio of 9. Model exterior pressures, model plenum chamber and nozzle performance data were obtained at Mach numbers of 0.9, 1.2, 1.46, and 3.48. The exhaust plume was generated by using air as the simulant gas, or Freon-14 (CF4) as the prototype gas, over a chamber pressure range from 0 to 2,000 psia and a total temperature range from 50 to 600 F.

  2. Hygroscopic Properties of Aircraft Engine Exhaust Aerosol Produced From Traditional and Alternative Fuels

    NASA Astrophysics Data System (ADS)

    Moore, R.; Ziemba, L. D.; Beyersdorf, A. J.; Thornhill, K. L.; Winstead, E. L.; Crumeyrolle, S.; Chen, G.; Anderson, B. E.

    2012-12-01

    Aircraft emissions of greenhouse gases and aerosols constitute an important component of anthropogenic climate forcing, of which aerosol-cloud interactions remain poorly understood. It is currently thought that the ability of these aerosols to alter upper tropospheric cirrus cloud properties may produce radiative forcings many times larger than the impact of linear contrails alone and which may partially offset the impact of greenhouse gas emissions from aviation (Burkhardt and Karcher, Nature, 2011). Consequently, it is important to characterize the ability of these engine-emitted aerosol to act as cloud condensation nuclei (CCN) and ice nuclei (IN) to form clouds. While a number of studies in the literature have examined aerosol-cloud interactions for laboratory-generated soot or from aircraft engines burning traditional fuels, limited attention has been given to how switching to alternative jet fuels impacts the ability of engine-emitted aerosols to form clouds. The key to understanding these changes is the aerosol hygroscopicity. To address this need, the second NASA Alternative Aviation Fuel Experiment (AAFEX-II) was conducted in 2011 to examine the aerosol emissions from the NASA DC-8 under a variety of different engine power and fuel type conditions. Five fuel types were considered including traditional JP-8 fuel, synthetic Fischer-Tropsh (FT) fuel , sulfur-doped FT fuel (FTS) , hydrotreated renewable jet (HRJ) fuel, and a 50:50 blend of JP-8 with HRJ. Emissions were sampled from the DC-8 on the airport jetway at a distance of 145 meters downwind of the engine by a comprehensive suite of aerosol instrumentation that provided information on the aerosol concentration, size distribution, soot mass, and CCN activity. Concurrent measurements of carbon dioxide were used to account for plume dilution so that characteristic emissions indices could be determined. It is found that both engine power and fuel type significantly influence the hygroscopic properties of

  3. Laser Transmission Measurements of Soot Extinction Coefficients in the Exhaust Plume of the X-34 60k-lb Thrust Fastrac Rocket Engine

    NASA Technical Reports Server (NTRS)

    Dobson, C. C.; Eskridge, R. H.; Lee, M. H.

    2000-01-01

    A four-channel laser transmissometer has been used to probe the soot content of the exhaust plume of the X-34 60k-lb thrust Fastrac rocket engine at NASA's Marshall Space Flight Center. The transmission measurements were made at an axial location about equal 1.65 nozzle diameters from the exit plane and are interpreted in terms of homogeneous radial zones to yield extinction coefficients from 0.5-8.4 per meter. The corresponding soot mass density, spatially averaged over the plume cross section, is, for Rayleigh particles, approximately equal to 0.7 micrograms/cubic cm and alternative particle distributions are briefly considered. Absolute plume radiance at the laser wavelength (515 nm) is estimated from the data at approximately equal to 2.200 K equivalent blackbody temperature, and temporal correlations in emission from several spatial locations are noted.

  4. Laser Transmission Measurements of Soot Extinction Coefficients in the Exhaust Plume of the X-34 60K-lb Thrust Fastrac Rocket Engine

    NASA Technical Reports Server (NTRS)

    Dobson, C. C.; Eskridge, R. H.; Lee, M. H.

    2000-01-01

    A four-channel laser transmissometer has been used to probe the soot content of the exhaust plume of the X-34 60k-lb thrust Fastrac rocket engine at NASA's Marshall Space Flight Center. The transmission measurements were made at an axial location approximately equal 1.65 nozzle diameters from the exit plane and are interpreted in terms of homogeneous radial zones to yield extinction coefficients from 0.5-8.4 per meter. The corresponding soot mass density, spatially averaged over the plume cross section, is, for Rayleigh particles, approximately equal 0.7 microgram/cc, and alternative particle distributions are briefly considered. Absolute plume radiance at the laser wavelength (515 nm) is estimated from the data at approximately equal 2,200 K equivalent blackbody temperature, and temporal correlations in emission from several spatial locations are noted.

  5. Summary of 1978 Southeastern Virginia Urban Plume study: Aircraft results for carbon monoxide, methane, nonmethane hydrocarbons, and ozone

    NASA Technical Reports Server (NTRS)

    Hill, G. F.; Sachse, G. W.; Cofer, W. R., III

    1981-01-01

    The characteristics of the Southeastern Virginia urban plume were defined with emphasis on the photon-oxidant species. The measurement area was a rectangle, approximately 150 km by 100 km centered around Cape Charles, Virginia. Included in this area are the cities of Norfolk, Virginia Beach, Chesapeake, Newport News, and Hampton. The area is bounded on the north by Wallops Island, Virginia, and on the south by the Hampton Roads area of Tidewater Virginia. The major axis of the rectangle is oriented in the southwest-northeast direction. The data set includes aircraft measurements for carbon monoxide, methane, nonmethane hydrocarbons, and ozone. The experiment shows that CO can be successfully measured as a tracer gas and used as an index for determining localized and urban plumes. The 1978 data base provided sufficient data to assess an automated chromatograph with flame ionization detection used for measuring methane and nonmethane hydrocarbons in flight.

  6. Simulation investigation of the effect of the NASA Ames 80-by 120-foot wind tunnel exhaust flow on light aircraft operating in the Moffett field trafffic pattern

    NASA Technical Reports Server (NTRS)

    Streeter, Barry G.

    1986-01-01

    A preliminary study of the exhaust flow from the Ames Research Center 80 by 120 Foot Wind Tunnel indicated that the flow might pose a hazard to low-flying light aircraft operating in the Moffett Field traffic pattern. A more extensive evaluation of the potential hazard was undertaken using a fixed-base, piloted simulation of a light, twin-engine, general-aviation aircraft. The simulated aircraft was flown through a model of the wind tunnel exhaust by pilots of varying experience levels to develop a data base of aircraft and pilot reactions. It is shown that a light aircraft would be subjected to a severe disturbance which, depending upon entry condition and pilot reaction, could result in a low-altitude stall or cause damage to the aircraft tail structure.

  7. The use of SE-WORKBENCH for aircraft infrared signature, taken into account body, engine, and plume contributions

    NASA Astrophysics Data System (ADS)

    Cathala, Thierry; Douchin, Nicolas; Joly, André; Perzon, Sven

    2010-04-01

    The aim of this paper is to explain how the combination of CFD++, CFD computational code, RadTherm-IR, 3D thermal computational code and SE-Workbench-EO from OKTAL-SE is an adequate solution for computing the IR signature of a jet aircraft taking all this major into account. An F16 fighter jet cruising at Ma=0.8 has been simulated in CFD++ including a multi species gas with the plume included in the CFD simulation. The solution adopted for computing the radiative transfer through the plume is based on the IRMA module of the NIRATAM software package. A revisited and extended version of IRMA has been integrated in the non real time rendering module of the SE Workbench-EO, SE-RAY-IR The paper illustrates the use of SE-RAY-IR for computing the IR signature of the F16, including the plume, either as an isolated target in the sky or with the background behind.

  8. Comparison of the chemical evolution and characteristics of 495 biomass burning plumes intercepted by the NASA DC-8 aircraft during the ARCTAS/CARB-2008 field campaign

    NASA Astrophysics Data System (ADS)

    Hecobian, A.; Liu, Z.; Hennigan, C. J.; Huey, L. G.; Jimenez, J. L.; Cubison, M. J.; Vay, S.; Diskin, G. S.; Sachse, G. W.; Wisthaler, A.; Mikoviny, T.; Weinheimer, A. J.; Liao, J.; Knapp, D. J.; Wennberg, P. O.; Kürten, A.; Crounse, J. D.; St. Clair, J.; Wang, Y.; Weber, R. J.

    2011-06-01

    This paper compares measurements of gaseous and particulate emissions from a wide range of biomass-burning plumes intercepted by the NASA DC-8 research aircraft during the three phases of the ARCTAS-2008 experiment: ARCTAS-A, based out of Fairbanks, Alaska USA (3 April to 19 April 2008); ARCTAS-B based out of Cold Lake, Alberta, Canada (29 June to 13 July 2008); and ARCTAS-CARB, based out of Palmdale, California, USA (18 June to 24 June 2008). Extensive investigations of boreal fire plume evolution were undertaken during ARCTAS-B, where four distinct fire plumes that were intercepted by the aircraft over a range of down-wind distances (0.1 to 16 hr transport times) were studied in detail. Based on these analyses, there was no evidence for ozone production and a box model simulation of the data confirmed that net ozone production was slow (on average 1 ppbv h-1 in the first 3 h and much lower afterwards) due to limited NOx. Peroxyacetyl nitrate concentrations (PAN) increased with plume age and the box model estimated an average production rate of ~80 pptv h-1 in the first 3 h. Like ozone, there was also no evidence for net secondary inorganic or organic aerosol formation. There was no apparent increase in aerosol mass concentrations in the boreal fire plumes due to secondary organic aerosol (SOA) formation; however, there were indications of chemical processing of the organic aerosols. In addition to the detailed studies of boreal fire plume evolution, about 500 smoke plumes intercepted by the NASA DC-8 aircraft were segregated by fire source region. The normalized excess mixing ratios (i.e. ΔX/ΔCO) of gaseous (carbon dioxide, acetonitrile, hydrogen cyanide, toluene, benzene, methane, oxides of nitrogen (NOx), ozone, PAN) and fine aerosol particulate components (nitrate, sulfate, ammonium, chloride, organic aerosols and water soluble organic carbon) of these plumes were compared.

  9. Plume and wake dynamics, mixing, and chemistry behind an HSCT aircraft

    NASA Technical Reports Server (NTRS)

    Miake-Lye, R. C.; Martinez-Sanchez, M.; Brown, R. C.; Kolb, C. E.

    1991-01-01

    The chemical evolution and mixing and vortical motion of a High Speed Civil Transport's engine exhausts must be analyzed in order to track the gas and its speciation as emissions are mixed to atmospheric scales. Attention is presently given to an analytic model of the wake dynamical processes which accounts for the roll-up of the trailing vorticity, its breakup due to the Crow instability, and the subsequent evolution and motion of the reconnected vorticity. The concentrated vorticity is noted to wrap up the buoyant exhaust and suppress its continued mixing and dilution. The species tracked encompass those which could be heterogeneously reactive on the surfaces of the condensed ice particles, and those capable of reacting with exhaust soot particle surfaces to form active contrail and/or cloud condensation nuclei.

  10. 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.

  11. Three dimensional model calculations of the global dispersion of high speed aircraft exhaust and implications for stratospheric ozone loss

    NASA Technical Reports Server (NTRS)

    Douglass, Anne R.; Rood, Richard B.; Jackman, Charles H.; Weaver, Clark J.

    1994-01-01

    Two-dimensional (zonally averaged) photochemical models are commonly used for calculations of ozone changes due to various perturbations. These include calculating the ozone change expected as a result of change in the lower stratospheric composition due to the exhaust of a fleet of supersonic aircraft flying in the lower stratosphere. However, zonal asymmetries are anticipated to be important to this sort of calculation. The aircraft are expected to be restricted from flying over land at supersonic speed due to sonic booms, thus the pollutant source will not be zonally symmetric. There is loss of pollutant through stratosphere/troposphere exchange, but these processes are spatially and temporally inhomogeneous. Asymmetry in the pollutant distribution contributes to the uncertainty in the ozone changes calculated with two dimensional models. Pollutant distributions for integrations of at least 1 year of continuous pollutant emissions along flight corridors are calculated using a three dimensional chemistry and transport model. These distributions indicate the importance of asymmetry in the pollutant distributions to evaluation of the impact of stratospheric aircraft on ozone. The implications of such pollutant asymmetries to assessment calculations are discussed, considering both homogeneous and heterogeneous reactions.

  12. Validation of scramjet exhaust simulation technique

    NASA Technical Reports Server (NTRS)

    Hopkins, H. B.; Konopka, W.; Leng, J.

    1976-01-01

    Scramjet/airframe integration design philosophy for hypersonic aircraft results in configurations having lower aft surfaces that serve as exhaust nozzles. There is a strong coupling between the exhaust plume and the aerodynamics of the vehicle, making accurate simulation of the engine exhaust mandatory. The experimental verification of the simulation procedure is described. The detonation tube simulator was used to produce an exact simulation of the scramjet exhaust for a Mach 8 flight condition. The pressure distributions produced by the exact exhaust flow were then duplicated by a cool mixture Argon and Freon 13B1. Such a substitute gas mixture validated by the detonation tube technique could be used in conventional wind tunnel tests. The results presented show the substitute gas simulation technique to be valid for shockless expansions.

  13. Falcon 20-E5 Aircraft Flies Close Behind NASA DC-8 to Sample Exhaust

    NASA Video Gallery

    This video was taken from a NASA HU-25C Guardian chase plane looking toward NASA's DC-8, with a Falcon 20-E5 from the German Aerospace Agency (DLR) soon to fly into the DC-8's exhaust. The Falcon i...

  14. Real-Time Analysis of Raman Spectra for Temperature Field Characterization in Aircraft Exhaust Noise Studies

    NASA Astrophysics Data System (ADS)

    Wormhoudt, J.; Nelson, D. D.; Annen, K.; Locke, R. J.; Wernet, M.

    2009-06-01

    Raman scattering has long been used as a non-intrusive diagnostic of temperatures in combustion exhaust flows, using a variety of spectral analysis techniques. As part of their ongoing program of experiments to support development of computer codes that calculate exhaust flow fields and predict jet noise, NASA Glenn Research Center is developing a laser Raman diagnostic system that will measure mean temperatures and temperature fluctuations in hot and cold jet flows. We describe a software package, ART (Analysis for Raman Temperatures), that analyzes Raman spectra of air for temperature and density using vibrational or resolved or unresolved rotational bands, presenting results in a variety of real-time displays. Each analysis technique presents its own challenges in obtaining the most precise and accurate values, and we will comment on these issues by exhibiting example spectra of each type. The ART program is closely related to another Aerodyne software package (TDLWintel) which automates the acquisition and analysis of tunable laser absorption spectra.

  15. Comparison of chemical characteristics of 495 biomass burning plumes intercepted by the NASA DC-8 aircraft during the ARCTAS/CARB-2008 field campaign

    NASA Astrophysics Data System (ADS)

    Hecobian, A.; Liu, Z.; Hennigan, C. J.; Huey, L. G.; Jimenez, J. L.; Cubison, M. J.; Vay, S.; Diskin, G. S.; Sachse, G. W.; Wisthaler, A.; Mikoviny, T.; Weinheimer, A. J.; Liao, J.; Knapp, D. J.; Wennberg, P. O.; Kürten, A.; Crounse, J. D.; St. Clair, J.; Wang, Y.; Weber, R. J.

    2011-12-01

    This paper compares measurements of gaseous and particulate emissions from a wide range of biomass-burning plumes intercepted by the NASA DC-8 research aircraft during the three phases of the ARCTAS-2008 experiment: ARCTAS-A, based out of Fairbanks, Alaska, USA (3 April to 19 April 2008); ARCTAS-B based out of Cold Lake, Alberta, Canada (29 June to 13 July 2008); and ARCTAS-CARB, based out of Palmdale, California, USA (18 June to 24 June 2008). Approximately 500 smoke plumes from biomass burning emissions that varied in age from minutes to days were segregated by fire source region and urban emission influences. The normalized excess mixing ratios (NEMR) of gaseous (carbon dioxide, acetonitrile, hydrogen cyanide, toluene, benzene, methane, oxides of nitrogen and ozone) and fine aerosol particulate components (nitrate, sulfate, ammonium, chloride, organic aerosols and water soluble organic carbon) of these plumes were compared. A detailed statistical analysis of the different plume categories for different gaseous and aerosol species is presented in this paper. The comparison of NEMR values showed that CH4 concentrations were higher in air-masses that were influenced by urban emissions. Fresh biomass burning plumes mixed with urban emissions showed a higher degree of oxidative processing in comparison with fresh biomass burning only plumes. This was evident in higher concentrations of inorganic aerosol components such as sulfate, nitrate and ammonium, but not reflected in the organic components. Lower NOx NEMRs combined with high sulfate, nitrate and ammonium NEMRs in aerosols of plumes subject to long-range transport, when comparing all plume categories, provided evidence of advanced processing of these plumes.

  16. Integrated exhaust gas analysis system for aircraft turbine engine component testing

    NASA Technical Reports Server (NTRS)

    Summers, R. L.; Anderson, R. C.

    1985-01-01

    An integrated exhaust gas analysis system was designed and installed in the hot-section facility at the Lewis Research Center. The system is designed to operate either manually or automatically and also to be operated from a remote station. The system measures oxygen, water vapor, total hydrocarbons, carbon monoxide, carbon dioxide, and oxides of nitrogen. Two microprocessors control the system and the analyzers, collect data and process them into engineering units, and present the data to the facility computers and the system operator. Within the design of this system there are innovative concepts and procedures that are of general interest and application to other gas analysis tasks.

  17. A study of Asian dust plumes using satellite, surface, and aircraft measurements during the INTEX-B field experiment

    NASA Astrophysics Data System (ADS)

    Logan, Timothy; Xi, Baike; Dong, Xiquan; Obrecht, Rebecca; Li, Zhanqing; Cribb, Maureen

    2010-04-01

    Asian dust events occur frequently during the boreal spring season. Their optical properties have been analyzed by using a combination of source region (ground-based and satellite) and remote Pacific Ocean (aircraft) measurements during the Intercontinental Chemical Transport Experiment-Phase B (INTEX-B) field campaign which lasted from 7 April to 15 May 2006. A strong dust event originating from the Gobi Desert and passing over the Xianghe surface site on 17 April 2006 has been extensively analyzed. The surface averaged aerosol optical depth (AOD) values increased from 0.17 (clear sky) to 4.0 (strong dust), and the Angström exponent (α) dropped from 1.26 (clear sky) to below 0.1. Its total downwelling SW flux over the Xianghe site (thousands of kilometers away from the dust source region) is only 46% of the clear-sky value with almost no direct transmission and nearly double the diffuse SW clear-sky value. This event was also captured 6 days later by satellite observations as well as the UND/NASA DC-8 aircraft over the eastern Pacific Ocean. The DC-8 measurements in the remote Pacific region further classified the plumes into dust dominant, pollution dominant, and a mixture of dust and pollution events. HYSPLIT backward trajectories not only verified the origins of each case we selected but also showed (1) two possible origins for the dust: the Gobi and Taklimakan deserts; and (2) pollution: urban areas in eastern China, Japan, and other industrialized cities east of the two deserts. Based on the averaged satellite retrieved AOD data (0.5° × 0.5° grid box), declining AOD values with respect to longitude demonstrated the evolution of the transpacific transport pathway of Asian dust and pollution over the period of the field campaign.

  18. Plume radiation

    NASA Astrophysics Data System (ADS)

    Dirscherl, R.

    1993-06-01

    The electromagnetic radiation originating from the exhaust plume of tactical missile motors is of outstanding importance for military system designers. Both missile- and countermeasure engineer rely on the knowledge of plume radiation properties, be it for guidance/interference control or for passive detection of adversary missiles. To allow access to plume radiation properties, they are characterized with respect to the radiation producing mechanisms like afterburning, its chemical constituents, and reactions as well as particle radiation. A classification of plume spectral emissivity regions is given due to the constraints imposed by available sensor technology and atmospheric propagation windows. Additionally assessment methods are presented that allow a common and general grouping of rocket motor properties into various categories. These methods describe state of the art experimental evaluation techniques as well as calculation codes that are most commonly used by developers of NATO countries. Dominant aspects influencing plume radiation are discussed and a standardized test technique is proposed for the assessment of plume radiation properties that include prediction procedures. These recommendations on terminology and assessment methods should be common to all employers of plume radiation. Special emphasis is put on the omnipresent need for self-protection by the passive detection of plume radiation in the ultraviolet (UV) and infrared (IR) spectral band.

  19. COMPARISON OF THE PARTICLE SIZE DISTRIBUTION OF HEAVY-DUTY DIESEL EXHAUST USING A DILUTION TAIL-PIPE SAMPLER AND IN-PLUME SAMPLER DURING ON-ROAD OPERATION

    EPA Science Inventory

    The paper compares the particle size distribution of heavy-duty diesel exhaust using a dilution tail-pipe sampler and an in-plume sampler during on-road operation. EPA's On-road Diesel Emissions Characterization Facility, modified to incorporate particle measurement instrumentat...

  20. A reexamination of the formation of exhaust condensation trails by jet aircraft

    SciTech Connect

    Hanson, H.M.; Hanson, D.M.

    1995-11-01

    With the end of World War II, it became apparent that a study should be undertaken to identify the factors controlling the production of aircraft condensation trails (contrails). This early work provided a theoretical prediction of T{sub c}, the critical temperature at which the values of the relative humidity and pressure are such that the formation of the contrail phenomenon will occur. As empirical data were obtained, the general agreement at increased altitude was not precise and several studies were made to obtain both theoretical and empirical fits that would provide a {open_quotes}yes/no{close_quotes} decision. These modifications did allow a better decision for the formation of contrails but were found to be increasingly inaccurate at greater altitudes. This study provides an improved algorithm that yields a theoretical prediction that is in general agreement with the available empirical data at all altitudes. It demonstrates that there is a need for additional effort in the identification and precision of relative humidity and pressure that are input to this computation. 7 refs., 3 figs.

  1. Experimental clean combustor program, phase 1. [aircraft exhaust/gas analysis - gas turbine engines

    NASA Technical Reports Server (NTRS)

    Roberts, R.; Peduzzi, A.; Vitti, G. E.

    1975-01-01

    A program of screening three low emission combustors for conventional takeoff and landing, by testing and analyzing thirty-two configurations is presented. Configurations were tested that met the emission goals at idle operating conditions for carbon monoxide and for unburned hydrocarbons (emission index values of 20 and 4, respectively). Configurations were also tested that met a smoke number goal of 15 at sea-level take-off conditions. None of the configurations met the goal for oxides of nitrogen emissions at sea-level take-off conditions. The best configurations demonstrated oxide of nitrogen emission levels that were approximately 61 percent lower than those produced by the JT9D-7 engine, but these levels were still approximately 24 percent above the goal of an emission index level of 10. Additional combustor performance characteristics, including lean blowout, exit temperature pattern factor and radial profile, pressure loss, altitude stability, and altitude relight characteristics were documented. The results indicate the need for significant improvement in the altitude stability and relight characteristics. In addition to the basic program for current aircraft engine combustors, seventeen combustor configurations were evaluated for advanced supersonic technology applications. The configurations were tested at cruise conditions, and a conceptual design was evolved.

  2. 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

  3. Experimental and analytical studies of flow through a ventral and axial exhaust nozzle system for STOVL aircraft

    NASA Technical Reports Server (NTRS)

    Esker, Barbara S.; Debonis, James R.

    1991-01-01

    Flow through a combined ventral and axial exhaust nozzle system was studied experimentally and analytically. The work is part of an ongoing propulsion technology effort at NASA Lewis Research Center for short takeoff, vertical landing (STOVL) aircraft. The experimental investigation was done on the NASA Lewis Powered Lift Facility. The experiment consisted of performance testing over a range of tailpipe pressure ratios from 1 to 3.2 and flow visualization. The analytical investigation consisted of modeling the same configuration and solving for the flow using the PARC3D computational fluid dynamics program. The comparison of experimental and analytical results was very good. The ventral nozzle performance coefficients obtained from both the experimental and analytical studies agreed within 1.2 percent. The net horizontal thrust of the nozzle system contained a significant reverse thrust component created by the flow overturning in the ventral duct. This component resulted in a low net horizontal thrust coefficient. The experimental and analytical studies showed very good agreement in the internal flow patterns.

  4. Aircraft measurements of the impacts of urban plume on cloud activation properties during GoAmazon - preliminary results

    NASA Astrophysics Data System (ADS)

    Mei, F.; Comstock, J. M.; Wang, J.; Tomlinson, J. M.; Hubbe, J. M.; Schmid, B.; Martin, S. T.; Longo, K.; Kuang, C.; Chand, D.; Pekour, M. S.; Shilling, J. E.

    2014-12-01

    Currently, the indirect effects of atmospheric aerosols remain the most uncertain components in forcing of climate change over the industrial period (IPCC, 2007). This large uncertainty is partially a result of our incomplete understanding of the ability of particles to form cloud droplets under atmospherically relevant supersaturations. One of the objectives of the US Department of Energy (DOE) Green Ocean Amazon Project (GoAmazon) is to understand the influence of the emission from Manaus, a tropical megacity, on aerosol size, concentration, and chemical composition, and their impact on aerosol cloud condensation nuclei (CCN) spectrum. During the GoAmazon study, size distributions, CCN spectra and chemical composition of aerosols both under pristine conditions and inside Manaus plume were measured in-situ from the DOE Gulfstream 1 (G-1) research aircraft during two Intensive Operations Periods, one conducted in the wet season (Feb 22- March 24, 2014) and the other in dry season (Sep 1 - Oct 10, 2014). Aerosol size distributions were measured by a Fast Integrated Mobility Spectrometer (FIMS) and compared with the merged size distribution from two other instruments, an Ultra High Sensitivity Aerosol Spectrometer - Airborne (UHSAS-A, DMT), and a Passive Cavity Aerosol Spectrometer Probe (PCASP-200, DMT). Optical measurements of light scattering by nephelometer and absorption by a particle soot absorption photometer (PSAP) were combined with number/size distributions data in a iterative method, which retrieves the effective imaginary refractive index of the particles at a wavelength of 545 nm. Aerosol chemical composition was characterized using a high-resolution time-of-flight aerosol mass spectrometer (HR-ToF-AMS, Aerodyne Inc.). CCN number concentration was measured by a DMT dual column CCN counter at two supersaturations 0.25% and 0.5%. Based on the aerosol properties mentioned above, CCN closure is carried out. In addition, the sensitivity of calculated CCN

  5. 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.

  6. Static test-stand performance of the YF-102 turbofan engine with several exhaust configurations for the Quiet Short-Haul Research Aircraft (QSRA)

    NASA Technical Reports Server (NTRS)

    Mcardle, J. G.; Homyak, L.; Moore, A. S.

    1979-01-01

    The performance of a YF-102 turbofan engine was measured in an outdoor test stand with a bellmouth inlet and seven exhaust-system configurations. The configurations consisted of three separate-flow systems of various fan and core nozzle sizes and four confluent-flow systems of various nozzle sizes and shapes. A computer program provided good estimates of the engine performance and of thrust at maximum rating for each exhaust configuration. The internal performance of two different-shaped core nozzles for confluent-flow configurations was determined to be satisfactory. Pressure and temperature surveys were made with a traversing probe in the exhaust-nozzle flow for some confluent-flow configurations. The survey data at the mixing plane, plus the measured flow rates, were used to calculate the static-pressure variation along the exhaust nozzle length. The computed pressures compared well with experimental wall static-pressure data. External-flow surveys were made, for some confluent-flow configurations, with a large fixed rake at various locations in the exhaust plume.

  7. Emissions from queuing aircraft

    SciTech Connect

    Segal, H.

    1980-01-01

    The ability of the FAA (U.S. Federal Aviation Administration) Simplex mathematical model, which employs a simple point-source algorithm with provisions for selecting a particular plume height and initial box size for each aircraft being analyzed, to predict air quality through modeling emissions released from queuing aircraft was verified by measurements of carbon monoxide emissions from such aircraft during a five-day period at Los Angeles International Airport. The model predicted carbon monoxide concentrations of 4 ppm (National Ambient Air Quality Standard limit value is 35 ppm) at expected populated locations during the highest activity hour monitored. This study should also apply to other engine exhaust gases such as NO/sub x/.

  8. The effects of aircraft on climate and pollution. Part II: 20-year impacts of exhaust from all commercial aircraft worldwide treated individually at the subgrid scale.

    PubMed

    Jacobson, M Z; Wilkerson, J T; Naiman, A D; Lele, S K

    2013-01-01

    This study examines the 20-year impacts of emissions from all commercial aircraft flights worldwide on climate, cloudiness, and atmospheric composition. Aircraft emissions from each individual flight worldwide were modeled to evolve from the subgrid to grid scale with the global model described and evaluated in Part I of this study. Simulations with and without aircraft emissions were run for 20 years. Aircraft emissions were found to be responsible for -6% of Arctic surface global warming to date, -1.3% of total surface global warming, and -4% of global upper tropospheric warming. Arctic warming due to aircraft slightly decreased Arctic sea ice area. Longer simulations should result in more warming due to the further increase in CO2. Aircraft increased atmospheric stability below cruise altitude and decreased it above cruise altitude. The increase in stability decreased cumulus convection in favor of increased stratiform cloudiness. Aircraft increased total cloud fraction on average. Aircraft increased surface and upper tropospheric ozone by -0.4% and -2.5%, respectively and surface and upper-tropospheric peroxyacetyl nitrate (PAN) by -0.1% and -5%, respectively. Aircraft emissions increased tropospheric OH, decreasing column CO and CH4 by -1.7% and -0.9%, respectively. Aircraft emissions increased human mortality worldwide by -620 (-240 to 4770) deaths per year, with half due to ozone and the rest to particulate matter less than 2.5 micrometers in diameter (PM2.5). PMID:24601012

  9. 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...

  10. Summary of aircraft results for 1978 southeastern Virginia urban plume measurement study of ozone, nitrogen oxides, and methane

    NASA Technical Reports Server (NTRS)

    Gregory, G. L.; Wornom, D. E.; Mathis, J. J., Jr.; Sebacher, D. I.

    1980-01-01

    Ozone production was determined from aircraft and surface in situ measurements, as well as from an airborne laser absorption spectrometer. Three aircraft and approximately 10 surface stations provided air-quality data. Extensive meteorological, mixing-layer-height, and ozone-precursor data were also measured. Approximately 50 hrs (9 flight days) of data from the aircraft equipped to monitor ozone, nitrogen oxides, dewpoint temperature, and temperature are presented. In addition, each experiment conducted is discussed.

  11. 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.

  12. 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.

  13. Cart3D Analysis of Plume and Shock Interaction Effects on Sonic Boom

    NASA Technical Reports Server (NTRS)

    Castner, Raymond

    2015-01-01

    A plume and shock interaction study was developed to collect data and perform CFD on a configuration where a nozzle plume passed through the shock generated from the wing or tail of a supersonic vehicle. The wing or tail was simulated with a wedge-shaped shock generator. Three configurations were analyzed consisting of two strut mounted wedges and one propulsion pod with an aft deck from a low boom vehicle concept. Research efforts at NASA were intended to enable future supersonic flight over land in the United States. Two of these efforts provided data for regulatory change and enabled design of low boom aircraft. Research has determined that sonic boom is a function of aircraft lift and volume distribution. Through careful tailoring of these variables, the sonic boom of concept vehicles has been reduced. One aspect of vehicle tailoring involved how the aircraft engine exhaust interacted with aft surfaces on a supersonic aircraft, such as the tail and wing trailing edges. In this work, results from Euler CFD simulations are compared to experimental data collected on sub-scale components in a wind tunnel. Three configurations are studied to simulate the nozzle plume interaction with representative wing and tail surfaces. Results demonstrate how the plume and tail shock structure moves with increasing nozzle pressure ratio. The CFD captures the main features of the plume and shock interaction. Differences are observed in the plume and deck shock structure that warrant further research and investigation.

  14. Validation of scramjet exhaust simulation technique at Mach 6

    NASA Technical Reports Server (NTRS)

    Hopkins, H. B.; Konopka, W.; Leng, J.

    1979-01-01

    Current design philosophy for hydrogen-fueled, scramjet-powered hypersonic aircraft results in configurations with strong couplings between the engine plume and vehicle aerodynamics. The experimental verification of the scramjet exhaust simulation is described. The scramjet exhaust was reproduced for the Mach 6 flight condition by the detonation tube simulator. The exhaust flow pressure profiles, and to a large extent the heat transfer rate profiles, were then duplicated by cool gas mixtures of Argon and Freon 13B1 or Freon 12. The results of these experiments indicate that a cool gas simulation of the hot scramjet exhaust is a viable simulation technique except for phenomena which are dependent on the wall temperature relative to flow temperature.

  15. Airborne in-situ investigations of the Eyjafjallajökull volcanic ash plume on Iceland and over north-western Germany with light aircrafts and optical particle counters

    NASA Astrophysics Data System (ADS)

    Weber, K.; Eliasson, J.; Vogel, A.; Fischer, C.; Pohl, T.; van Haren, G.; Meier, M.; Grobéty, B.; Dahmann, D.

    2012-03-01

    During the time period of the eruption of the Icelandic volcano Eyjafjallajökull in April/May 2010 the Duesseldorf University of Applied Sciences has performed 14 research flights in situations with and without the volcanic ash plume over Germany. In parallel to the research flights in Germany three measurement flights have been performed by the University of Iceland in May 2010 over the western part of Iceland. During two of these flights the outskirts of the eruption plume were entered directly, delivering most direct measurements within the eruption plume during this eruptive event. For all the measurement flights reported here, light durable piston-motor driven aircrafts were used, which were equipped with optical particle counters for in-situ measurements. Real-time monitoring of the particle concentrations was possible during the flights. As different types of optical particle counters have been used in Iceland and Germany, the optical particle counters have been re-calibrated after the flights to the same standard using gravimetric reference methods and original Eyjafjallajökull volcanic ash samples. In-situ measurement results with high spatial resolution, directly from the eruption plume in Iceland as well as from the dispersed and several days old plume over Germany, are therefore presented here for the first time. They are normalized to the same ash concentration calibration standard. Moreover, airborne particles could be sampled directly out of the eruption plume in Iceland as well as during the flights over Germany. During the research flights over Iceland from 9 May 2011 to 11 May 2011 the ash emitted from the vent of the volcano turned out to be concentrated in a narrow well-defined plume of about 10 km width at a distance of 45-60 km away from the vent. Outside this plume the airborne ash concentrations could be proved to be below 50 μg m -3 over western Iceland. However, by entering the outskirts of the plume directly the research aircraft could

  16. Testing of lift/cruise fan exhaust deflector. [for a tip turbine lift fan in short takeoff aircraft

    NASA Technical Reports Server (NTRS)

    Schlundt, D. W.

    1975-01-01

    A lift/cruise exhaust deflector system for the LF336/A tip turbine lift fan was designed, built, and tested to determine the design and performance characteristics of a large-scale, single swivel nozzle thrust vectoring system. The exhaust deflector static testing was performed at the Ames Research Center outside static test stand facilities. The test hardware was installed on a hydraulic lift platform to permit both in and out of ground effect testing. The exhaust flow of the LF336/A lift fan was vectored from 0 degrees through 130 degrees during selected fan speeds to obtain performance at different operating conditions. The system was operated with and without flow vanes installed in the small radius bends to evaluate the system performance based on a proposed method of improving the internal flow losses. The program also included testing at different ground heights, to the nozzle exhaust plane, to obtain ground effect data, and the testing of two methods of thrust spoiling using a duct bypass door system and nozzle flap system.

  17. Calculations of economy of 18-cylinder radial aircraft engine with exhaust-gas turbine geared to the crankshaft

    NASA Technical Reports Server (NTRS)

    Hannum, Richard W; Zimmerman, Richard H

    1945-01-01

    Calculations based on dynamometer test-stand data obtained on an 18-cylinder radial engine were made to determine the improvement in fuel consumption that can be obtained at various altitudes by gearing an exhaust-gas turbine to the engine crankshaft in order to increase the engine-shaft work.

  18. Aircraft Fuel, Fuel Metering, Induction and Exhaust Systems (Course Outline), Aviation Mechanics (Power Plant): 9057.02.

    ERIC Educational Resources Information Center

    Dade County Public Schools, Miami, FL.

    This document presents an outline for a 135-hour course designed to help the trainee gain the skills and knowledge necessary to become an aviation powerplant mechanic. The course outlines the theory of operation of various fuel systems, fuel metering, induction, and exhaust system components with an emphasis on troubleshooting, maintenance, and…

  19. 40 CFR 87.31 - Standards for exhaust emissions.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 20 2010-07-01 2010-07-01 false Standards for exhaust emissions. 87.31... (CONTINUED) CONTROL OF AIR POLLUTION FROM AIRCRAFT AND AIRCRAFT ENGINES Exhaust Emissions (In-Use Aircraft Gas Turbine Engines) § 87.31 Standards for exhaust emissions. (a) Exhaust emissions of smoke from...

  20. Analysis of Nozzle Jet Plume Effects on Sonic Boom Signature

    NASA Technical Reports Server (NTRS)

    Bui, Trong

    2010-01-01

    An axisymmetric full Navier-Stokes computational fluid dynamics (CFD) study was conducted to examine nozzle exhaust jet plume effects on the sonic boom signature of a supersonic aircraft. A simplified axisymmetric nozzle geometry, representative of the nozzle on the NASA Dryden NF-15B Lift and Nozzle Change Effects on Tail Shock (LaNCETS) research airplane, was considered. The highly underexpanded nozzle flow is found to provide significantly more reduction in the tail shock strength in the sonic boom N-wave pressure signature than perfectly expanded and overexpanded nozzle flows. A tail shock train in the sonic boom signature, similar to what was observed in the LaNCETS flight data, is observed for the highly underexpanded nozzle flow. The CFD results provide a detailed description of the nozzle flow physics involved in the LaNCETS nozzle at different nozzle expansion conditions and help in interpreting LaNCETS flight data as well as in the eventual CFD analysis of a full LaNCETS aircraft. The current study also provided important information on proper modeling of the LaNCETS aircraft nozzle. The primary objective of the current CFD research effort was to support the LaNCETS flight research data analysis effort by studying the detailed nozzle exhaust jet plume s imperfect expansion effects on the sonic boom signature of a supersonic aircraft. Figure 1 illustrates the primary flow physics present in the interaction between the exhaust jet plume shock and the sonic boom coming off of an axisymmetric body in supersonic flight. The steeper tail shock from highly expanded jet plume reduces the dip of the sonic boom N-wave signature. A structured finite-volume compressible full Navier-Stokes CFD code was used in the current study. This approach is not limited by the simplifying assumptions inherent in previous sonic boom analysis efforts. Also, this study was the first known jet plume sonic boom CFD study in which the full viscous nozzle flow field was modeled, without

  1. Plume and Shock Interaction Effects on Sonic Boom in the 1-foot by 1-foot Supersonic Wind Tunnel

    NASA Technical Reports Server (NTRS)

    Castner, Raymond; Elmiligui, Alaa; Cliff, Susan; Winski, Courtney

    2015-01-01

    The desire to reduce or eliminate the operational restrictions of supersonic aircraft over populated areas has led to extensive research at NASA. Restrictions are due to the disturbance of the sonic boom, caused by the coalescence of shock waves formed by the aircraft. A study has been performed focused on reducing the magnitude of the sonic boom N-wave generated by airplane components with a focus on shock waves caused by the exhaust nozzle plume. Testing was completed in the 1-foot by 1-foot supersonic wind tunnel to study the effects of an exhaust nozzle plume and shock wave interaction. The plume and shock interaction study was developed to collect data for computational fluid dynamics (CFD) validation of a nozzle plume passing through the shock generated from the wing or tail of a supersonic vehicle. The wing or tail was simulated with a wedgeshaped shock generator. This test entry was the first of two phases to collect schlieren images and off-body static pressure profiles. Three wedge configurations were tested consisting of strut-mounted wedges of 2.5- degrees and 5-degrees. Three propulsion configurations were tested simulating the propulsion pod and aft deck from a low boom vehicle concept, which also provided a trailing edge shock and plume interaction. Findings include how the interaction of the jet plume caused a thickening of the shock generated by the wedge (or aft deck) and demonstrate how the shock location moved with increasing nozzle pressure ratio.

  2. Characterization of the exhaust particulates in the ground cloud and high-altitude plume of large solid-propellant booster rockets

    NASA Technical Reports Server (NTRS)

    Strand, L. D.; Bowyer, J. M.; Varsi, G.; Laue, E. G.; Gauldin, R.

    1980-01-01

    The report is concerned with the characterization of Al2O3 particles in the atmosphere. These particles comprise one of the major combustion products of the rocket propellant employed in the Space Shuttle boosters. A ground cloud and stratospheric plume are considered. It is concluded that the typical residence times in the atmosphere are much longer than earlier estimates have indicated.

  3. Real-time and integrated measurement of potential human exposure to particle-bound polycyclic aromatic hydrocarbons (PAHs) from aircraft exhaust.

    PubMed Central

    Childers, J W; Witherspoon, C L; Smith, L B; Pleil, J D

    2000-01-01

    We used real-time monitors and low-volume air samplers to measure the potential human exposure to airborne polycyclic aromatic hydrocarbon (PAH) concentrations during various flight-related and ground-support activities of C-130H aircraft at an Air National Guard base. We used three types of photoelectric aerosol sensors (PASs) to measure real-time concentrations of particle-bound PAHs in a break room, downwind from a C-130H aircraft during a four-engine run-up test, in a maintenance hangar, in a C-130H aircraft cargo bay during cargo-drop training, downwind from aerospace ground equipment (AGE), and in a C-130H aircraft cargo bay during engine running on/off (ERO) loading and backup exercises. Two low-volume air samplers were collocated with the real-time monitors for all monitoring events except those in the break room and during in-flight activities. Total PAH concentrations in the integrated-air samples followed a general trend: downwind from two AGE units > ERO-loading exercise > four-engine run-up test > maintenance hangar during taxi and takeoff > background measurements in maintenance hangar. Each PAH profile was dominated by naphthalene, the alkyl-substituted naphthalenes, and other PAHs expected to be in the vapor phase. We also found particle-bound PAHs, such as fluoranthene, pyrene, and benzo[a]pyrene in some of the sample extracts. During flight-related exercises, total PAH concentrations in the integrated-air samples were 10-25 times higher than those commonly found in ambient air. Real-time monitor mean responses generally followed the integrated-air sample trends. These monitors provided a semiquantitative temporal profile of ambient PAH concentrations and showed that PAH concentrations can fluctuate rapidly from a baseline level < 20 to > 4,000 ng/m(3) during flight-related activities. Small handheld models of the PAS monitors exhibited potential for assessing incidental personal exposure to particle-bound PAHs in engine exhaust and for serving as

  4. Real-time and integrated measurement of potential human exposure to particle-bound polycyclic aromatic hydrocarbons (PAHs) from aircraft exhaust.

    PubMed

    Childers, J W; Witherspoon, C L; Smith, L B; Pleil, J D

    2000-09-01

    We used real-time monitors and low-volume air samplers to measure the potential human exposure to airborne polycyclic aromatic hydrocarbon (PAH) concentrations during various flight-related and ground-support activities of C-130H aircraft at an Air National Guard base. We used three types of photoelectric aerosol sensors (PASs) to measure real-time concentrations of particle-bound PAHs in a break room, downwind from a C-130H aircraft during a four-engine run-up test, in a maintenance hangar, in a C-130H aircraft cargo bay during cargo-drop training, downwind from aerospace ground equipment (AGE), and in a C-130H aircraft cargo bay during engine running on/off (ERO) loading and backup exercises. Two low-volume air samplers were collocated with the real-time monitors for all monitoring events except those in the break room and during in-flight activities. Total PAH concentrations in the integrated-air samples followed a general trend: downwind from two AGE units > ERO-loading exercise > four-engine run-up test > maintenance hangar during taxi and takeoff > background measurements in maintenance hangar. Each PAH profile was dominated by naphthalene, the alkyl-substituted naphthalenes, and other PAHs expected to be in the vapor phase. We also found particle-bound PAHs, such as fluoranthene, pyrene, and benzo[a]pyrene in some of the sample extracts. During flight-related exercises, total PAH concentrations in the integrated-air samples were 10-25 times higher than those commonly found in ambient air. Real-time monitor mean responses generally followed the integrated-air sample trends. These monitors provided a semiquantitative temporal profile of ambient PAH concentrations and showed that PAH concentrations can fluctuate rapidly from a baseline level < 20 to > 4,000 ng/m(3) during flight-related activities. Small handheld models of the PAS monitors exhibited potential for assessing incidental personal exposure to particle-bound PAHs in engine exhaust and for serving as

  5. Preliminary Analysis of the Effect of Flow Separation Due to Rocket Jet Pluming on Aircraft Dynamic Stability During Atmospheric Exit

    NASA Technical Reports Server (NTRS)

    Dryer, Murray; North, Warren J.

    1959-01-01

    A theoretical investigation was conducted to determine the effects of body boundary-layer separation resulting from a highly underexpanded jet on the dynamic stability of a typical rocket aircraft during an atmospheric exit trajectory. The particular flight condition studied on a digital computer for five degrees of freedom was at Mach 6.0 and 150,000 feet. In view of the unknown character of the separated flow field, two estimates of the pressures in the separated region were made to calculate the unbalanced forces and moments. These estimates, based on limited fundamental zero-angle-of-attack studies and observations, are believed to cover what may be the actual case. In addition to a fixed control case, two simulated pilot control inputs were studied: rate-limited and instantaneous responses. The resulting-motions with and without boundary-layer separation were compared for various initial conditions. The lower of the assumed misalinement forces and moments led to a situation whereby a slowly damped motion could be satisfactorily controlled with rate-limited control input. The higher assumption led to larger amplitude, divergent motions when the same control rates were used. These motions were damped only when the instantaneous control responses were assumed.

  6. Comparison of the Chemical and Physical Evolution and Characteristics of 495 Biomass Burning Plumes Intercepted by the NASA DC-8 Aircraft during the ARCTAS/CARB-2008 Field Campaign

    NASA Astrophysics Data System (ADS)

    Hecobian, A.; Weber, R.; Jimenez, J. L.; Vay, S. A.; Diskin, G. S.; Sachse, G. W.; Wisthaler, A.

    2009-12-01

    Biomass burning events include anthropogenic burning, such as bio-fuel or prescribed burning, and natural fires. Emissions from either type of burning are a significant source for a wide range of atmospheric trace gases and aerosol particles that can have important health and climate impacts.This study compares the different chemical and aerosol components of 495 biomass-burning plumes that were intercepted by the NASA DC-8 research aircraft during the three phases of the Arctic Research of the Composition of the Troposphere from Aircraft and Satellite (ARCTAS) experiment. The ARCTAS experiment was conducted in three phases: ARCTAS-A, based out of Fairbanks, Alaska, U.S.A. (3 to 19 April, 2008); ARCTAS-B based out of Cold Lake, Alberta, Canada (29 June to 13 July, 2008); and ARCTAS-CARB, based out of Palmdale, California, U.S.A. (18 to 24 June, 2008). Many different fire emissions were intercepted during this study. The plumes were classified into different categories: Plumes that were present due to long range transport from their source of emission were categorized into Asian, Siberian, European and a mix of Asian and Siberian plumes. Boreal fires from ARCTAS-B were divided into two groups: Fresh and Aged. This was based on the transport age of the plumes from the location of the plume intercept to the source of emission. During ARCTAS-CARB, biomass-burning emissions were segregated into two main categories: those that were influence by urban emissions versus the plumes that had smaller urban emission influences. Each of the ARCTAS-CARB plume categories noted above were further subdivided into fresh or more aged plumes. A statistical summary of the emission or enhancement ratios based on changes relative to CO, for various trace gas species and aerosol chemical components was produced for each smoke plume category. A high degree of variability in emission ratios was observed for all types of plumes; however, the following conclusions were formulated after a

  7. Modeling the formation and properties of traditional and non-traditional secondary organic aerosol: problem formulation and application to aircraft exhaust

    NASA Astrophysics Data System (ADS)

    Jathar, S. H.; Miracolo, M. A.; Presto, A. A.; Donahue, N. M.; Adams, P. J.; Robinson, A. L.

    2012-10-01

    We present a methodology to model secondary organic aerosol (SOA) formation from the photo-oxidation of unspeciated low-volatility organics (semi-volatile and intermediate volatile organic compounds) emitted by combustion systems. It is formulated using the volatility basis-set approach. Unspeciated low-volatility organics are classified by volatility and then allowed to react with the hydroxyl radical. The new methodology allows for larger reductions in volatility with each oxidation step than previous volatility basis set models, which is more consistent with the addition of common functional groups and similar to those used by traditional SOA models. The methodology is illustrated using data collected during two field campaigns that characterized the atmospheric evolution of dilute gas-turbine engine emissions using a smog chamber. In those experiments, photo-oxidation formed a significant amount of SOA, much of which could not be explained based on the emissions of traditional speciated precursors; we refer to the unexplained SOA as non-traditional SOA (NT-SOA). The NT-SOA can be explained by emissions of unspeciated low-volatility organics measured using sorbents. We show that the parameterization proposed by Robinson et al. (2007) is unable to explain the timing of the NT-SOA formation in the aircraft experiments because it assumes a very modest reduction in volatility of the precursors with every oxidation reaction. In contrast the new method better reproduces the NT-SOA formation. The NT-SOA yields estimated for the unspeciated low-volatility organic emissions in aircraft exhaust are similar to literature data for large n-alkanes and other low-volatility organics. The estimated yields vary with fuel composition (Jet Propellent-8 versus Fischer-Tropsch) and engine load (ground idle versus non-ground idle). The framework developed here is suitable for modeling SOA formation from emissions from other combustion systems.

  8. Liquid Booster Module (LBM) plume flowfield model

    NASA Technical Reports Server (NTRS)

    Smith, S. D.

    1981-01-01

    A complete definition of the LBM plume is important for many Shuttle design criteria. The exhaust plume shape has a significant effect on the vehicle base pressure. The LBM definition is also important to the Shuttle base heating, aerodynamics and the influence of the exhaust plume on the launch stand and environment. For these reasons a knowledge of the LBM plume characteristics is necessary. A definition of the sea level LBM plume as well as at several points along the Shuttle trajectory to LBM, burnout is presented.

  9. A Preliminary Study of the Prevention of Ice on Aircraft by the Use of Engine-exhaust Heat

    NASA Technical Reports Server (NTRS)

    Rodert, Lewis A

    1939-01-01

    An investigation was made in the N.A.C.A. ice tunnel at air temperatures from 20 degrees to 28 degrees Fahrenheit and at a velocity of 80 miles per hour to determine whether ice formations on a model wing could be prevented by the use of the heat from the engine-exhaust gas. Various spanwise duct systems were tested in a 6-foot-chord N.A.C.A. 23012 wing model. The formation of ice over the entire wing chord was prevented by the direct heating of the forward 10 percent of the wing by hot air, which was passed through leading-edge ducts. Under dry conditions, enough heat to maintain the temperature of the forward 10 percent of the wing at about 200 degrees Fahrenheit above that of the ambient air was required for the prevention of ice formation. The air temperature in the ducts that was necessary to produce these skin temperatures varied from 360 degrees to 834 degrees Fahrenheit; the corresponding air velocities in the duct were 152 and 45 feet per second. Ice formations at the leading edge were locally prevented by air that passed over the interior of the wing surface at a velocity of 30 feet per second and a temperature of 122 degrees Fahrenheit.

  10. Volcanic Plume Measurements with UAV (Invited)

    NASA Astrophysics Data System (ADS)

    Shinohara, H.; Kaneko, T.; Ohminato, T.

    2013-12-01

    Volatiles in magmas are the driving force of volcanic eruptions and quantification of volcanic gas flux and composition is important for the volcano monitoring. Recently we developed a portable gas sensor system (Multi-GAS) to quantify the volcanic gas composition by measuring volcanic plumes and obtained volcanic gas compositions of actively degassing volcanoes. As the Multi-GAS measures variation of volcanic gas component concentrations in the pumped air (volcanic plume), we need to bring the apparatus into the volcanic plume. Commonly the observer brings the apparatus to the summit crater by himself but such measurements are not possible under conditions of high risk of volcanic eruption or difficulty to approach the summit due to topography etc. In order to overcome these difficulties, volcanic plume measurements were performed by using manned and unmanned aerial vehicles. The volcanic plume measurements by manned aerial vehicles, however, are also not possible under high risk of eruption. The strict regulation against the modification of the aircraft, such as installing sampling pipes, also causes difficulty due to the high cost. Application of the UAVs for the volcanic plume measurements has a big advantage to avoid these problems. The Multi-GAS consists of IR-CO2 and H2O gas analyzer, SO2-H2O chemical sensors and H2 semiconductor sensor and the total weight ranges 3-6 kg including batteries. The necessary conditions of the UAV for the volcanic plumes measurements with the Multi-GAS are the payloads larger than 3 kg, maximum altitude larger than the plume height and installation of the sampling pipe without contamination of the exhaust gases, as the exhaust gases contain high concentrations of H2, SO2 and CO2. Up to now, three different types of UAVs were applied for the measurements; Kite-plane (Sky Remote) at Miyakejima operated by JMA, Unmanned airplane (Air Photo Service) at Shinomoedake, Kirishima volcano, and Unmanned helicopter (Yamaha) at Sakurajima

  11. Direct measurements of HONO and NO2 by tunable infrared differential absorption spectroscopy; Results from two field campaigns sampling aircraft exhaust and ambient urban air

    NASA Astrophysics Data System (ADS)

    Lee, B. H.; Santoni, G.; Herndon, S. C.; Wood, E. C.; Miake-Lye, R. C.; Munger, J. W.; Wofsy, S. C.; Zahniser, M. S.; McManus, J. B.; Nelson, D. D.

    2009-12-01

    Nitrous acid (HONO) is an important source of hydroxyl radicals (OH), the main oxidizing agent in the atmosphere. However, gaseous HONO has historically proven difficult to measure accurately and to date there is no standard technique. We describe a new instrument capable of high-frequency measurements of HONO and nitrogen dioxide (NO2) mixing ratios by tunable infrared differential absorption spectrometry. Mid-infrared light from two continuous-wave mode quantum cascade lasers traverse a 210 m path through a multi-pass astigmatic cell at reduced pressures for the direct detection of HONO (1660 cm-1) and NO2 (1604 cm-1). We achieve an absorbance precision less than 3×10-6 Hz-1 in one second, which translates to detection limits (S/N=3) of 300 and 30 ppt for HONO and NO2, respectively, in one second. Both lasers and the detector are thermoelectrically cooled, facilitating long-term unattended measurements. We also report preliminary results from two field campaigns; the Alternative Aviation Fuels Experiment (AAFEX) and the Study of Houston Air Radical Precursors (SHARP). At AAFEX, HONO emission ratios relative to CO2 and NOy observed in commercial aircraft exhaust are larger than in most other combustion sources and likely to play a significant role in regional HOx chemistry. Preliminary analysis from the SHARP campaign shows good agreement in HONO and NO2 levels between various measurement techniques.

  12. 40 CFR 87.31 - Standards for exhaust emissions.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... (CONTINUED) Definitions. Exhaust Emissions (In-Use Aircraft Gas Turbine Engines) § 87.31 Standards for exhaust emissions. (a) Exhaust emissions of smoke from each in-use aircraft gas turbine engine of Class T8... in-use aircraft gas turbine engine of class TF and of rated output of 129 kilonewtons thrust...

  13. 14 CFR 34.31 - Standards for exhaust emissions.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... FUEL VENTING AND EXHAUST EMISSION REQUIREMENTS FOR TURBINE ENGINE POWERED AIRPLANES Exhaust Emissions (In-use Aircraft Gas Turbine Engines) § 34.31 Standards for exhaust emissions. (a) Exhaust emissions of smoke from each in-use aircraft gas turbine engine of Class T8, beginning February 1, 1974,...

  14. 14 CFR 34.21 - Standards for exhaust emissions.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... FUEL VENTING AND EXHAUST EMISSION REQUIREMENTS FOR TURBINE ENGINE POWERED AIRPLANES Exhaust Emissions (New Aircraft Gas Turbine Engines) § 34.21 Standards for exhaust emissions. (a) Exhaust emissions of smoke from each new aircraft gas turbine engine of class T8 manufactured on or after February 1,...

  15. 14 CFR 34.31 - Standards for exhaust emissions.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... FUEL VENTING AND EXHAUST EMISSION REQUIREMENTS FOR TURBINE ENGINE POWERED AIRPLANES Exhaust Emissions (In-use Aircraft Gas Turbine Engines) § 34.31 Standards for exhaust emissions. (a) Exhaust emissions of smoke from each in-use aircraft gas turbine engine of Class T8, beginning February 1, 1974,...

  16. 14 CFR 34.31 - Standards for exhaust emissions.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... FUEL VENTING AND EXHAUST EMISSION REQUIREMENTS FOR TURBINE ENGINE POWERED AIRPLANES Exhaust Emissions (In-use Aircraft Gas Turbine Engines) § 34.31 Standards for exhaust emissions. (a) Exhaust emissions of smoke from each in-use aircraft gas turbine engine of Class T8, beginning February 1, 1974,...

  17. 14 CFR 34.31 - Standards for exhaust emissions.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... FUEL VENTING AND EXHAUST EMISSION REQUIREMENTS FOR TURBINE ENGINE POWERED AIRPLANES Exhaust Emissions (In-use Aircraft Gas Turbine Engines) § 34.31 Standards for exhaust emissions. (a) Exhaust emissions of smoke from each in-use aircraft gas turbine engine of Class T8, beginning February 1, 1974,...

  18. 14 CFR 34.31 - Standards for exhaust emissions.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... FUEL VENTING AND EXHAUST EMISSION REQUIREMENTS FOR TURBINE ENGINE POWERED AIRPLANES Exhaust Emissions (In-use Aircraft Gas Turbine Engines) § 34.31 Standards for exhaust emissions. (a) Exhaust emissions of smoke from each in-use aircraft gas turbine engine of Class T8, beginning February 1, 1974,...

  19. Aircraft sulfur emissions and the formation of visible contrails

    NASA Astrophysics Data System (ADS)

    Brown, R. C.; Miake-Lye, R. C.; Anderson, M. R.; Kolb, C. E.

    Contrail formation in the exhaust plume of the ATTAS aircraft engine burning fuels with 2 ppmm and 266 ppmm sulfur has been studied using an aerosol dynamics model coupled to a 2-dimensional, axisymmetric flow code. For both the low and high sulfur fuels, the model predicted approximately 35% of the available water condenses within 200 m downstream of the exhaust exit. However, particle size distributions for the low sulfur plume are broader and extend to larger sizes. Model results indicate that, for the engine and flight conditions treated, sulfuric acid is a viable soot activating agent when the fuel sulfur mass loading is reduced to 2 ppmm and that differences in the contrail particle size distribution for sulfur mass loadings between 2 ppmm and 266 ppmm would be difficult to detect.

  20. On the mechanisms controlling the formation and properties of volatile particles in aircraft wakes

    NASA Astrophysics Data System (ADS)

    Yu, Fangqun; Turco, Richard P.; Kärcher, Bernd; Schröder, Franz P.

    New observations taken in aircraft wakes, including the DLR ATTAS, provide strong constraints on models of aircraft plume aerosols. Using a comprehensive microphysics code, we have performed sensitivity studies to identify the key microphysical mechanisms acting in such plumes. Analysis of these simulations reveals that the largest volatile plume particles—those most likely to contribute to the background abundance of condensation nuclei—are dominated by ion-mode particles when chemiions are included. Moreover, such modeling demonstrates that standard treatments of plume microphysics—in the absence of chemiions—fails to explain field measurements. The principal factor controlling the population of ultrafine plume particles is the number of chemiions emitted by the aircraft engines. Since the ions are a byproduct of the combustion itself, and their abundance in the exhaust stream is controlled by ion-ion recombination, the initial ion concentrations—and so the eventual emission indices for ion-mode particles—are expected to be relatively invariant. Our results indicate that reductions in fuel sulfur content, while not likely to lower the total number of volatile particles emitted, would decrease the size of the ion-mode particles in fresh aircraft wakes, reducing their atmospheric lifetimes and potential environmental effects.

  1. Validation of Inlet and Exhaust Boundary Conditions for a Cartesian Method

    NASA Technical Reports Server (NTRS)

    Pandya, Shishir A.; Murman, Scott M.; Aftosmis, Michael J.

    2004-01-01

    Inlets and exhaust nozzles are often omitted in aerodynamic simulations of aircraft due to the complexities involved in the modeling of engine details and flow physics. However, the omission is often improper since inlet or plume flows may have a substantial effect on vehicle aerodynamics. A method for modeling the effect of inlets and exhaust plumes using boundary conditions within an inviscid Cartesian flow solver is presented. This approach couples with both CAD systems and legacy geometry to provide an automated tool suitable for parameter studies. The method is validated using two and three-dimensional test problems which are compared with both theoretical and experimental results. The numerical results demonstrate excellent agreement with theory and available data, even for extremely strong jets and very sensitive inlets.

  2. A unified model for ultrafine aircraft particle emissions

    NASA Astrophysics Data System (ADS)

    Kärcher, B.; Turco, R. P.; Yu, F.; Danilin, M. Y.; Weisenstein, D. K.; Miake-Lye, R. C.; Busen, R.

    2000-12-01

    To predict the environmental impacts of commercial aviation, intensive studies have been launched to measure the properties and effects of aircraft emissions. These observations have revealed an extremely wide variance with respect to the number and sizes of the particles produced in the exhaust plumes. An analytic parameterization is presented that explains most of the observational variance. It is shown that the observed scatter in emission indices of volatile particles is due mainly to variations of plume age, the detection threshold size of the particle counters, and condensable organic emissions. The principle trend of the volatile particle concentrations with fuel sulfur content can be explained with conversion fractions of sulfur into particulate sulfuric acid at emission within the range 0.5 to 5%. A novel assessment of the perturbation of the stratospheric aerosol layer by a future supersonic aircraft fleet confirms previous estimates and puts these simulations on a sounder physical basis.

  3. Orbital Maneuvering Vehicle (OMV) plume and plume effects study

    NASA Technical Reports Server (NTRS)

    Smith, Sheldon D.

    1991-01-01

    The objective was to characterize the Orbital Maneuvering Vehicle (OMV) propulsion and attitude control system engine exhaust plumes and predict the resultant plume impingement pressure, heat loads, forces, and moments. Detailed description is provided of the OMV gaseous nitrogen (GN2) thruster exhaust plume flow field characteristics calculated with the RAMP2 snd SFPGEN computer codes. Brief descriptions are included of the two models, GN2 thruster characteristics and RAMP2 input data files. The RAMP2 flow field could be recalculated by other organizations using the information presented. The GN2 flow field can be readily used by other organizations who are interested in GN2 plume induced environments which require local flow field properties which can be supplied using the SFPGEN GN2 model.

  4. In-Situ Microphysical Measurements In Rocket Plumes With The Cloud And Aerosol Spectrometer (CAS)

    NASA Astrophysics Data System (ADS)

    Kok, G.; Baumgardner, D.; Avallone, L.; Kalnajs, L.; Herman, R.; Ross, M.; Thompson, T.; Toohey, D.

    2005-12-01

    High resolution, single particle measurements have been made in rocket plumes using an optical particle spectrometer that measures diameters from 0.5 to 44 um. The Cloud and Aerosol Spectrometer (CAS) measures the light scattered in two directions from individual particles that pass through a focused, 680 nm laser beam and we derive the diameter, shape and composition from this information. The CAS was mounted on the NASA WB57-F aircraft as part of the Plume Ultrafast Measurements Acquisition (PUMA) project, an experiment funded by NSF and NASA to study the chemistry and microphysics of rocket plumes. Measurements were first made in a plume generated by an Atlas IIAS rocket in May, 2004 and again in July, 2005 in the plume formed from the exhaust of the solid state boosters used to launch the space shuttle Discovery into orbit. The microstructure of the two plumes and the characteristics of their particles were distinctly different. The two cases had similar maximum concentrations of 300 cm-3, but the space shuttle particles were on average larger and a greater percentage of them were irregular in shape. An analysis of the distance between particles suggests clustering because of the non-Poisson shape of the frequency distribution of inter-arrival times.

  5. Results of an investigation of jet plume effects on an 0.010-scale model (75-OTS) of the space shuttle integrated vehicle in the 9 x 7-foot leg of the NASA/Ames unitary wind tunnel (IA82B), volume 1. [an exhaust flow simulation

    NASA Technical Reports Server (NTRS)

    Hawthorne, P. J.

    1976-01-01

    The base pressure environment was investigated for the first and second stage mated vehicle in a supersonic flow field from Mach 1.55 through 2.20 with simulated rocket engine exhaust plumes. The pressure environment was investigated for the orbiter at various vent port locations at these same freestream conditions. The Mach number environment around the base of the model with rocket plumes simulated was examined. Data were obtained at angles of attack from -4 deg through +4 deg at zero yaw, and at yaw angles from -4 deg through +4 deg at zero angle of attack, with rocket plume sizes varying from smaller than nominal to much greater than nominal. Failed orbiter engine data were also obtained. Elevon hinge moments and wing panel load data were obtained during all runs. Photographs of the tested configurations are shown.

  6. 14 CFR 23.1123 - Exhaust system.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 14 Aeronautics and Space 1 2014-01-01 2014-01-01 false Exhaust system. 23.1123 Section 23.1123 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT AIRWORTHINESS... Exhaust system. (a) Each exhaust system must be fireproof and corrosion-resistant, and must have means...

  7. 14 CFR 23.1123 - Exhaust system.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 14 Aeronautics and Space 1 2011-01-01 2011-01-01 false Exhaust system. 23.1123 Section 23.1123 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT AIRWORTHINESS... Exhaust system. (a) Each exhaust system must be fireproof and corrosion-resistant, and must have means...

  8. 14 CFR 23.1123 - Exhaust system.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 14 Aeronautics and Space 1 2012-01-01 2012-01-01 false Exhaust system. 23.1123 Section 23.1123 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT AIRWORTHINESS... Exhaust system. (a) Each exhaust system must be fireproof and corrosion-resistant, and must have means...

  9. 14 CFR 23.1123 - Exhaust system.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 14 Aeronautics and Space 1 2013-01-01 2013-01-01 false Exhaust system. 23.1123 Section 23.1123 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT AIRWORTHINESS... Exhaust system. (a) Each exhaust system must be fireproof and corrosion-resistant, and must have means...

  10. 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. PMID:16903278

  11. 40 CFR 87.31 - Standards for exhaust emissions.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... Gas Turbine Engines) § 87.31 Standards for exhaust emissions. (a) Exhaust emissions of smoke from each in-use aircraft gas turbine engine of Class T8, beginning February 1, 1974, shall not exceed: Smoke number of 30. (b) Exhaust emissions of smoke from each in-use aircraft gas turbine engine of class TF...

  12. 14 CFR 34.21 - Standards for exhaust emissions.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 14 Aeronautics and Space 1 2012-01-01 2012-01-01 false Standards for exhaust emissions. 34.21 Section 34.21 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT FUEL VENTING AND EXHAUST EMISSION REQUIREMENTS FOR TURBINE ENGINE POWERED AIRPLANES Exhaust Emissions (New Aircraft Gas Turbine Engines) §...

  13. 40 CFR 87.31 - Standards for exhaust emissions.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... Gas Turbine Engines) § 87.31 Standards for exhaust emissions. (a) Exhaust emissions of smoke from each in-use aircraft gas turbine engine of Class T8, beginning February 1, 1974, shall not exceed: Smoke number of 30. (b) Exhaust emissions of smoke from each in-use aircraft gas turbine engine of class TF...

  14. 40 CFR 87.31 - Standards for exhaust emissions.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... Gas Turbine Engines) § 87.31 Standards for exhaust emissions. (a) Exhaust emissions of smoke from each in-use aircraft gas turbine engine of Class T8, beginning February 1, 1974, shall not exceed: Smoke number of 30. (b) Exhaust emissions of smoke from each in-use aircraft gas turbine engine of class TF...

  15. IR sensor design insight from missile-plume prediction models

    NASA Astrophysics Data System (ADS)

    Rapanotti, John L.; Gilbert, Bruno; Richer, Guy; Stowe, Robert

    2002-08-01

    Modern anti-tank missiles and the requirement of rapid deployment have significantly reduced the use of passive armour in protecting land vehicles. Vehicle survivability is becoming more dependent on sensors, computers and countermeasures to detect and avoid threats. An analysis of missile propellants suggests that missile detection based on plume characteristics alone may be more difficult than anticipated. Currently, the passive detection of missiles depends on signatures with a significant ultraviolet component. This approach is effective in detecting anti-aircraft missiles that rely on powerful motors to pursue high-speed aircraft. The high temperature exhaust from these missiles contains significant levels of carbon dioxide, water and, often, metal oxides such as alumina. The plumes emits strongest in the infrared, 1 to 5micrometers , regions with a significant component of the signature extending into the ultraviolet domain. Many anti-tank missiles do not need the same level of propulsion and radiate significantly less. These low velocity missiles, relying on the destructive force of shaped-charge warhead, are more difficult to detect. There is virtually no ultraviolet component and detection based on UV sensors is impractical. The transition in missile detection from UV to IR is reasonable, based on trends in imaging technology, but from the analysis presented in this paper even IR imagers may have difficulty in detecting missile plumes. This suggests that the emphasis should be placed in the detection of the missile hard body in the longer wavelengths of 8 to 12micrometers . The analysis described in this paper is based on solution of the governing equations of plume physics and chemistry. These models will be used to develop better sensors and threat detection algorithms.

  16. Low altitude plume impingement handbook

    NASA Technical Reports Server (NTRS)

    Smith, Sheldon D.

    1991-01-01

    Plume Impingement modeling is required whenever an object immersed in a rocket exhaust plume must survive or remain undamaged within specified limits, due to thermal and pressure environments induced by the plume. At high altitudes inviscid plume models, Monte Carlo techniques along with the Plume Impingement Program can be used to predict reasonably accurate environments since there are usually no strong flowfield/body interactions or atmospheric effects. However, at low altitudes there is plume-atmospheric mixing and potential large flowfield perturbations due to plume-structure interaction. If the impinged surface is large relative to the flowfield and the flowfield is supersonic, the shock near the surface can stand off the surface several exit radii. This results in an effective total pressure that is higher than that which exists in the free plume at the surface. Additionally, in two phase plumes, there can be strong particle-gas interaction in the flowfield immediately ahead of the surface. To date there have been three levels of sophistication that have been used for low altitude plume induced environment predictions. Level 1 calculations rely on empirical characterizations of the flowfield and relatively simple impingement modeling. An example of this technique is described by Piesik. A Level 2 approach consists of characterizing the viscous plume using the SPF/2 code or RAMP2/LAMP and using the Plume Impingement Program to predict the environments. A Level 3 analysis would consist of using a Navier-Stokes code such as the FDNS code to model the flowfield and structure during a single calculation. To date, Level 1 and Level 2 type analyses have been primarily used to perform environment calculations. The recent advances in CFD modeling and computer resources allow Level 2 type analysis to be used for final design studies. Following some background on low altitude impingement, Level 1, 2, and 3 type analysis will be described.

  17. Predicting Aircraft Noise Levels

    NASA Technical Reports Server (NTRS)

    Clark, B. J.

    1983-01-01

    Computer program developed for predicting aircraft noise levels either in flight or in ground tests. Noise sources include fan inlet and exhaust jet flap (for powered lift), core (combustor), turbine and airframe. Program written in FORTRAN IV.

  18. Transmittance and Radiance Computations for Rocket Engine Plume Environments

    NASA Technical Reports Server (NTRS)

    Tejwani, Gopal D.

    2003-01-01

    Emission and absorption characteristics of several atmospheric and combustion species have been studied and are presented with reference to rocket engine plume environments. The effects of clous, rain, and fog on plume radiance/transmittance has also been studied.Preliminary results for the radiance from the exhaust plume of the space shuttle main engine are shown and discussed.

  19. Soot aerosol in the lower stratosphere: Pole-to-pole variability and contributions by aircraft

    NASA Astrophysics Data System (ADS)

    Pueschel, R. F.; Boering, K. A.; Verma, S.; Howard, S. D.; Ferry, G. V.; Goodman, J.; Allen, D. A.; Hamill, P.

    1997-06-01

    A NASA ER-2 high-altitude research aircraft intercepted the exhaust wake of a supersonic Concorde aircraft in the stratosphere near New Zealand on October 8, 1994. Black carbon (soot) aerosol (BCA) was sampled by wire impactors during the first five of 12 short-duration wake intercepts. BCA concentration in Concorde exhaust at 16.3 km altitude was 0.2 particles cm-3, the size distribution peaked at a geometric mean radius of 0.09 μm, and the mass loading was 2.0±1.4 ng m-3. With a plume dilution factor (DF) of 1.0×10-5, determined by the ratio of CO2 measured in the plume (above the ambient stratospheric background level) to CO2 in the engine exhaust plane, the Concorde BCA emission index was EI(BCA)=0.07±0.05 g BCA per kg fuel burned. Applying this EI to estimates of aircraft fuel burned by the current subsonic fleet in the stratosphere yields average stratospheric BCA loadings of 0.5 ng m-3, commensurate with observations in the northern stratosphere. Applying the Concorde EI to fuel consumption by a projected future fleet suggests a twofold-threefold increase of stratospheric BCA by the year 2015. A strong gradient in BCA concentration exists between the northern and the southern hemispheres, indicating interhemispheric mixing times longer than stratospheric residence times.

  20. 14 CFR 25.1127 - Exhaust driven turbo-superchargers.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Exhaust driven turbo-superchargers. 25.1127... AIRCRAFT AIRWORTHINESS STANDARDS: TRANSPORT CATEGORY AIRPLANES Powerplant Exhaust System § 25.1127 Exhaust driven turbo-superchargers. (a) Each exhaust driven turbo-supercharger must be approved or shown to...

  1. Results of an investigation of jet plume effects on a 0.010-scale model (75-OTS) of the space shuttle integrated vehicle in the 8 x 7-foot leg of the NASA/Ames unitary wind tunnel (IA82C), volume 1. [(an exhaust flow simulation)

    NASA Technical Reports Server (NTRS)

    Hawthorne, P. J.

    1976-01-01

    The primary test objective was to define the base pressure environment of the first and second stage mated vehicle in a supersonic flow field from Mach 2.60 through 3.50 with simulated rocket engine exhaust plumes. The secondary objective was to obtain the pressure environment of the Orbiter at various vent port locations at these same freestream conditions. Data were obtained at angles of attack from -4 deg through +4 deg at zero yaw, and at yaw angles from -4 deg through +4 deg at zero angle of attack, with rocket plume sizes varying from smaller than nominal to much greater than nominal. Failed Orbiter engine data were also obtained. Elevon hinge moments and wing panel load data were obtained during all runs. Photographs of test equipment and tested configurations are shown.

  2. The effects of aircraft on climate and pollution. Part I: Numerical methods for treating the subgrid evolution of discrete size- and composition-resolved contrails from all commercial flights worldwide

    NASA Astrophysics Data System (ADS)

    Jacobson, M. Z.; Wilkerson, J. T.; Naiman, A. D.; Lele, S. K.

    2011-06-01

    This paper provides and evaluates mass conservative, positive-definite, unconditionally-stable, and non-iterative numerical techniques for simulating the evolution of discrete, size- and composition-resolved aerosol and contrail particles in individual aircraft exhaust plumes in a global or regional 3-D atmospheric model and coupling the subgrid exhaust plume information to the grid scale. Such treatment represents a new method of simulating the effects of aircraft on climate, contrails, and atmospheric composition. Microphysical processes solved within each plume include size-resolved coagulation among and between aerosol and contrail particles and their inclusions, aerosol-to-hydrometeor particle ice and liquid nucleation, deposition/sublimation, and condensation/evaporation. Each plume has its own emission and supersaturation, and the spreading and shearing of each plume's cross-section are calculated as a function of time. Aerosol- and contrail-particle core compositions are tracked for each size and affect optical properties in each plume. When line contrails sublimate/evaporate, their size- and composition-resolved aerosol cores and water vapor are added to the grid scale where they affect large-scale clouds. Algorithm properties are analyzed, and the end-result model is evaluated against in situ and satellite data.

  3. 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.

  4. Exhaust cloud rise and diffusion in the atmosphere

    NASA Technical Reports Server (NTRS)

    Chandler, M. W.; Chu, R. T.; Thayer, S. D.

    1971-01-01

    Analytical approach develops physical-mathematical model of rocket engine exhaust cloud rise, growth, and diffusion. Analytic derivations and resultant model apply to hot exhaust cloud study or industrial stack plumes, making work results applicable to air pollution. Model formulations apply to all exhaust cloud types and various atmospheric conditions.

  5. REAL-TIME AND INTEGRATED MEASUREMENT OF POTENTIAL HUMAN EXPOSURE TO PARTICLE-BOUND POLYCYCLIC AROMATIC HYDROCARBONS (PAHS) FROM AIRCRAFT EXHAUST

    EPA Science Inventory

    Real-time monitors and low-volume air samplers were used to measure the potential human exposure to airborne polycyclic aromatic hydrocarbon (PAH) concentrations during various flight-related and ground-support activities of C-130H aircraft at an Air National Guard base. Three...

  6. Effect of air temperature and relative humidity at various fuel-air ratios on exhaust emissions on a per-mode basis of an Avco Lycoming 0-320 DIAD light aircraft engine. Volume 2: Individual data points

    NASA Technical Reports Server (NTRS)

    Skorobatckyi, M.; Cosgrove, D. V.; Meng, P. R.; Kempke, E. R.

    1976-01-01

    A carbureted four cylinder air cooled 0-320 DIAD Lycoming aircraft engine was tested to establish the effects of air temperature and humidity at various fuel-air ratios on the exhaust emissions on a per-mode basis. The test conditions included carburetor lean-out at air temperatures of 50, 59, 80, and 100 F at relative humidities of 0, 30, 60, and 80 percent. 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. Even at a fixed fuel-air ratio, the HC emissions increase and the NOx emissions decrease at the higher values of air temperature and humidity. Volume II contains the data taken at each of the individual test points.

  7. Effect of Air Temperature and Relative Humidity at Various Fuel-Air Ratios on Exhaust Emissions on a Per-Mode Basis of an AVCO Lycoming 0-320 Diad Light Aircraft Engine: Volume 1: Results and Plotted Data

    NASA Technical Reports Server (NTRS)

    Skorobatckyi, M.; Cosgrove, D. V.; Meng, P. R.; Kempe, E. E., Jr.

    1978-01-01

    A carbureted four cylinder air cooled 0-320 DIAD Lycoming aircraft engine was tested to establish the effects of air temperature and humidity at various fuel-air ratios on the exhaust emissions on a per-mode basis. The test conditions include carburetor lean out at air temperatures of 50, 59, 80, and 100 F at relative humidities of 0, 30, 60, and 80 percent. 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. Even at a fixed fuel air ratio, the HC emissions increase and the NOx emissions decrease at the higher values of air temperature and humidity.

  8. Ice Prevention on Aircraft by Means of Engine Exhaust Heat and a Technical Study of Heat Transmission from a Clark Y Airfoil

    NASA Technical Reports Server (NTRS)

    Theodorsen, Theodore; Clay, William C

    1933-01-01

    This investigation was conducted to study the practicability of employing heat as a means of preventing the formation of ice on airplane wings. The report relates essentially to technical problems regarding the extraction of heat from the exhaust gases and its proper distribution over the exposed surfaces. In this connection a separate study has been made to determine the variation of the coefficient of heat transmission along the chord of a Clark Y airfoil. Experiments on ice prevention both in the laboratory and in flight show conclusively that it is necessary to heat only the front portion of the wing surface to effect complete prevention. Experiments in flight show that a vapor-heating system which extracts heat from the exhaust and distributes it to the wings is an entirely practical and efficient method for preventing ice formation.

  9. Airborne Observations of Aerosol Emissions from F-16 Aircraft

    NASA Technical Reports Server (NTRS)

    Anderson, B. E.; Cofer, W. R.; McDougal, D. S.

    1999-01-01

    We presented results from the SASS Near-Field Interactions Flight (SNIF-III) Experiment which was conducted during May and June 1997 in collaboration with the Vermont and New Jersey Air National Guard Units. The project objectives were to quantify the fraction of fuel sulfur converted to S(VI) species by jet engines and to gain a better understanding of particle formation and growth processes within aircraft wakes. Size and volatility segregated aerosol measurements along with sulfur species measurements were recorded in the exhaust of F-16 aircraft equipped with F-100 engines burning fuels with a range of fuel S concentrations at different altitudes and engine power settings. A total of 10 missions were flown in which F-16 exhaust plumes were sampled by an instrumented T-39 Sabreliner aircraft. On six of the flights, measurements were obtained behind the same two aircraft, one burning standard JP-8 fuel and the other either approximately 28 ppm or 1100 ppm S fuel or an equal mixture of the two (approximately 560 ppm S). A pair of flights was conducted for each fuel mixture, one at 30,000 ft altitude and the other starting at 35,000 ft and climbing to higher altitudes if contrail conditions were not encountered at the initial flight level. In each flight, the F-16s were operated at two power settings, approx. 80% and full military power. Exhaust emissions were sampled behind both aircraft at each flight level, power setting, and fuel S concentration at an initial aircraft separation of 30 m, gradually widening to about 3 km. Analyses of the aerosol data in the cases where fuel S was varied suggest results were consistent with observations from project SUCCESS, i.e., a significant fraction of the fuel S was oxidized to form S(VI) species and volatile particle emission indices (EIs) in comparably aged plumes exhibited a nonlinear dependence upon the fuel S concentration. For the high sulfur fuel, volatile particle EIs in 10-second-old-plumes were 2 to 3 x 10 (exp 17

  10. Particle Size Distributions Measured in the B757 Engine Plume During EXCAVATE

    NASA Technical Reports Server (NTRS)

    Sanders, Terry; Penko, Paul; Rivera, Monica; Culler, Steve

    2005-01-01

    The Experiment to Characterize Aircraft Volatile Aerosols and Trace Species Emissions (EXCAVATE) took place at NASA Langley Research Center during January 2002. This ground based study was conducted to examine the role of fuel sulfur content on particulate emissions. Size distributions as a function of engine operating conditions were measured in the exhaust plume of a B-757 at four downstream axial locations (1 m, 10 m, 25 m and 35 m). The engine was run on JP-5 with three different sulfur concentrations, 810 ppm, 1050 ppm, 1820 ppm; and was operated over a range of power settings from idle to near-full power. Zalabsky differential-mobility analyzers DMAS), Met One condensation-nuclei counters (CNCs), and a TSI 3022 condensation-particle counter (CPC) were used to measure the size distributions. The total number-count (particle concentration), number-based Emissions Index (EInumber) and mass-based Emissions Index (E1-J increased with fuel sulfur-content and engine pressure ratio (EPR). Count Mean Diameter (Ch4D) also increased with EPR yet remained fairly constant with fuel sulfur-content for a fixed location in the exhaust plume. Also the mode and CMD both increased with distance in the plume.

  11. A preliminary assessment of the impact of 2-D exhaust-nozzle geometry on the cruise range of a hypersonic aircraft with top-mounted ramjet propulsion

    NASA Technical Reports Server (NTRS)

    Vahl, W. A.; Weidner, J. P.

    1980-01-01

    A theoretical study of full length and shortened, two dimensional, isentropic, exhaust nozzles integrated with top mounted ramjet propulsion nacelles were conducted. Both symmetric and asymmetric contoured nozzles with a range of angular orientations were considered. Performance comparisons to determine optimum installations for a representative hypersonic vehicle at Mach 5 cruise conditions are presented on the basis of cruise range, propulsive specific impulse, inlet area requirements, and overall lift drag ratio. The effect of approximating the nozzle internal contours with planar surfaces and the determination of viscous and frozen flow effects are also presented.

  12. Light aircraft sound transmission study

    NASA Technical Reports Server (NTRS)

    Atwal, M.; David, J.; Heitman, K.; Crocker, M. J.

    1983-01-01

    The revived interest in the design of propeller driven aircraft is based on increasing fuel prices as well as on the need for bigger short haul and commuter aircraft. A major problem encountered with propeller driven aircraft is propeller and exhaust noise that is transmitted through the fuselage sidewall structure. Part of the work which was conducted during the period April 1 to August 31, 1983, on the studies of sound transmission through light aircraft walls is presented.

  13. The atmospheric effects of stratospheric aircraft: A third program report

    NASA Technical Reports Server (NTRS)

    Stolarski, Richard S. (Editor); Wesoky, Howard L. (Editor)

    1993-01-01

    A third report from the Atmospheric Effects of Stratospheric Aircraft (AESA) component of NASA's High-Speed Research Program (HSRP) is presented. Market and technology considerations continue to provide an impetus for high-speed civil transport research. A recent United Nations Environment Program scientific assessment showed that considerable uncertainty still exists about the possible impact of aircraft on the atmosphere. The AESA was designed to develop the body of scientific knowledge necessary for the evaluation of the impact of stratospheric aircraft on the atmosphere. The first Program report presented the basic objectives and plans for AESA. This third report marks the midpoint of the program and presents the status of the ongoing research on the impact of stratospheric aircraft on the atmosphere as reported at the third annual AESA Program meeting in June 1993. The focus of the program is on predicted atmospheric changes resulting from projected HSCT emissions. Topics reported on cover how high-speed civil transports (HSCT) might affect stratospheric ozone, emissions scenarios and databases to assess potential atmospheric effects from HSCT's, calculated results from 2-D zonal mean models using emissions data, engine trace constituent measurements, and exhaust plume/aircraft wake vortex interactions.

  14. The atmospheric effects of stratospheric aircraft: A third program report

    SciTech Connect

    Stolarski, R.S.; Wesoky, H.L.

    1993-11-01

    A third report from the Atmospheric Effects of Stratospheric Aircraft (AESA) component of NASA's High-Speed Research Program (HSRP) is presented. Market and technology considerations continue to provide an impetus for high-speed civil transport research. A recent United Nations Environment Program scientific assessment showed that considerable uncertainty still exists about the possible impact of aircraft on the atmosphere. The AESA was designed to develop the body of scientific knowledge necessary for the evaluation of the impact of stratospheric aircraft on the atmosphere. The first Program report presented the basic objectives and plans for AESA. This third report marks the midpoint of the program and presents the status of the ongoing research on the impact of stratospheric aircraft on the atmosphere as reported at the third annual AESA Program meeting in June 1993. The focus of the program is on predicted atmospheric changes resulting from projected HSCT emissions. Topics reported on cover how high-speed civil transports (HSCT) might affect stratospheric ozone, emissions scenarios and databases to assess potential atmospheric effects from HSCT's, calculated results from 2-D zonal mean models using emissions data, engine trace constituent measurements, and exhaust plume/aircraft wake vortex interactions. Separate abstracts have been indexed for articles from this report.

  15. OPAD data analysis. [Optical Plumes Anomaly Detection

    NASA Technical Reports Server (NTRS)

    Buntine, Wray L.; Kraft, Richard; Whitaker, Kevin; Cooper, Anita E.; Powers, W. T.; Wallace, Tim L.

    1993-01-01

    Data obtained in the framework of an Optical Plume Anomaly Detection (OPAD) program intended to create a rocket engine health monitor based on spectrometric detections of anomalous atomic and molecular species in the exhaust plume are analyzed. The major results include techniques for handling data noise, methods for registration of spectra to wavelength, and a simple automatic process for estimating the metallic component of a spectrum.

  16. 14 CFR 34.23 - Exhaust Emission Standards for Engines Manufactured on and after July 18, 2012.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT FUEL VENTING AND EXHAUST EMISSION REQUIREMENTS FOR TURBINE ENGINE POWERED AIRPLANES Exhaust Emissions (New Aircraft Gas Turbine Engines) § 34.23 Exhaust Emission... emissions from each new aircraft gas turbine engine shall not exceed: (1) For Classes TF, T3 and T8 of...

  17. 14 CFR 34.23 - Exhaust Emission Standards for Engines Manufactured on and after July 18, 2012.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT FUEL VENTING AND EXHAUST EMISSION REQUIREMENTS FOR TURBINE ENGINE POWERED AIRPLANES Exhaust Emissions (New Aircraft Gas Turbine Engines) § 34.23 Exhaust Emission... emissions from each new aircraft gas turbine engine shall not exceed: (1) For Classes TF, T3 and T8 of...

  18. Direct Measurement of Mercury Reactions In Coal Power Plant Plumes

    SciTech Connect

    Leonard Levin

    2005-12-31

    west of Kenosha. Aircraft and ground measurements support the occurrence of a reduction in the fraction of reactive gaseous mercury (RGM) (with a corresponding increase in elemental mercury) as part of the Total Gaseous Mercury (TGM) emitted from the Pleasant Prairie stack. This occurrence is based on comparison of the RGM concentrations in the plume (at standard conditions) compared to the RGM in the stack. There was found to be a 44% drop in the fraction of RGM between the stack exit and the first sampling arc and a 66% reduction from the stack to the 5-mile sampling arc, with no additional drop between the 5- and 10-mile arcs. Smaller-scale experiments in both test chambers and pilot-scale coal combustor exhaust streams have indicated the presence of rapid and relatively complete reduction reactions converting divalent into elemental mercury within power plant plumes prior to full dispersion in the atmosphere. These measurements, however, have been unable to identify whether the reactions occur during plume rise from physical to virtual stack height (during positive thermal buoyancy). The presence, rate, completeness, ubiquity, and dependence on source characteristics of these reactions, however, must be demonstrated in plume environments associated with fully operational power plants. That requirement, to capture either the reactions or the reaction products of chemistry that may be occurring very close to stack exits in highly turbulent environments, constrains the precision and reproducibility with which such full-scale experiments can be carried out. The work described here is one of several initial steps required to test whether, and in what direction, such rapid mercury redox reactions might be occurring in such plumes.

  19. Modeling of Lightning-Related Plumes into the Chemistry and Transport GEOS-Chem Global Model: Impact on the Upper Tropospheric Chemistry.

    NASA Astrophysics Data System (ADS)

    Gressent, A.

    2014-12-01

    This work is dedicated to the study of the lightning-related plumes in terms of origin, quantification of the plumes trace gas, and impact on the budget of ozone in particular in the upper troposphere (critical region regarding the greenhouse effect). Recently, Gressent et al., 2014, demonstrated that the majority (74%) of large scale plumes (>300km) from lightning emissions (LNOx) is related to warm conveyor belts and extra-tropical cyclones originating from North America and entering the intercontinental pathway between North America and Europe, leading to a negative (positive) west to east NOy (O3) zonal gradient with -0.4 (+18) ppb difference during spring and -0.6 (+14) ppb difference in summer. In order to better constraint lightning emissions impact in global models, a plume parameterization has been implemented in the 3D chemistry and transport GEOS-Chem global model (Harvard University). Such parameterization was successfully developed for aircraft exhausts application (Cariolle et al., 2009). It allows reproducing sub-grid processes related to lightning NOx chemistry and the chemical evolution during transport in the atmosphere. The issue is here based on the evaluation of parameters such as the plume lifetime and the effective reaction rate constant within the plume. The Dynamically Simple Model of Atmospheric Chemical Complexity (DSMACC) is used to determine such critical values and to better understand the chemical interactions between NOx and O3 species within the undiluted fraction of the plume. Additionally high-resolved simulations of the French meso-scale Meso-NH model are applied over specific case studies of thunderstorms in order to consider the dynamical conditions necessary to represent the plume dilution to the background atmosphere. Finally, sensitivity tests are carried out with the GEOS-Chem model to evaluate the impact of this plume-in-grid model on the ozone and nitrogen species budget.

  20. Digital filtering of plume emission spectra

    NASA Technical Reports Server (NTRS)

    Madzsar, George C.

    1990-01-01

    Fourier transformation and digital filtering techniques were used to separate the superpositioned spectral phenomena observed in the exhaust plumes of liquid propellant rocket engines. Space shuttle main engine (SSME) spectral data were used to show that extraction of spectral lines in the spatial frequency domain does not introduce error, and extraction of the background continuum introduces only minimal error. Error introduced during band extraction could not be quantified due to poor spectrometer resolution. Based on the atomic and molecular species found in the SSME plume, it was determined that spectrometer resolution must be 0.03 nm for SSME plume spectral monitoring.

  1. Plume detachment from a magnetic nozzle

    SciTech Connect

    Deline, Christopher A.; Bengtson, Roger D.; Breizman, Boris N.; Tushentsov, Mikhail R.; Jones, Jonathan E.; Chavers, D. Greg; Dobson, Chris C.; Schuettpelz, Branwen M.

    2009-03-15

    High-powered electric propulsion thrusters utilizing a magnetized plasma require that plasma exhaust detach from the applied magnetic field in order to produce thrust. This paper presents experimental results demonstrating that a sufficiently energetic and flowing plasma can indeed detach from a magnetic nozzle. Microwave interferometer and probe measurements provide plume density, electron temperature, and ion flux measurements in the nozzle region. Measurements of ion flux show a low-beta plasma plume which follows applied magnetic field lines until the plasma kinetic pressure reaches the magnetic pressure and a high-beta plume expanding ballistically afterward. Several magnetic configurations were tested including a reversed field nozzle configuration. Despite the dramatic change in magnetic field profile, the reversed field configuration yielded little measurable change in plume trajectory, demonstrating the plume is detached. Numerical simulations yield density profiles in agreement with the experimental results.

  2. Analysis of stratified and closely spaced jets exhausting into a crossflow. [aerodynamic characteristics of lift-jet, vectored thrust, and lift fan V/STOL aircraft

    NASA Technical Reports Server (NTRS)

    Ziegler, H.; Woller, P. T.

    1973-01-01

    Procedures have been developed for determining the flow field about jets with velocity stratification exhausting into a crossflow. Jets with three different types of exit velocity stratification have been considered: (1) jets with a relatively high velocity core; (2) jets with a relatively low velocity core; and (3) jets originating from a vaned nozzle. The procedure developed for a jet originating from a high velocity core nozzle is to construct an equivalent nozzle having the same mass flow and thrust but having a uniform exit velocity profile. Calculations of the jet centerline and induced surface static pressures have been shown to be in good agreement with test data for a high velocity core nozzle. The equivalent ideal nozzle has also been shown to be a good representation for jets with a relatively low velocity core and for jets originating from a vaned nozzle in evaluating jet-induced flow fields. For the singular case of a low velocity core nozzle, namely a nozzle with a dead air core, and for the vaned nozzle, an alternative procedure has been developed. The internal mixing which takes place in the jet core has been properly accounted for in the equations of motion governing the jet development. Calculations of jet centerlines and induced surface static pressures show good agreement with test data these nozzles.

  3. 40 CFR 87.21 - Standards for exhaust emissions.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 21 2012-07-01 2012-07-01 false Standards for exhaust emissions. 87.21 Section 87.21 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) Definitions. Exhaust Emissions (New Aircraft Gas Turbine Engines) § 87.21 Standards for exhaust emissions. Link to an amendment published...

  4. Electrically charged small soot particles in the exhaust of an aircraft gas-turbine engine combustor: comparison of model and experiment

    NASA Astrophysics Data System (ADS)

    Sorokin, A.; Arnold, F.

    The emission of electrically charged soot particles by an aircraft gas-turbine combustor is investigated using a theoretical model. Particular emphasis is placed on the influence of the fuel sulfur content (FSC). The model considers the production of primary "combustion" electrons and ions in the flame zone and their following interaction with molecular oxygen, sulfur-bearing molecules (e.g. O 2, SO 2, SO 3, etc.) and soot particles. The soot particle size distribution is approximated by two different populations of mono-dispersed large and small soot particles with diameters of 20-30 and 5-7 nm, respectively. The effect of thermal ionization of soot and its interaction with electrons and positive and negative ions is included in the model. The computed positive and negative chemiion (CI) concentrations at the combustor exit and relative fractions of small neutral and charged soot particles were found to be in satisfactory agreement with experimental data. The results show that the FSC indeed may influence the concentration of negative CI at low fuel flow into combustor. Importantly the simulation indicates a very efficient mutual interaction of electrons and ions with soot particles with a large effect on both ion and charged soot particle concentrations. This result may be interpreted as a possible indirect effect of FSC on the growth and size distribution of soot particles.

  5. 40 CFR Appendix Vi to Part 266 - Stack Plume Rise

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 28 2012-07-01 2012-07-01 false Stack Plume Rise VI Appendix VI to Part 266 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) SOLID WASTES (CONTINUED... FACILITIES Pt. 266, App. VI Appendix VI to Part 266—Stack Plume Rise Flow rate (m3/s) Exhaust Temperature...

  6. 40 CFR Appendix Vi to Part 266 - Stack Plume Rise

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 27 2014-07-01 2014-07-01 false Stack Plume Rise VI Appendix VI to Part 266 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) SOLID WASTES (CONTINUED... FACILITIES Pt. 266, App. VI Appendix VI to Part 266—Stack Plume Rise Flow rate (m3/s) Exhaust Temperature...

  7. 40 CFR Appendix Vi to Part 266 - Stack Plume Rise

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 26 2010-07-01 2010-07-01 false Stack Plume Rise VI Appendix VI to Part 266 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) SOLID WASTES (CONTINUED... FACILITIES Pt. 266, App. VI Appendix VI to Part 266—Stack Plume Rise Flow rate (m3/s) Exhaust Temperature...

  8. 40 CFR Appendix Vi to Part 266 - Stack Plume Rise

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 27 2011-07-01 2011-07-01 false Stack Plume Rise VI Appendix VI to Part 266 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) SOLID WASTES (CONTINUED... FACILITIES Pt. 266, App. VI Appendix VI to Part 266—Stack Plume Rise Flow rate (m3/s) Exhaust Temperature...

  9. 40 CFR Appendix Vi to Part 266 - Stack Plume Rise

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 28 2013-07-01 2013-07-01 false Stack Plume Rise VI Appendix VI to Part 266 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) SOLID WASTES (CONTINUED... FACILITIES Pt. 266, App. VI Appendix VI to Part 266—Stack Plume Rise Flow rate (m3/s) Exhaust Temperature...

  10. Modeling the formation and properties of traditional and non-traditional secondary organic aerosol: problem formulation and application to aircraft exhaust

    NASA Astrophysics Data System (ADS)

    Jathar, S. H.; Miracolo, M. A.; Presto, A. A.; Adams, P. J.; Robinson, A. L.

    2012-04-01

    We present a methodology to model secondary organic aerosol (SOA) formation from the photo-oxidation of low-volatility organics (semi-volatile and intermediate volatility organic compounds). The model is parameterized and tested using SOA data collected during two field campaigns that characterized the atmospheric evolution of dilute gas-turbine engine emissions using a smog chamber. Photo-oxidation formed a significant amount of SOA, much of which cannot be explained based on the emissions of traditional, speciated precursors; we refer to this as non-traditional SOA (NT-SOA). The NT-SOA can be explained by emissions of low-volatility organic vapors measured using sorbents. Since these vapors could not be speciated, we employ a volatility-based approach to model NT-SOA formation. We show that the method proposed by Robinson et al. (2007) is unable to explain the timing of NT-SOA formation because it assumes a very modest reduction in volatility of the precursors with every oxidation reaction. In contrast, a Hybrid method, similar to models of traditional SOA formation, assumes a larger reduction in volatility with each oxidation step and results in a better reproduction of NT-SOA formation. The NT-SOA yields estimated for the low-volatility organic vapor emissions are similar to literature data for large n-alkanes and other low-volatility organics. The yields vary with fuel composition (JP8 versus Fischer-Tropsch) and engine load (idle versus non-idle). These differences are consistent with the expected contribution of high (aromatics and n-alkanes) and low (branched alkanes and oxygenated species) SOA forming species to the exhaust.

  11. Crater Formation Due to Lunar Plume Impingement

    NASA Technical Reports Server (NTRS)

    Marsell, Brandon

    2011-01-01

    Thruster plume impingement on a surface comprised of small, loose particles may cause blast ejecta to be spread over a large area and possibly cause damage to the vehicle. For this reason it is important to study the effects of plume impingement and crater formation on surfaces like those found on the moon. Lunar soil, also known as regolith, is made up of fine granular particles on the order of 100 microns.i Whenever a vehicle lifts-off from such a surface, the exhaust plume from the main engine will cause the formation of a crater. This crater formation may cause laterally ejected mass to be deflected and possibly damage the vehicle. This study is a first attempt at analyzing the dynamics of crater formation due to thruster exhaust plume impingement during liftoff from the moon. Though soil erosion on the lunar surface is not considered, this study aims at examining the evolution of the shear stress along the lunar surface as the engine fires. The location of the regions of high shear stress will determine where the crater begins to form and will lend insight into how big the crater will be. This information will help determine the probability that something will strike the vehicle. The final sections of this report discuss a novel method for studying this problem that uses a volume of fluid (VOF)ii method to track the movement of both the exhaust plume and the eroding surface.

  12. The Milan photooxidant plume

    NASA Astrophysics Data System (ADS)

    PréVôT, André S. H.; Staehelin, Johannes; Kok, Gregory L.; Schillawski, Richard D.; Neininger, Bruno; Staffelbach, Thomas; Neftel, Albrecht; Wernli, Heini; Dommen, Josef

    1997-10-01

    In Switzerland, measurement campaigns including aircraft measurements were carried out in the summers of 1992 and 1993 as part of the Pollution and Meteorology (POLLUMET) study. Ozone (O3) concentrations, up to 185 ppb, with a large spatial variability were found south of the Alps in the afternoon. Comparison to measurements north of the Alps shows that these concentration levels are extraordinarily high for central Europe. Backward trajectories reveal that the highest O3 levels were found 4-5 hours downwind of Milan, Italy. The measurements suggest a reactive organic gas (ROG) sensitive O3 production regime 1-3 hours downwind in the plume, and a NOx (sum of nitrogen oxide (NO) and nitrogen dioxide (NO2)) limitation in air masses not affected by the Milan plume. Air masses originating north of Milan are probably close to the transition zone between the two photochemical regimes. This was found by using measurements of total odd nitrogen (NOy,), NO, NO2, formaldehyde (HCHO), and hydrogen peroxide (H2O2) yielding indicators for ROG and NOx sensitive O3 production. The slope of ozone versus NOz (=NOy-NOx: photochemical products of NOx) were markedly higher in NOx limited conditions (ΔO3/ΔNOz=13.6) than in air masses close to the transition zone (ΔO3/ΔNOz=4.2).

  13. PHYSICAL AND NUMERICAL MODELING OF ASD EXHAUST DISPERSION AROUND HOUSES

    EPA Science Inventory

    The report discusses the use of a wind tunnel to physically model the dispersion of exhaust plumes from active soil depressurization (ASD) radon mitigation systems in houses. he testing studied the effects of exhaust location (grade level vs. above the eave), as house height, roo...

  14. Magnetic Detachment and Plume Control in Escaping Magnetized Plasma

    SciTech Connect

    P. F. Schmit and N. J. Fisch

    2008-11-05

    The model of two-fluid, axisymmetric, ambipolar magnetized plasma detachment from thruster guide fields is extended to include plasmas with non-zero injection angular velocity profiles. Certain plasma injection angular velocity profiles are shown to narrow the plasma plume, thereby increasing exhaust efficiency. As an example, we consider a magnetic guide field arising from a simple current ring and demonstrate plasma injection schemes that more than double the fraction of useful exhaust aperture area, more than halve the exhaust plume angle, and enhance magnetized plasma detachment.

  15. 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.

  16. Compact high-speed MWIR spectrometer applied to monitor CO2 exhaust dynamics from a turbojet engine

    NASA Astrophysics Data System (ADS)

    Linares-Herrero, R.; Vergara, G.; Gutiérrez Álvarez, R.; Fernández Montojo, C.; Gómez, L. J.; Villamayor, V.; Baldasano Ramírez, A.; Montojo, M. T.; Archilla, V.; Jiménez, A.; Mercader, D.; González, A.; Entero, A.

    2013-05-01

    Dfgfdg Due to international environmental regulations, aircraft turbojet manufacturers are required to analyze the gases exhausted during engine operation (CO, CO2, NOx, particles, unburned hydrocarbons (aka UHC), among others).Standard procedures, which involve sampling the gases from the exhaust plume and the analysis of the emissions, are usually complex and expensive, making a real need for techniques that allow a more frequent and reliable emissions measurements, and a desire to move from the traditional gas sampling-based methods to real time and non-intrusive gas exhaust analysis, usually spectroscopic. It is expected that the development of more precise and faster optical methods will provide better solutions in terms of performance/cost ratio. In this work the analysis of high-speed infrared emission spectroscopy measurements of plume exhaust are presented. The data was collected during the test trials of commercial engines carried out at Turbojet Testing Center-INTA. The results demonstrate the reliability of the technique for studying and monitoring the dynamics of the exhausted CO2 by the observation of the infrared emission of hot gases. A compact (no moving parts), high-speed, uncooled MWIR spectrometer was used for the data collection. This device is capable to register more than 5000 spectra per second in the infrared band ranging between 3.0 and 4.6 microns. Each spectrum is comprised by 128 spectral subbands with aband width of 60 nm. The spectrometer operated in a passive stand-off mode and the results from the measurements provided information of both the dynamics and the concentration of the CO2 during engine operation.

  17. Analysis of Plume Effects on Sonic Boom Signature for Isolated Nozzle Configurations

    NASA Technical Reports Server (NTRS)

    Castner, Raymond S.

    2008-01-01

    Computational fluid dynamics (CFD) analysis has been performed to study the plume effects on sonic boom signature for isolated nozzle configurations. The objectives of these analyses were to provide comparison to past work using modern CFD analysis tools, to investigate the differences of high aspect ratio nozzles to circular (axisymmetric) nozzles, and to report the effects of underexpanded nozzle operation on boom signature. CFD analysis was used to address the plume effects on sonic boom signature from a baseline exhaust nozzle. Near-field pressure signatures were collected for nozzle pressure ratios (NPRs) between 6 and 10. A computer code was used to extrapolate these signatures to a ground-observed sonic boom N-wave. Trends show that there is a reduction in sonic boom N-wave signature as NPR is increased from 6 to 10. The performance curve for this supersonic nozzle is flat, so there is not a significant loss in thrust coefficient as the NPR is increased. As a result, this benefit could be realized without significant loss of performance. Analyses were also collected for a high aspect ratio nozzle based on the baseline design for comparison. Pressure signatures were collected for nozzle pressure ratios from 8 to 12. Signatures were nearly twice as strong for the two-dimensional case, and trends also show a reduction in sonic boom signature as NPR is increased from 8 to 12. As low boom designs are developed and improved, there will be a need for understanding the interaction between the aircraft boat tail shocks and the exhaust nozzle plume. These CFD analyses will provide a baseline study for future analysis efforts.

  18. Dust Plumes off Libya

    NASA Technical Reports Server (NTRS)

    2007-01-01

    Two-toned dust plumes blew northward off the coast of Libya on October 26, 2007, as the Moderate Resolution Imaging Spectroradiometer (MODIS) on NASA's Terra satellite took this picture. While plumes in the west are beige, reminiscent of the Sahara's sands, the plumes in the east are distinctly darker. The differences in color can be traced to the plumes's varied origins.

  19. Volcanic Plume Chemistry: Models, Observations and Impacts

    NASA Astrophysics Data System (ADS)

    Roberts, Tjarda; Martin, Robert; Oppenheimer, Clive; Griffiths, Paul; Braban, Christine; Cox, Tony; Jones, Rod; Durant, Adam; Kelly, Peter

    2010-05-01

    mercury. Excitingly, we can now begin to compare the model simulations to very recently reported in-situ aircraft and balloon measurements in downwind volcanic plumes, which found e.g. ozone depletion at Redoubt, ozone depletion and elevated HNO3 at Erebus and sulfate-H2O interactions at Kilauea. Satellite observations of volcanic BrO, and DOAS observations of BrO under varying plume conditions have also recently been reported. Such comparisons may highlight additional chemistry (e.g. HO2NO2 at Erebus), identify further underlying processes (e.g. the role of plume dispersion and gas fluxes in controlling plume chemistry), guide future field-observation strategies, and support and improve the model simulations that aim to understand volcanic emissions, plume chemistry, and predict the environmental impacts of volcanic plumes.

  20. Exhaust emission control apparatus

    SciTech Connect

    Eng, J.W.

    1991-09-24

    This patent describes an exhaust control apparatus for muffling noise and treating odors and pollutants, including solid particulate and gases in the exhaust of an internal combustion engine. It comprises an exhaust inlet tube for receiving the exhaust generated by an internal combustion engine; a cyclone barrier concentrically surrounding the exhaust inlet tube, a ring cavity between the cyclone tube and exhaust inlet tube defining a cyclone chamber in which the exhaust is treated; means for directing the exhaust from the exhaust inlet tube into the cyclone chamber; electrode means having small openings through which the exhaust passes to enter the cyclone chamber, the electrode means generating electrostatic forces which charge the solid particulate in the exhaust, ionize air and generate ozone in the cyclone chamber near the electrode; means for injecting air into the cyclone chamber causing centrifugal flow of the air and the exhausted within the cyclone chamber and increasing a dwell time of the exhaust within the cyclone chamber.

  1. 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. PMID:23618073

  2. D-558-2 Aircraft on lakebed

    NASA Technical Reports Server (NTRS)

    1955-01-01

    longitudinal (pitch) motions; wing and tail loads, lift, drag, and buffeting characteristics of swept-wing aircraft at transonic and supersonic speeds; and the effects of the rocket exhaust plume on lateral dynamic stability throughout the speed range. (Plume effects were a new experience for aircraft.) The number three aircraft also gathered information about the effects of external stores (bomb shapes, drop tanks) upon the aircraft's behavior in the transonic region (roughly 0.7 to 1.3 times the speed of sound). In correlation with data from other early transonic research aircraft such as the XF-92A, this information contributed to solutions to the pitch-up problem in swept-wing aircraft. The three airplanes flew a total of 313 times--123 by the number one aircraft (Bureau No. 37973--NACA 143), 103 by the second Skyrocket (Bureau No. 37974--NACA 144), and 87 by airplane number three (Bureau No. 37975--NACA 145). Skyrocket 143 flew all but one of its missions as part of the Douglas contractor program to test the airplane's performance. NACA aircraft 143 was initially powered by a Westinghouse J-34-40 turbojet engine configured only for ground take-offs, but in 1954-55 the contractor modified it to an all-rocket air-launch capability featuring an LR8-RM-6, 4-chamber Reaction Motors engine rated at 6,000 pounds of thrust at sea level (the Navy designation for the Air Force's LR-11 used in the X-1). In this configuration, NACA research pilot John McKay flew the airplane only once for familiarization on September 17, 1956. The 123 flights of NACA 143 served to validate wind-tunnel predictions of the airplane's performance, except for the fact that the airplane experienced less drag above Mach 0.85 than the wind tunnels had indicated. NACA 144 also began its flight program with a turbojet powerplant. NACA pilots Robert A. Champine and John H. Griffith flew 21 times in this configuration to test airspeed calibrations and to research longitudinal and lateral stability and control

  3. Space shuttle exhaust cloud properties

    NASA Technical Reports Server (NTRS)

    Anderson, B. J.; Keller, V. W.

    1983-01-01

    A data base describing the properties of the exhaust cloud produced by the launch of the Space Transportation System and the acidic fallout observed after each of the first four launches was assembled from a series of ground and aircraft based measurements made during the launches of STS 2, 3, and 4. Additional data were obtained from ground-based measurements during firings of the 6.4 percent model of the Solid Rocket Booster at the Marshall Center. Analysis indicates that the acidic fallout is produced by atomization of the deluge water spray by the rocket exhaust on the pad followed by rapid scavening of hydrogen chloride gas aluminum oxide particles from the Solid Rocket Boosters. The atomized spray is carried aloft by updrafts created by the hot exhaust and deposited down wind. Aircraft measurements in the STS-3 ground cloud showed an insignificant number of ice nuclei. Although no measurements were made in the column cloud, the possibility of inadvertent weather modification caused by the interaction of ice nuclei with natural clouds appears remote.

  4. 14 CFR 25.1123 - Exhaust piping.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 14 Aeronautics and Space 1 2012-01-01 2012-01-01 false Exhaust piping. 25.1123 Section 25.1123 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT AIRWORTHINESS... corrosion resistant, and must have provisions to prevent failure due to expansion by operating...

  5. 14 CFR 27.1123 - Exhaust piping.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 14 Aeronautics and Space 1 2013-01-01 2013-01-01 false Exhaust piping. 27.1123 Section 27.1123 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT AIRWORTHINESS... must be heat and corrosion resistant, and must have provisions to prevent failure due to expansion...

  6. 14 CFR 29.1123 - Exhaust piping.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 14 Aeronautics and Space 1 2013-01-01 2013-01-01 false Exhaust piping. 29.1123 Section 29.1123 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT AIRWORTHINESS... piping must be heat and corrosion resistant, and must have provisions to prevent failure due to...

  7. 14 CFR 27.1123 - Exhaust piping.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 14 Aeronautics and Space 1 2012-01-01 2012-01-01 false Exhaust piping. 27.1123 Section 27.1123 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT AIRWORTHINESS... must be heat and corrosion resistant, and must have provisions to prevent failure due to expansion...

  8. 14 CFR 27.1123 - Exhaust piping.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 14 Aeronautics and Space 1 2014-01-01 2014-01-01 false Exhaust piping. 27.1123 Section 27.1123 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT AIRWORTHINESS... must be heat and corrosion resistant, and must have provisions to prevent failure due to expansion...

  9. 14 CFR 25.1123 - Exhaust piping.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 14 Aeronautics and Space 1 2013-01-01 2013-01-01 false Exhaust piping. 25.1123 Section 25.1123 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT AIRWORTHINESS... corrosion resistant, and must have provisions to prevent failure due to expansion by operating...

  10. 14 CFR 25.1123 - Exhaust piping.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 14 Aeronautics and Space 1 2011-01-01 2011-01-01 false Exhaust piping. 25.1123 Section 25.1123 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT AIRWORTHINESS... corrosion resistant, and must have provisions to prevent failure due to expansion by operating...

  11. 14 CFR 25.1123 - Exhaust piping.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 14 Aeronautics and Space 1 2014-01-01 2014-01-01 false Exhaust piping. 25.1123 Section 25.1123 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT AIRWORTHINESS... corrosion resistant, and must have provisions to prevent failure due to expansion by operating...

  12. 14 CFR 27.1123 - Exhaust piping.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 14 Aeronautics and Space 1 2011-01-01 2011-01-01 false Exhaust piping. 27.1123 Section 27.1123 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT AIRWORTHINESS... must be heat and corrosion resistant, and must have provisions to prevent failure due to expansion...

  13. 14 CFR 29.1123 - Exhaust piping.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 14 Aeronautics and Space 1 2012-01-01 2012-01-01 false Exhaust piping. 29.1123 Section 29.1123 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT AIRWORTHINESS... piping must be heat and corrosion resistant, and must have provisions to prevent failure due to...

  14. 14 CFR 29.1123 - Exhaust piping.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 14 Aeronautics and Space 1 2014-01-01 2014-01-01 false Exhaust piping. 29.1123 Section 29.1123 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT AIRWORTHINESS... piping must be heat and corrosion resistant, and must have provisions to prevent failure due to...

  15. 14 CFR 29.1123 - Exhaust piping.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 14 Aeronautics and Space 1 2011-01-01 2011-01-01 false Exhaust piping. 29.1123 Section 29.1123 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT AIRWORTHINESS... piping must be heat and corrosion resistant, and must have provisions to prevent failure due to...

  16. Studies of aircraft wake chemistry and dispersion

    NASA Technical Reports Server (NTRS)

    Poppoff, I. G.; Farlow, N. H.; Anderson, L. B.

    1974-01-01

    Use of aerospace technology to study aircraft wakes is reviewed. It is shown how aerospace vehicles can be used to provide data for increased understanding of the atmosphere and of aircraft exhaust trails where knowledge is inadequate to evaluate fully the potential impact of the engine emissions. Models of aircraft near-field exhaust wakes are characterized by jet, vortex, and dispersion regimes. Wake growth in the jet regime is self-determined and rapid, whereas further spreading is inhibited in the vortex regime because of circulating vortex motion. Wake diffusion in the dispersion regime is initially influenced by aircraft induced turbulence but is dominated later by small-scale atmospheric turbulence. Computed fluid mechanical results show the importance of effects such as wake buoyancy, wind shear, turbulence, and traffic corridor exhaust buildup on dispersion of the wake. In the jet regime the exhaust characteristics and thermochemistry serve to illustrate initial chemical changes involving potential pollutant species.

  17. D-558-2 Aircraft on lakebed

    NASA Technical Reports Server (NTRS)

    1954-01-01

    gathered a great deal of data about pitch-up and the coupling of lateral (yaw) and longitudinal (pitch) motions; wing and tail loads, lift, drag, and buffeting characteristics of swept-wing aircraft at transonic and supersonic speeds; and the effects of the rocket exhaust plume on lateral dynamic stability throughout the speed range. (Plume effects were a new experience for aircraft.) The number three aircraft also gathered information about the effects of external stores (bomb shapes, drop tanks) upon the aircraft's behavior in the transonic region (roughly 0.7 to 1.3 times the speed of sound). In correlation with data from other early transonic research aircraft such as the XF-92A, this information contributed to solutions to the pitch-up problem in swept-wing aircraft. The three airplanes flew a total of 313 times--123 by the number one aircraft (Bureau No. 37973--NACA 143), 103 by the second Skyrocket (Bureau No. 37974--NACA 144), and 87 by airplane number three (Bureau No. 37975--NACA 145). Skyrocket 143 flew all but one of its missions as part of the Douglas contractor program to test the airplane's performance. NACA aircraft 143 was initially powered by a Westinghouse J-34-40 turbojet engine configured only for ground take-offs, but in 1954-55 the contractor modified it to an all-rocket air-launch capability featuring an LR8-RM-6, 4-chamber Reaction Motors engine rated at 6,000 pounds of thrust at sea level (the Navy designation for the Air Force's LR-11 used in the X-1). In this configuration, NACA research pilot John McKay flew the airplane only once for familiarization on September 17, 1956. The 123 flights of NACA 143 served to validate wind-tunnel predictions of the airplane's performance, except for the fact that the airplane experienced less drag above Mach 0.85 than the wind tunnels had indicated. NACA 144 also began its flight program with a turbojet powerplant. NACA pilots Robert A. Champine and John H. Griffith flew 21 times in this configuration to test

  18. Gas and Particulate Aircraft Emissions Measurements: Impacts on local air quality.

    NASA Astrophysics Data System (ADS)

    Jayne, J. T.; Onasch, T.; Northway, M.; Canagaratna, M.; Worsnop, D.; Timko, M.; Wood, E.; Miake-Lye, R.; Herndon, S.; Knighton, B.; Whitefield, P.; Hagen, D.; Lobo, P.; Anderson, B.

    2007-12-01

    Air travel and freight shipping by air are becoming increasingly important and are expected to continue to expand. The resulting increases in the local concentrations of pollutants, including particulate matter (PM), volatile organic compounds (VOCs), and nitrogen oxides (NOX), can have negative impacts on regional air quality, human health and can impact climate change. In order to construct valid emission inventories, accurate measurements of aircraft emissions are needed. These measurements must be done both at the engine exit plane (certification) and downwind following the rapid cooling, dilution and initial atmospheric processing of the exhaust plume. We present here results from multiple field experiments which include the Experiment to Characterize Volatile Aerosol and Trace Species Emissions (EXCAVATE) and the four Aircraft Particle Emissions eXperiments (APEX- 1/Atlanta/2/3) which characterized gas and particle emissions from both stationary or in-use aircraft. Emission indices (EIs) for NOx and VOCs and for particle number concentration, refractory PM (black carbon soot) and volatile PM (primarily sulfate and organic) particles are reported. Measurements were made at the engine exit plane and at several downstream locations (10 and 30 meters) for a number of different engine types and engine thrust settings. A significant fraction of organic particle mass is composed of low volatility oil-related compounds and is not combustion related, potentially emitted by vents or heated surfaces within aircraft engines. Advected plumes measurements from in-use aircraft show that the practice of reduced thrust take-offs has a significant effect on total NOx and soot emitted in the vicinity of the airport. The measurements reported here represent a first observation of this effect and new insights have been gained with respect to the chemical processing of gases and particulates important to the urban airshed.

  19. Plume Mitigation: Soil Erosion and Lunar Prospecting Sensor Project

    NASA Technical Reports Server (NTRS)

    Metzger, Philip T.

    2014-01-01

    Demonstrate feasibility of the simplest, lowest-mass method of measuring density of a cloud of lunar soil ejected by rocket exhaust, using new math techniques with a small baseline laser/camera system. Focus is on exploring the erosion process that occurs when the exhaust plume of a lunar rocket impacts the regolith. Also, predicting the behavior of the lunar soil that would be blasted from a lunar landing/launch site shall assist in better design and protection of any future lunar settlement from scouring of structures and equipment. NASA is gathering experimental data to improve soil erosion models and understand how lunar particles enter the plume flow.

  20. Imaging Fourier transform spectrometry of chemical plumes

    NASA Astrophysics Data System (ADS)

    Bradley, Kenneth C.; Gross, Kevin C.; Perram, Glen P.

    2009-05-01

    A midwave infrared (MWIR) imaging Fourier transform spectrometer (FTS), the Telops FIRST-MWE (Field-portable Imaging Radiometric Spectrometer Technology - Midwave Extended) has been utilized for the standoff detection and characterization of chemical plumes. Successful collection and analysis of MWIR hyperspectral imagery of jet engine exhaust has allowed us to produce spatial profiles of both temperature and chemical constituent concentrations of exhaust plumes. Successful characterization of this high temperature combustion event has led to the collection and analysis of hyperspectral imagery of lower temperature emissions from industrial smokestacks. This paper presents MWIR data from remote collection of hyperspectral imagery of methyl salicilate (MeS), a chemical warfare agent simulant, during the Chemical Biological Distributed Early Warning System (CBDEWS) test at Dugway Proving Grounds, UT in 2008. The data did not contain spectral lines associated with emission of MeS. However, a few broad spectral features were present in the background-subtracted plume spectra. Further analysis will be required to assign these features, and determine the utility of MWIR hyperspectral imagery for analysis of chemical warfare agent plumes.

  1. Rocket Engine Plume Diagnostics at Stennis Space Center

    NASA Technical Reports Server (NTRS)

    Tejwani, Gopal D.; Langford, Lester A.; VanDyke, David B.; McVay, Gregory P.; Thurman, Charles C.

    2003-01-01

    The Stennis Space Center has been at the forefront of development and application of exhaust plume spectroscopy to rocket engine health monitoring since 1989. Various spectroscopic techniques, such as emission, absorption, FTIR, LIF, and CARS, have been considered for application at the engine test stands. By far the most successful technology h a been exhaust plume emission spectroscopy. In particular, its application to the Space Shuttle Main Engine (SSME) ground test health monitoring has been invaluable in various engine testing and development activities at SSC since 1989. On several occasions, plume diagnostic methods have successfully detected a problem with one or more components of an engine long before any other sensor indicated a problem. More often, they provide corroboration for a failure mode, if any occurred during an engine test. This paper gives a brief overview of our instrumentation and computational systems for rocket engine plume diagnostics at SSC. Some examples of successful application of exhaust plume spectroscopy (emission as well as absorption) to the SSME testing are presented. Our on-going plume diagnostics technology development projects and future requirements are discussed.

  2. Composite hardbody and missile plume (CHAMP 98) IR scene generation program

    NASA Astrophysics Data System (ADS)

    Crow, Dennis R.; Coker, Charles F.

    1998-07-01

    The Composite Hardbody and Missile Plume (CHAMP) program is a computer simulation used to provide time dependent high- fidelity infrared (IR) simulations of airborne vehicles. CHAMP computational algorithms are based on first principle physics that compute hardbody and exhaust plume radiation (absorption, emission, and reflection) for arbitrary vehicle operational state, position, orientation and atmospheric condition. All computations are performed as a function of time to allow complex vehicle dynamics to be simulated. Image processing functions are included to generate anti-aliased focal plane imagery. CHAMP can be utilized to simulate post-boost vehicle, re-entry vehicle, boost missile, theater missile, cruise missile, aircraft, and helicopter applications. CHAMP development is sponsored by the Kinetic Kill Vehicle Hardware- In-the-Loop Simulator (KHILS) facility at Eglin AFB, Florida. CHAMP is routinely utilized by KHILS to support on-going hardware-in-the-loop testing of IR seekers. Many of these tests are complex and diversified. CHAMP has been structured to support these tests by employing current generation object oriented design methodologies that facilitate adaptation to specific test requirements.

  3. CFD Analysis of Nozzle Jet Plume Effects on Sonic Boom Signature

    NASA Technical Reports Server (NTRS)

    Bui, Trong T.

    2009-01-01

    An axisymmetric full Navier-Stokes computational fluid dynamics study is conducted to examine nozzle exhaust jet plume effects on the sonic boom signature of a supersonic aircraft. A simplified axisymmetric nozzle geometry, representative of the nozzle on the NASA Dryden NF-15B Lift and Nozzle Change Effects on Tail Shock research airplane, is considered. The computational fluid dynamics code is validated using available wind-tunnel sonic boom experimental data. The effects of grid size, spatial order of accuracy, grid type, and flow viscosity on the accuracy of the predicted sonic boom pressure signature are quantified. Grid lines parallel to the Mach wave direction are found to give the best results. Second-order accurate upwind methods are required as a minimum for accurate sonic boom simulations. The highly underexpanded nozzle flow is found to provide significantly more reduction in the tail shock strength in the sonic boom N-wave pressure signature than perfectly expanded and overexpanded nozzle flows. A tail shock train in the sonic boom signature is observed for the highly underexpanded nozzle flow. Axisymmetric computational fluid dynamics simulations show the flow physics inside the F-15 nozzle to be nonisentropic and complex. Although the one-dimensional isentropic nozzle plume results look reasonable, they fail to capture the sonic boom shock train in the highly underexpanded nozzle flow.

  4. Simulation of wake vortex radiometric detection via jet exhaust proxy

    NASA Astrophysics Data System (ADS)

    Daniels, Taumi S.

    2015-06-01

    This paper describes an analysis of the potential of an airborne hyperspectral imaging IR instrument to infer wake vortices via turbine jet exhaust as a proxy. The goal was to determine the requirements for an imaging spectrometer or radiometer to effectively detect the exhaust plume, and by inference, the location of the wake vortices. The effort examines the gas spectroscopy of the various major constituents of turbine jet exhaust and their contributions to the modeled detectable radiance. Initially, a theoretical analysis of wake vortex proxy detection by thermal radiation was realized in a series of simulations. The first stage used the SLAB plume model to simulate turbine jet exhaust plume characteristics, including exhaust gas transport dynamics and concentrations. The second stage used these plume characteristics as input to the Line By Line Radiative Transfer Model (LBLRTM) to simulate responses from both an imaging IR hyperspectral spectrometer or radiometer. These numerical simulations generated thermal imagery that was compared with previously reported wake vortex temperature data. This research is a continuation of an effort to specify the requirements for an imaging IR spectrometer or radiometer to make wake vortex measurements. Results of the two-stage simulation will be reported, including instrument specifications for wake vortex thermal detection. These results will be compared with previously reported results for IR imaging spectrometer performance.

  5. Simulation of Wake Vortex Radiometric Detection via Jet Exhaust Proxy

    NASA Technical Reports Server (NTRS)

    Daniels, Taumi S.

    2015-01-01

    This paper describes an analysis of the potential of an airborne hyperspectral imaging IR instrument to infer wake vortices via turbine jet exhaust as a proxy. The goal was to determine the requirements for an imaging spectrometer or radiometer to effectively detect the exhaust plume, and by inference, the location of the wake vortices. The effort examines the gas spectroscopy of the various major constituents of turbine jet exhaust and their contributions to the modeled detectable radiance. Initially, a theoretical analysis of wake vortex proxy detection by thermal radiation was realized in a series of simulations. The first stage used the SLAB plume model to simulate turbine jet exhaust plume characteristics, including exhaust gas transport dynamics and concentrations. The second stage used these plume characteristics as input to the Line By Line Radiative Transfer Model (LBLRTM) to simulate responses from both an imaging IR hyperspectral spectrometer or radiometer. These numerical simulations generated thermal imagery that was compared with previously reported wake vortex temperature data. This research is a continuation of an effort to specify the requirements for an imaging IR spectrometer or radiometer to make wake vortex measurements. Results of the two-stage simulation will be reported, including instrument specifications for wake vortex thermal detection. These results will be compared with previously reported results for IR imaging spectrometer performance.

  6. Impacts of alternative fuels in aviation on microphysical aerosol properties and predicted ice nuclei concentration at aircraft cruise altitude

    NASA Astrophysics Data System (ADS)

    Weinzierl, B.; D'Ascoli, E.; Sauer, D. N.; Kim, J.; Scheibe, M.; Schlager, H.; Moore, R.; Anderson, B. E.; Ullrich, R.; Mohler, O.; Hoose, C.

    2015-12-01

    In the past decades air traffic has been substantially growing affecting air quality and climate. According to the International Civil Aviation Authority (ICAO), in the next few years world passenger and freight traffic is expected to increase annually by 6-7% and 4-5%, respectively. One possibility to reduce aviation impacts on the atmosphere and climate might be the replacement of fossil fuels by alternative fuels. However, so far the effects of alternative fuels on particle emissions from aircraft engines and their ability to form contrails remain uncertain. To study the effects of alternative fuels on particle emissions and the formation of contrails, the Alternative Fuel Effects on Contrails and Cruise Emissions (ACCESS) field experiment was conducted in California. In May 2014, the DLR Falcon 20 and the NASA HU-25 jet aircraft were instrumented with an extended aerosol and trace gas payload probing different types of fuels including JP-8 and JP-8 blended with HEFA (Hydroprocessed Esters and Fatty Acids) while the NASA DC8 aircraft acted as the source aircraft for ACCESS-2. Emission measurements were taken in the DC8 exhaust plumes at aircraft cruise level between 9-12 km altitude and at distances between 50 m and 20 km behind the DC8 engines. Here, we will present results from the ACCESS-2 aerosol measurements which show a 30-60% reduction of the non-volatile (mainly black carbon) particle number concentration in the aircraft exhaust for the HEFA-blend compared to conventional JP-8 fuel. Size-resolved particle emission indices show the largest reductions for larger particle sizes suggesting that the HEFA blend contains fewer and smaller black carbon particles. We will combine the airborne measurements with a parameterization of deposition nucleation developed during a number of ice nucleation experiments at the AIDA chamber in Karlsruhe and discuss the impact of alternative fuels on the abundance of potential ice nuclei at cruise conditions.

  7. The large motor plume/material impingement test program at AEDC utilizing the four selected propellants from the small motor tests at MSFC (July, August, and September 1974), section 3

    NASA Technical Reports Server (NTRS)

    1976-01-01

    Efforts made to determine the vulnerability of Orbiter and ET materials located at various positions within exhaust plumes from test SSRM's using four different propellant formulations are discussed. Data also cover the effect on TPS materials from a single SSRM plume and dual SSRM plumes, and definitions of test SSRM plume environment at material specimen locations.

  8. Turbulent Plumes in Nature

    NASA Astrophysics Data System (ADS)

    Woods, Andrew W.

    2010-01-01

    This review describes a range of natural processes leading to the formation of turbulent buoyant plumes, largely relating to volcanic processes, in which there are localized, intense releases of energy. Phenomena include volcanic eruption columns, bubble plumes in lakes, hydrothermal plumes, and plumes beneath the ice in polar oceans. We assess how the dynamics is affected by heat transfer, particle fallout and recycling, and Earth's rotation, as well as explore some of the mixing of the ambient fluid produced by plumes in a confined geometry.

  9. Effluent sampling of Scout D and Delta launch vehicle exhausts

    NASA Technical Reports Server (NTRS)

    Hulten, W. C.; Storey, R. W.; Gregory, G. L.; Woods, D. C.; Harris, F. S., Jr.

    1974-01-01

    Characterization of engine-exhaust effluents (hydrogen chloride, aluminum oxide, carbon dioxide, and carbon monoxide) has been attempted by conducting field experiments monitoring the exhaust cloud from a Scout-Algol III vehicle launch and a Delta-Thor vehicle launch. The exhaust cloud particulate size number distribution (total number of particles as a function of particle diameter), mass loading, morphology, and elemental composition have been determined within limitations. The gaseous species in the exhaust cloud have been identified. In addition to the ground-based measurements, instrumented aircraft flights through the low-altitude, stabilized-exhaust cloud provided measurements which identified CO and HCI gases and Al2O3 particles. Measurements of the initial exhaust cloud during formation and downwind at several distances have established sampling techniques which will be used for experimental verification of model predictions of effluent dispersion and fallout from exhaust clouds.

  10. Solid propellant exhausted aluminum oxide and hydrogen chloride - Environmental considerations

    NASA Technical Reports Server (NTRS)

    Cofer, W. R., III; Winstead, E. L.; Purgold, G. C.; Edahl, R. A.

    1993-01-01

    Measurements of gaseous hydrogen chloride (HCl) and particulate aluminum oxide (Al2O3) were made during penetrations of five Space Shuttle exhaust clouds and one static ground test firing of a shuttle booster. Instrumented aircraft were used to penetrate exhaust clouds and to measure and/or collect samples of exhaust for subsequent analyses. The focus was on the primary solid rocket motor exhaust products, HCl and Al2O3, from the Space Shuttle's solid boosters. Time-dependent behavior of HCl was determined for the exhaust clouds. Composition, morphology, surface chemistry, and particle size distributions were determined for the exhausted Al2O3. Results determined for the exhaust cloud from the static test firing were complicated by having large amounts of entrained alkaline ground debris (soil) in the lofted cloud. The entrained debris may have contributed to neutralization of in-cloud HCl.

  11. Investigation of solid plume simulation criteria to produce flight plume effects on multibody configuration in wind tunnel tests

    NASA Technical Reports Server (NTRS)

    Frost, A. L.; Dill, C. C.

    1986-01-01

    An investigation to determine the sensitivity of the space shuttle base and forebody aerodynamics to the size and shape of various solid plume simulators was conducted. Families of cones of varying angle and base diameter, at various axial positions behind a Space Shuttle launch vehicle model, were wind tunnel tested. This parametric evaluation yielded base pressure and force coefficient data which indicated that solid plume simulators are an inexpensive, quick method of approximating the effect of engine exhaust plumes on the base and forebody aerodynamics of future, complex multibody launch vehicles.

  12. 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. PMID:14674797

  13. Dust Plume off Mauritania

    NASA Technical Reports Server (NTRS)

    2007-01-01

    A thick plume of dust blew off the coast of Mauritania in western Africa on October 2, 2007. The Moderate Resolution Imaging Spectroradiometer (MODIS) on NASA's Aqua satellite observed the dust plume as it headed toward the southwest over the Atlantic Ocean. In this image, the dust varies in color from nearly white to medium tan. The dust plume is easier to see over the dark background of the ocean, but the plume stretches across the land surface to the east, as well. The dust plume's structure is clearest along the coastline, where relatively clear air pockets separate distinct puffs of dust. West of that, individual pillows of dust push together to form a more homogeneous plume. Near its southwest tip, the plume takes on yet another shape, with stripes of pale dust fanning out toward the northwest. Occasional tiny white clouds dot the sky overhead, but skies are otherwise clear.

  14. Modeling Europa's dust plumes

    NASA Astrophysics Data System (ADS)

    Southworth, B. S.; Kempf, S.; Schmidt, J.

    2015-12-01

    The discovery of Jupiter's moon Europa maintaining a probably sporadic water vapor plume constitutes a huge scientific opportunity for NASA's upcoming mission to this Galilean moon. Measuring properties of material emerging from interior sources offers a unique chance to understand conditions at Europa's subsurface ocean. Exploiting results obtained for the Enceladus plume, we simulate possible Europa plume configurations, analyze particle number density and surface deposition results, and estimate the expected flux of ice grains on a spacecraft. Due to Europa's high escape speed, observing an active plume will require low-altitude flybys, preferably at altitudes of 5-100 km. At higher altitudes a plume may escape detection. Our simulations provide an extensive library documenting the possible structure of Europa dust plumes, which can be quickly refined as more data on Europa dust plumes are collected.

  15. Space Shuttle Plume Simulation Effect on Aerodynamics

    NASA Technical Reports Server (NTRS)

    Hair, L. M.

    1978-01-01

    Technology for simulating plumes in wind tunnel tests was not adequate to provide the required confidence in test data where plume induced aerodynamic effects might be significant. A broad research program was undertaken to correct the deficiency. Four tasks within the program are reported. Three of these tasks involve conducting experiments, related to three different aspects of the plume simulation problem: (1) base pressures; (2) lateral jet pressures; and (3) plume parameters. The fourth task involves collecting all of the base pressure test data generated during the program. Base pressures were measured on a classic cone ogive cylinder body as affected by the coaxial, high temperature exhaust plumes of a variety of solid propellant rockets. Valid data were obtained at supersonic freestream conditions but not at transonic. Pressure data related to lateral (separation) jets at M infinity = 4.5, for multiple clustered nozzles canted to the freestream and operating at high dynamic pressure ratios. All program goals were met although the model hardware was found to be large relative to the wind tunnel size so that operation was limited for some nozzle configurations.

  16. Remote Sensing of Aircraft Contrails Using a Field Portable Digital Array Scanned Interferometer

    NASA Technical Reports Server (NTRS)

    Smith, William Hayden

    1997-01-01

    With a Digital Array Scanned Interferometer (DASI), we have obtained proof-of-concept observations with which we demonstrate DASI capabilities for the determination of contrail properties. These include the measurement of the cloud and soot microphysical parameters, as well, the abundances of specific pollutant species such as SO(sub x) or NO(sub x). From high quality hyperspectral data and using radiative transfer methods and atmospheric chemistry analysis in the data reduction and interpretation, powerful inferences concerning cloud formation, evolution and dissipation can be made. Under this sub-topic, we will integrate DASI with computer controlled scanning of the field-of-view to direct the sensor towards contrails and exhaust plumes for tracking the emitting vehicles. The optimum DASI wavelength sensitivity range for sensing contrails is 0.35 - 2.5 micron. DASI deploys on the ground or from aircraft to observe contrails in the vicinity. This enables rapid, accurate measurement of the temporal, spatial, and chemical evolution of contrails (or other plumes or exhaust sources) with a low cost, efficient sensor.

  17. Monitoring Engine Vibrations And Spectrum Of Exhaust

    NASA Technical Reports Server (NTRS)

    Martinez, Carol L.; Randall, Michael R.; Reinert, John W.

    1991-01-01

    Real-time computation of intensities of peaks in visible-light emission spectrum of exhaust combined with real-time spectrum analysis of vibrations into developmental monitoring technique providing up-to-the-second information on conditions of critical bearings in engine. Conceived to monitor conditions of bearings in turbopump suppling oxygen to Space Shuttle main engine, based on observations that both vibrations in bearings and intensities of visible light emitted at specific wavelengths by exhaust plume of engine indicate wear and incipient failure of bearings. Applicable to monitoring "health" of other machinery via spectra of vibrations and electromagnetic emissions from exhausts. Concept related to one described in "Monitoring Bearing Vibrations For Signs Of Damage", (MFS-29734).

  18. 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.

  19. 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

  20. Dynamic pressure loads associated with twin supersonic plume resonance

    NASA Technical Reports Server (NTRS)

    Seiner, J. M.; Manning, J. C.; Ponton, M. K.

    1986-01-01

    The phenomenon of twin supersonic plume resonance is defined and studied as it pertains to high level dynamic loads in the inter-nozzle region of aircraft like the F-15 and B1-A. Using a 1/40th scale model twin jet nacelle with powered choked nozzles, it is found that intense internozzle dynamic pressures are associated with the synchrophased coupling of each plume's jet flapping mode. This condition is found most prevalent when each plume's jet flapping mode has constituent elements composed of the B-type helical instability. Suppression of these fatigue bearing loads was accomplished by simple geometric modifications to only one plume's nozzle. These modifications disrupt the natural selection of the B-type mode and thereby decouple the plumes.

  1. Representative Atmospheric Plume Development for Elevated Releases

    SciTech Connect

    Eslinger, Paul W.; Lowrey, Justin D.; McIntyre, Justin I.; Miley, Harry S.; Prichard, Andrew W.

    2014-02-01

    An atmospheric explosion of a low-yield nuclear device will produce a large number of radioactive isotopes, some of which can be measured with airborne detection systems. However, properly equipped aircraft may not arrive in the region where an explosion occurred for a number of hours after the event. Atmospheric conditions will have caused the radioactive plume to move and diffuse before the aircraft arrives. The science behind predicting atmospheric plume movement has advanced enough that the location of the maximum concentrations in the plume can be determined reasonably accurately in real time, or near real time. Given the assumption that an aircraft can follow a plume, this study addresses the amount of atmospheric dilution expected to occur in a representative plume as a function of time past the release event. The approach models atmospheric transport of hypothetical releases from a single location for every day in a year using the publically available HYSPLIT code. The effective dilution factors for the point of maximum concentration in an elevated plume based on a release of a non-decaying, non-depositing tracer can vary by orders of magnitude depending on the day of the release, even for the same number of hours after the release event. However, the median of the dilution factors based on releases for 365 consecutive days at one site follows a power law relationship in time, as shown in Figure S-1. The relationship is good enough to provide a general rule of thumb for estimating typical future dilution factors in a plume starting at the same point. However, the coefficients of the power law function may vary for different release point locations. Radioactive decay causes the effective dilution factors to decrease more quickly with the time past the release event than the dilution factors based on a non-decaying tracer. An analytical expression for the dilution factors of isotopes with different half-lives can be developed given the power law expression

  2. Flow prediction for propfan engine installation effects on transport aircraft at transonic speeds

    NASA Technical Reports Server (NTRS)

    Samant, S. S.; Yu, N. J.

    1986-01-01

    An Euler-based method for aerodynamic analysis of turboprop transport aircraft at transonic speeds has been developed. In this method, inviscid Euler equations are solved over surface-fitted grids constructed about aircraft configurations. Propeller effects are simulated by specifying sources of momentum and energy on an actuator disc located in place of the propeller. A stripwise boundary layer procedure is included to account for the viscous effects. A preliminary version of an approach to embed the exhaust plume within the global Euler solution has also been developed for more accurate treatment of the exhaust flow. The resulting system of programs is capable of handling wing-body-nacelle-propeller configurations. The propeller disks may be tractors or pushers and may represent single or counterrotation propellers. Results from analyses of three test cases of interest (a wing alone, a wing-body-nacelle model, and a wing-nacelle-endplate model) are presented. A user's manual for executing the system of computer programs with formats of various input files, sample job decks, and sample input files is provided in appendices.

  3. Modeling Europa's Dust Plumes

    NASA Astrophysics Data System (ADS)

    Southworth, B.; Kempf, S.; Schmidt, J.

    2015-12-01

    The discovery of Europa maintaining a probably sporadic water vapor plume constitutes a huge scientific opportunity for NASA's upcoming mission to this Galilean moon. Measuring the properties of material emerging from interior sources offers a unique chance to understand conditions at Europa's subsurface ocean. Exploiting results obtained for the Enceladus plume, we adjust the ejection model by Schmidt et al. [2008] to the conditions at Europa. In this way, we estimate properties of a possible, yet unobserved dust component of the Europa plume. For a size-dependent speed distribution of emerging ice particles we use the model from Kempf et al. [2010] for grain dynamics, modified to run simulations of plumes on Europa. Specifically, we model emission from the two plume locations determined from observations by Roth et al. [2014] and also from other locations chosen at the closest approach of low-altitude flybys investigated in the Europa Clipper study. This allows us to estimate expected fluxes of ice grains on the spacecraft. We then explore the parameter space of Europa dust plumes with regard to particle speed distribution parameters, plume location, and spacecraft flyby elevation. Each parameter set results in a 3-dimensional particle density structure through which we simulate flybys, and a map of particle fallback ('snowfall') on the surface of Europa. Due to the moon's high escape speed, a Europa plume will eject few to no particles that can escape its gravity, which has several further consequences: (i) For given ejection velocity a Europa plume will have a smaller scale height, with a higher particle number densities than the plume on Enceladus, (ii) plume particles will not feed the diffuse Galilean dust ring, (iii) the snowfall pattern on the surface will be more localized about the plume location, and will not induce a global m = 2 pattern as seen on Enceladus, and (iv) safely observing an active plume will require low altitude flybys, preferably at 50

  4. Heat Exhaustion, First Aid

    MedlinePlus

    ... rashes clinical tools newsletter | contact Share | Heat Exhaustion, First Aid A A A Heat exhaustion signs and symptoms ... specific to the other stages of heat illness. First Aid Guide Use a combination of the following measures ...

  5. 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

  6. The Effects of Aircraft Wake Dynamics on Contrail Development

    NASA Technical Reports Server (NTRS)

    Lewellen, D. C.; Lewellen, W. S.; Grose, W. L. (Technical Monitor)

    2001-01-01

    Results of large-eddy simulations of the development of young persistent ice contrails are presented, concentrating on the interactions between the aircraft wake dynamics and the ice cloud evolution over ages front a few seconds to approx. 30 min. The 3D unsteady evolution of the dispersing engine exhausts, trailing vortex pair interaction and breakup, and subsequent Brunt-Vaisala oscillations of the older wake plume are modeled in detail in high-resolution simulations, coupled with it bulk microphysics model for the contrail ice development. The simulations confirm that the early wake dynamics can have a strong influence on the properties of persistent contrails even at late times. The vortex dynamics are the primary determinant of the vertical extent of the contrail (until precipitate ton becomes significant): and this together with the local wind shear largely determines the horizontal extent. The ice density, ice crystal number density, and a conserved exhaust tracer all develop and disperse in different fashions from each other. The total ice crystal number can be significantly reduced due to adiabatic compression resulting from the downward motion of the vortex system, even for ambient conditions that are substantially supersaturated with respect to ice. The fraction of the initial ice crystals surviving, their spatial distribution and the ice mass distribution are all sensitive to the aircraft type, ambient humidity, assumed initial ice crystal number, and ambient turbulence conditions. There is a significant range of conditions for which a smaller transport such as a B737 produces as significant a persistent contrail as a larger transport such as a B747, even though the latter consumes almost five times as much fuel. The difficulties involved in trying to minimize persistent contrail production are discussed.

  7. COOLING TOWER PLUME MODEL

    EPA Science Inventory

    A review of recently reported cooling tower plume models yields none that is universally accepted. The entrainment and drag mechanisms and the effect of moisture on the plume trajectory are phenomena which are treated differently by various investigators. In order to better under...

  8. The dominant effect of alumina on nearfield plume radiation

    NASA Astrophysics Data System (ADS)

    Laredo, David; Netzer, David W.

    1993-11-01

    Solid propellant rocket motors can achieve high specific impulse with metal fuel additives such as aluminum. Combustion of aluminum produces condensed alumina particles. Besides causing performance losses in the nozzle, the condensed Al2O3 particles are the major source of primary smoke in the exhaust plume. The particulate matter can also have major effects upon the plume i.r. signature. High number densities of particles can block gas-phase radiation from the plume. They can also be the source of radiation, especially the larger particles which exit the nozzle not in thermal equilibrium with the gas. In the past, the expected effects of particle size on the plume i.r. signature have been determined almost exclusively from predictions made with flow and radiation codes. The aim of the present work was to investigate the role of the Al/Al2O3 particles from a highly loaded solid propellant (up to 16% in weight) on the plume radiation of a small rocket motor (5 cm in diameter). The spatial variation of particle size distribution was simultaneously measured with the overall radiation of a portion of the plume in the i.r. band (3.5-5.0 microns). In micro-motors, operating with highly aluminized solid propellant, the condensed particles in the near exhaust plume were the major source of radiation in the 3.5-5 micron wavelength band. Motors with longer residence time and operating at medium chamber pressures produced more particles in the micron sized range. The role of after burning was predominately confined to reheating of the alumina particles to a higher temperature, at which the condensed Al2O3 radiated more than gaseous species. Even with 30% Al2O3 in the plume, the plume of small motors can be considered as approximately conical in shape, with volume distributed radiating sources. Motor conditions producing larger particles in the plume core were thus found to increase plume radiation from that region. The overall apparent emissivity of the plume was between 0

  9. Stealth Plumes on Io

    NASA Technical Reports Server (NTRS)

    Johnson, T. V.; Matson, Dennis L.; Blaney, Diana L.; Veeder, Glenn J.; Davies, Ashley

    1995-01-01

    We suggest that Io's eruptive activity may include a class of previously undetected SO2 geysers. The thermodynamic models for the eruptive plumes discovered by Voyager 'involve low to moderate entropy SO2 eruptions. The resulting plumes are a mixture of solid and gas which emerge from the vent and follow essentially ballistic trajectories. We show that intrusion of silicate magma into buried SO2 deposits can create the required conditions for high entropy eruptions which proceed entirely in the vapor phase. These purely gaseous plumes would have been invisible to Voyager's instruments. Hence, we call them "stealth" plumes. Such eruptions could explain the "patchy" SO2 atmosphere inferred from recent UV and micro-wave spectral observations. The magma intrusion rate required to support the required gas production for these plumes is a negligible fraction of estimated global magma intrusion rates.

  10. Apollo video photogrammetry estimation of plume impingement effects

    NASA Astrophysics Data System (ADS)

    Immer, Christopher; Lane, John; Metzger, Philip; Clements, Sandra

    2011-07-01

    Future missions to the Moon may require numerous landings at the same site. Since the top few centimeters are loosely packed regolith, plume impingement from the Lander ejects the granular material at high velocities. Much work is needed to understand the physics of plume impingement during landing to protect hardware surrounding the landing sites. While mostly qualitative in nature, the Apollo Lunar Module landing videos can provide a wealth of quantitative information using modern photogrammetry techniques. The authors have used the digitized videos to quantify plume impingement effects of the landing exhaust on the lunar surface. The dust ejection angle from the plume is estimated at 1°-3°. The lofted particle density is estimated at 10 8-10 13 particles/m 3. Additionally, evidence for ejection of large 10-15 cm sized objects and a dependence of ejection angle on thrust are presented. Further work is ongoing to continue quantitative analysis of the landing videos.

  11. Plume interference with space shuttle range safety signals

    NASA Technical Reports Server (NTRS)

    Boynton, F. P.; Rajaseknar, P. S.

    1979-01-01

    The computational procedure for signal propagation in the presence of an exhaust plume is presented. Comparisons with well-known analytic diffraction solutions indicate that accuracy suffers when mesh spacing is inadequate to resolve the first unobstructed Fresnel zone at the plume edge. Revisions to the procedure to improve its accuracy without requiring very large arrays are discussed. Comparisons to field measurements during a shuttle solid rocket motor (SRM) test firing suggest that the plume is sharper edged than one would expect on the basis of time averaged electron density calculations. The effects, both of revisions to the computational procedure and of allowing for a sharper plume edge, are to raise the signal level near tail aspect. The attenuation levels then predicted are still high enough to be of concern near SRM burnout for northerly launches of the space shuttle.

  12. The 1995 scientific assessment of the atmospheric effects of stratospheric aircraft

    SciTech Connect

    Stolarski, R.S.; Baughcum, S.L.; Brune, W.H.; Douglass, A.R.; Fahey, D.W.; Friedl, R.R.; Liu, S.C.; Plumb, R.A.; Poole, L.R.; Wesoky, H.L.

    1995-11-01

    This report provides a scientific assessment of present knowledge concerning the impact of proposed high-speed civil transport (HSCT) aircraft on the atmosphere. It comes at the end of Phase 1 of the Atmospheric Effects of Stratospheric Aircraft element of the NASA High-Speed Research Program. The fundamental problem with stratospheric flight is that pollutant residence times are long because the stratosphere is a region of permanent temperature inversion with stable stratification. Using improved two-dimensional assessment models and detailed fleet emissions scenarios, the assessment examines the possible impact of the range of effluents from aircraft. Emphasis is placed on the effects of NO(x) and H2O on the atmospheric ozone content. Measurements in the plume of an in-flight Concorde supersonic transport indicated a large number of small particles. These measurements, coupled with model sensitivity studies, point out the importance of obtaining a more detailed understanding of the fate of sulfur in the HSCT exhaust. Uncertainties in the current understanding of the processes important for determining the overall effects of HSCT`s on the atmosphere are discussed and partially quantified. Research directions are identified to improve the quantification of uncertainties and to reduce their magnitude.

  13. The 1995 scientific assessment of the atmospheric effects of stratospheric aircraft

    NASA Technical Reports Server (NTRS)

    Stolarski, Richard S.; Baughcum, Steven L.; Brune, William H.; Douglass, Anne R.; Fahey, David W.; Friedl, Randall R.; Liu, Shaw C.; Plumb, R. Alan; Poole, Lamont R.; Wesoky, Howard L.

    1995-01-01

    This report provides a scientific assessment of our knowledge concerning the impact of proposed high-speed civil transport (HSCT) aircraft on the atmosphere. It comes at the end of Phase 1 of the Atmospheric Effects of Stratospheric Aircraft element of the NASA High-Speed Research Program. The fundamental problem with stratospheric flight is that pollutant residence times are long because the stratosphere is a region of permanent temperature inversion with stable stratification. Using improved two-dimensional assessment models and detailed fleet emissions scenarios, the assessment examines the possible impact of the range of effluents from aircraft. Emphasis is placed on the effects of NO(x) and H2O on the atmospheric ozone content. Measurements in the plume of an in-flight Concorde supersonic transport indicated a large number of small particles. These measurements, coupled with model sensitivity studies, point out the importance of obtaining a more detailed understanding of the fate of sulfur in the HSCT exhaust. Uncertainties in the current understanding of the processes important for determining the overall effects of HSCT's on the atmosphere are discussed and partially quantified. Research directions are identified to improve the quantification of uncertainties and to reduce their magnitude.

  14. Three Dimensional Monitoring of Stack Plume Dynamics by a Scanning Mie Lidar System as a Plume Watchdog Station

    NASA Astrophysics Data System (ADS)

    Saito, Yasunori; Kurata, Hidehumi; Hara, Yuta; Kobayashi, Fumitoshi; Kawahara, Takuya; Nomura, Akio

    A scanning lidar system was developed to watch the nighttime diffusion process of plume from a smokestack of a large incinerator located around 3 km from the system. Observed data sets were visualized as three dimensional images in which could be seen the diffusion pattern from any direction, and this made it easy to investigate the exhaust dynamics. Observation results showed that the original plume extended at least 1.6 km, where there was a residential area, from the smokestack increasing in diameter to about 500 m. High density aerosols originating from the smokestack were measured in that area even at midnight. The lidar system performance as a plume watchdog station was discussed from the standpoint of publichealth-related plume monitoring.

  15. D-558-2 Aircraft on lakebed

    NASA Technical Reports Server (NTRS)

    1955-01-01

    longitudinal (pitch) motions; wing and tail loads, lift, drag, and buffeting characteristics of swept-wing aircraft at transonic and supersonic speeds; and the effects of the rocket exhaust plume on lateral dynamic stability throughout the speed range. (Plume effects were a new experience for aircraft.) The number three aircraft also gathered information about the effects of external stores (bomb shapes, drop tanks) upon the aircraft's behavior in the transonic region (roughly 0.7 to 1.3 times the speed of sound). In correlation with data from other early transonic research aircraft such as the XF-92A, this information contributed to solutions to the pitch-up problem in swept-wing aircraft. The three airplanes flew a total of 313 times--123 by the number one aircraft (Bureau No. 37973--NACA 143), 103 by the second Skyrocket (Bureau No. 37974--NACA 144), and 87 by airplane number three (Bureau No. 37975--NACA 145). Skyrocket 143 flew all but one of its missions as part of the Douglas contractor program to test the airplane's performance. NACA aircraft 143 was initially powered by a Westinghouse J-34-40 turbojet engine configured only for ground take-offs, but in 1954-55 the contractor modified it to an all-rocket air-launch capability featuring an LR8-RM-6, 4-chamber Reaction Motors engine rated at 6,000 pounds of thrust at sea level (the Navy designation for the Air Force's LR-11 used in the X-1). In this configuration, NACA research pilot John McKay flew the airplane only once for familiarization on September 17, 1956. The 123 flights of NACA 143 served to validate wind-tunnel predictions of the airplane's performance, except for the fact that the airplane experienced less drag above Mach 0.85 than the wind tunnels had indicated. NACA 144 also began its flight program with a turbojet powerplant. NACA pilots Robert A. Champine and John H. Griffith flew 21 times in this configuration to test airspeed calibrations and to research longitudinal and lateral stability and control

  16. An Experimental Investigation of an Exhaust-gas-to-air Heat Exchanger for Use on Jet-stack-equipped Engines

    NASA Technical Reports Server (NTRS)

    Stalder, Jackson R; Spies, Ray J , Jr

    1948-01-01

    Tests were made to determine the loss in exhaust-jet thrust and engine power resulting from the insertion of an exhaust-gas-to-air heat exchanger in a jet-type exhaust stack of an aircraft engine. The thermal performance of the heat exchanger was also determined.

  17. Terminology and assessment methods of solid propellant rocket exhaust signatures

    NASA Astrophysics Data System (ADS)

    1993-02-01

    The Propulsion and Energetics Panel's Specialists' Meeting in autumn 1985 on Smokeless Propellants demonstrated that no common standard was available in this field and that the lack of common understanding led to misunderstanding amongst the NATO community. After some preparatory discussion, the Panel, therefore, formed Working Group Number 21 with the objectives of defining methods for the assessment of rocket motor exhaust optical properties in the visible and in the infrared range, and of recommending a terminology based on quantitative criteria. The Working Group discussed the subject in a total of eight sessions and prepared this Advisory Report. Following an Introduction and Summary there are six chapters, commencing with an Overview and continuing with Propellant Smoke Classification, Plume Primary Smoke, Plume Secondary Smoke, Plume Radiation and Plume Microwave Properties. In most cases, the conclusions and recommendations follow the chapters and are not repeated at the end of the report.

  18. Aircraft engine pollution reduction.

    NASA Technical Reports Server (NTRS)

    Rudey, R. A.

    1972-01-01

    The effect of engine operation on the types and levels of the major aircraft engine pollutants is described and the major factors governing the formation of these pollutants during the burning of hydrocarbon fuel are discussed. Methods which are being explored to reduce these pollutants are discussed and their application to several experimental research programs are pointed out. Results showing significant reductions in the levels of carbon monoxide, unburned hydrocarbons, and oxides of nitrogen obtained from experimental combustion research programs are presented and discussed to point out potential application to aircraft engines. An experimental program designed to develop and demonstrate these and other advanced, low pollution combustor design methods is described. Results that have been obtained to date indicate considerable promise for reducing advanced engine exhaust pollutants to levels significantly below current engines.

  19. Prometheus: Io's wandering plume.

    PubMed

    Kieffer, S W; Lopes-Gautier, R; McEwen, A; Smythe, W; Keszthelyi, L; Carlson, R

    2000-05-19

    Unlike any volcanic behavior ever observed on Earth, the plume from Prometheus on Io has wandered 75 to 95 kilometers west over the last 20 years since it was first discovered by Voyager and more recently observed by Galileo. Despite the source motion, the geometric and optical properties of the plume have remained constant. We propose that this can be explained by vaporization of a sulfur dioxide and/or sulfur "snowfield" over which a lava flow is moving. Eruption of a boundary-layer slurry through a rootless conduit with sonic conditions at the intake of the melted snow can account for the constancy of plume properties. PMID:10817989

  20. El Chichon - Composition of plume gases and particles

    NASA Technical Reports Server (NTRS)

    Kotra, J. P.; Finnegan, D. L.; Zoller, W. H.; Hart, M. A.; Moyers, J. L.

    1983-01-01

    Aircraft measurements were made of trace gases, atmospheric particles, and condensed acid volatiles in the plume of El Chichon volcano, Chiapas, Mexico, in November 1982. Hydrogen sulfide was the primary gaseous sulfur species in the plume at the time of collection. Concentrations of 28 elements were determined by neutron activation analysis of particulate material from the plume. The volatile elements sulfur, chlorine, arsenic, selenium, bromine, antimony, iodine, tungsten, and mercury were enriched relative to bulk pyroclastic material by factors of 60 to 20,000. Arsenic, antimony, and selenium were associated predominantly with small (not greater than 3 micrometer) particles. Calcium and sodium were present almost exclusively on larger particles and aluminum and manganese were bimodally distributed. Ashladen particulate material injected into the stratosphere during the early violent eruptions was enriched by factors of 10 to 30 relative to ash in some of the same elements observed in the quiescent plume.

  1. Small particles in plumes of Mount St. Helens

    NASA Technical Reports Server (NTRS)

    Rose, W. I.; Chuan, R. L.; Woods, D. C.

    1982-01-01

    Particles in the size range 0.1-25 microns were sampled by aircraft carrying a quartz crystal microcascade in the Mount St. Helens plume on three dates in August and September 1980. Two of the sampling dates represented 'typical' emissions of the volcano between plinian eruptions. One sampling flight was made 1-4 hours before the small plinian eruption of August 7, 1980 when the plume had become discontinuous and visibly darker. The plume sampled on August 7, before the eruption, contained mainly approximately 2-micron diameter silicic glass particles, fragments of the Mount St. Helens magma. The typical plumes sampled on September 22 and August 6 had much smaller concentrations of particles, trimodal size distributions with peaks at 10, 0.4, and 0.1 microns. The particles were largely nonsilicate and apparently represented Cu-Zn oxide (10 micron peak), Al sulfate, chloride, and oxide, and sulfuric acid (smallest size peak).

  2. Trajectories of the Mount St. Helens eruption plume

    NASA Technical Reports Server (NTRS)

    Danielsen, E. F.

    1981-01-01

    The plume of the major eruption of Mount St. Helens on May 18, 1980 penetrated 10 to 11 km into the stratosphere, attaining heights of 22 to 23 km. Wind shears rapidly converted the plume from an expanding vertical cone to a thin, slightly inclined lamina. The lamina was extruded zonally in the stratosphere as the lower part moved eastward at jet stream velocities, while the upper part slowly moved westward in the region of nonsteady transition from the westerlies to the summer stratospheric easterlies. Trajectories computed to position the NASA U-2 aircraft for sampling in the plume are described. Plume volume after 8 hours of strong volcanic emission is estimated at 2,000,000 cu km. Only about 1% of this volume is attributed to the volcano; the rest was entrained from the environment.

  3. Trajectories of the Mount St. Helens eruption plume

    SciTech Connect

    Danielsen, E.F.

    1981-01-01

    The plume of the major eruption of Mount St. Helens on 18 May 1980 penetrated 10 to 11 kilometers into the stratosphere, attaining heights of 22 to 23 kilometers. Wind shears rapidly converted the plume from expanding vertical cone to a thin, slightly inclined lamina. The lamina was extruded zonally in the stratosphere as the lower part moved eastward at jet stream velocities, while the upper part slowly moved westward in the region of nonsteady transition from the westerlies to the summer stratospheric easterlies. Trajectories computed to position the NASA U-2 aircraft for sampling in the plume are described. Plume volume after 8 hours of strong volcanic emission is estimated at 2 x 10/sup +6/ cubic kilometers. Only about 1 percent of this volume is attributed to the volcano; the rest was entrained from the environment.

  4. Volcanic ash plume identification using polarization lidar: Augustine eruption, Alaska

    USGS Publications Warehouse

    Sassen, Kenneth; Zhu, Jiang; Webley, Peter W.; Dean, K.; Cobb, Patrick

    2007-01-01

    During mid January to early February 2006, a series of explosive eruptions occurred at the Augustine volcanic island off the southern coast of Alaska. By early February a plume of volcanic ash was transported northward into the interior of Alaska. Satellite imagery and Puff volcanic ash transport model predictions confirm that the aerosol plume passed over a polarization lidar (0.694 mm wavelength) site at the Arctic Facility for Atmospheric Remote Sensing at the University of Alaska Fairbanks. For the first time, lidar linear depolarization ratios of 0.10 – 0.15 were measured in a fresh tropospheric volcanic plume, demonstrating that the nonspherical glass and mineral particles typical of volcanic eruptions generate strong laser depolarization. Thus, polarization lidars can identify the volcanic ash plumes that pose a threat to jet air traffic from the ground, aircraft, or potentially from Earth orbit.

  5. 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

    90%) from (typically lower than) those based on the extractive techniques. However, the ORS techniques were useful in providing non-intrusive real-time measurements of gaseous species in the exhaust plume, which warrants further development. The results obtained in this program validate sampling methodology and measurement techniques used for non-volatile PM aircraft emissions as described in the SAE AIR-6037.

  6. Aircraft noise prediction

    NASA Astrophysics Data System (ADS)

    Filippone, Antonio

    2014-07-01

    This contribution addresses the state-of-the-art in the field of aircraft noise prediction, simulation and minimisation. The point of view taken in this context is that of comprehensive models that couple the various aircraft systems with the acoustic sources, the propagation and the flight trajectories. After an exhaustive review of the present predictive technologies in the relevant fields (airframe, propulsion, propagation, aircraft operations, trajectory optimisation), the paper addresses items for further research and development. Examples are shown for several airplanes, including the Airbus A319-100 (CFM engines), the Bombardier Dash8-Q400 (PW150 engines, Dowty R408 propellers) and the Boeing B737-800 (CFM engines). Predictions are done with the flight mechanics code FLIGHT. The transfer function between flight mechanics and the noise prediction is discussed in some details, along with the numerical procedures for validation and verification. Some code-to-code comparisons are shown. It is contended that the field of aircraft noise prediction has not yet reached a sufficient level of maturity. In particular, some parametric effects cannot be investigated, issues of accuracy are not currently addressed, and validation standards are still lacking.

  7. Aircraft Wake RCS Measurement

    NASA Technical Reports Server (NTRS)

    Gilson, William H.

    1994-01-01

    A series of multi-frequency radar measurements of aircraft wakes at altitudes of 5,000 to 25,00 ft. were performed at Kwajalein, R.M.I., in May and June of 1990. Two aircraft were tested, a Learjet 35 and a Lockheed C-5A. The cross-section of the wake of the Learjet was too small for detection at Kwajalein. The wake of the C-5A, although also very small, was detected and measured at VHF, UHF, L-, S-, and C-bands, at distances behind the aircraft ranging from about one hundred meters to tens of kilometers. The data suggest that the mechanism by which aircraft wakes have detectable radar signatures is, contrary to previous expectations, unrelated to engine exhaust but instead due to turbulent mixing by the wake vortices of pre-existing index of refraction gradients in the ambient atmosphere. These measurements were of necessity performed with extremely powerful and sensitive instrumentation radars, and the wake cross-section is too small for most practical applications.

  8. D-558-2 Aircraft on lakebed

    NASA Technical Reports Server (NTRS)

    1954-01-01

    gathered a great deal of data about pitch-up and the coupling of lateral (yaw) and longitudinal (pitch) motions; wing and tail loads, lift, drag, and buffeting characteristics of swept-wing aircraft at transonic and supersonic speeds; and the effects of the rocket exhaust plume on lateral dynamic stability throughout the speed range. (Plume effects were a new experience for aircraft.) The number three aircraft also gathered information about the effects of external stores (bomb shapes, drop tanks) upon the aircraft's behavior in the transonic region (roughly 0.7 to 1.3 times the speed of sound). In correlation with data from other early transonic research aircraft such as the XF-92A, this information contributed to solutions to the pitch-up problem in swept-wing aircraft. The three airplanes flew a total of 313 times--123 by the number one aircraft (Bureau No. 37973--NACA 143), 103 by the second Skyrocket (Bureau No. 37974--NACA 144), and 87 by airplane number three (Bureau No. 37975--NACA 145). Skyrocket 143 flew all but one of its missions as part of the Douglas contractor program to test the airplane's performance. NACA aircraft 143 was initially powered by a Westinghouse J-34-40 turbojet engine configured only for ground take-offs, but in 1954-55 the contractor modified it to an all-rocket air-launch capability featuring an LR8-RM-6, 4-chamber Reaction Motors engine rated at 6,000 pounds of thrust at sea level (the Navy designation for the Air Force's LR-11 used in the X-1). In this configuration, NACA research pilot John McKay flew the airplane only once for familiarization on September 17, 1956. The 123 flights of NACA 143 served to validate wind-tunnel predictions of the airplane's performance, except for the fact that the airplane experienced less drag above Mach 0.85 than the wind tunnels had indicated. NACA 144 also began its flight program with a turbojet powerplant. NACA pilots Robert A. Champine and John H. Griffith flew 21 times in this configuration to test

  9. CHLORINATED SOLVENT PLUME CONTROL

    EPA Science Inventory

    This lecture will cover recent success in controlling and assessing the treatment of shallow ground water plumes of chlorinated solvents, other halogenated organic compounds, and methyl tert-butyl ether (MTBE).

  10. Methane Plumes on Mars

    NASA Video Gallery

    Spectrometer instruments attached to several telescopes detect plumes of methane emitted from Mars during its summer and spring seasons. High levels of methane are indicated by warmer colors. The m...

  11. Exhaust gas purification device

    SciTech Connect

    Fujiwara, H.; Hibi, T.; Sayo, S.; Sugiura, Y.; Ueda, K.

    1980-02-19

    The exhaust gas purification device includes an exhaust manifold , a purification cylinder connected with the exhaust manifold through a first honey-comb shaped catalyst, and a second honeycomb shaped catalyst positioned at the rear portion of the purification cylinder. Each catalyst is supported by steel wool rings including coarse and dense portions of steel wool. The purification device further includes a secondary air supplying arrangement.

  12. Sulfur plumes off Namibia

    NASA Technical Reports Server (NTRS)

    2002-01-01

    Sulfur plumes rising up from the bottom of the ocean floor produce colorful swirls in the waters off the coast of Namibia in southern Africa. The plumes come from the breakdown of marine plant matter by anaerobic bacteria that do not need oxygen to live. This image was acquired by the Moderate Resolution Imaging Spectroradiometer (MODIS) on the Terra satellite on April 24, 2002 Credit: Jacques Descloitres, MODIS Land Rapid Response Team, NASA/GSFC

  13. 3D-CFD Investigation of Contrails and Volatile Aerosols Produced in the Near-Field of an Aircraft Wake

    NASA Astrophysics Data System (ADS)

    Garnier, F.; Ghedhaifi, W.; Vancassel, X.; Khou, J. C.; Montreuil, E.

    2015-12-01

    Civil aviation contributes to degradation of air quality around airport (SOx, NOx, speciated hydrocarbons,…) and climate change through its emissions of greenhouse gases (CO2, water vapor), as well as particulate matters. These particles include soot particles formed in the combustor, volatile aerosols and contrails generated in the aircraft wake. Although the aircraft emissions represent today only about 3% of all those produced on the surface of the earth by other anthropogenic sources, they are mostly released in the very sensitive region of the upper troposphere/lower stratosphere. These emissions have a radiative effect reinforced by specific physical and chemical processes at high altitudes, such as cloud formation and ozone production. In this context, most of the work to-date assessed that the actual effect of aviation on the climate are affected by very large uncertainties, partly due to lack of knowledge on the mechanisms of new particles formation and growth processes in the exhaust plume of the aircraft. The engine exhaust gases are mixed in the ambient air under the influence of the interaction between the jet engine and the wing tip vortices. The characteristics of vortices as well as their interaction with the jet depend on the aircraft airframe especially on the wing geometry and the engine position (distance from the wing tip). The aim of this study is to examine the influence of aircraft parameters on contrail formation using a 3D CFD calculation based on a RANS (Reynolds Average Navier-Stokes) approach. Numerical simulations have been performed using CEDRE, the multiphysics ONERA code for energetics. CEDRE is a CFD code using finite volume methods and unstructured meshes. These meshes are especially appropriate when complex geometries are used. A transport model has been used for condensation of water vapor onto ice particles. Growth is evaluated using a modified Fick's law to mass transfer on particles. In this study, different aircraft

  14. Electrification of volcanic plumes

    NASA Astrophysics Data System (ADS)

    Mather, T. A.; Harrison, R. G.

    2006-07-01

    Volcanic lightning, perhaps the most spectacular consequence of the electrification of volcanic plumes, has been implicated in the origin of life on Earth, and may also exist in other planetary atmospheres. Recent years have seen volcanic lightning detection used as part of a portfolio of developing techniques to monitor volcanic eruptions. Remote sensing measurement techniques have been used to monitor volcanic lightning, but surface observations of the atmospheric electric Potential Gradient (PG) and the charge carried on volcanic ash also show that many volcanic plumes, whilst not sufficiently electrified to produce lightning, have detectable electrification exceeding that of their surrounding environment. Electrification has only been observed associated with ash-rich explosive plumes, but there is little evidence that the composition of the ash is critical to its occurrence. Different conceptual theories for charge generation and separation in volcanic plumes have been developed to explain the disparate observations obtained, but the ash fragmentation mechanism appears to be a key parameter. It is unclear which mechanisms or combinations of electrification mechanisms dominate in different circumstances. Electrostatic forces play an important role in modulating the dry fall-out of ash from a volcanic plume. Beyond the local electrification of plumes, the higher stratospheric particle concentrations following a large explosive eruption may affect the global atmospheric electrical circuit. It is possible that this might present another, if minor, way by which large volcanic eruptions affect global climate. The direct hazard of volcanic lightning to communities is generally low compared to other aspects of volcanic activity.

  15. Plume Mitigation for Mars Terminal Landing: Soil Stabilization Project

    NASA Technical Reports Server (NTRS)

    Hintze, Paul E.

    2014-01-01

    Kennedy Space Center (KSC) has led the efforts for lunar and Martian landing site preparation, including excavation, soil stabilization, and plume damage prediction. There has been much discussion of sintering but until our team recently demonstrated it for the lunar case there was little understanding of the serious challenges. Simplistic sintering creates a crumbly, brittle, weak surface unsuitable for a rocket exhaust plume. The goal of this project is to solve those problems and make it possible to land a human class lander on Mars, making terminal landing of humans on Mars possible for the first time.

  16. Controlling plume deflection by acoustic excitation - An experimental demonstration

    NASA Astrophysics Data System (ADS)

    Ahuja, K. K.

    1990-10-01

    Effect of imposing an external sound field on a Coanda jet was investigated experimentally. It was found that the exhaust angle of a Coanda plume can be varied by changing the level of excitation. Limited experiments were also performed in a wind tunnel to study the effects of flight simulation on plume deflection controllability by sound using a hollow airfoil fitted with a Coanda jet. Pressure coefficients are measured over this airfoil with and without acoustic excitation of the Coanda Jet. This exploratory study provided a number of new ideas for future work for controlling flow over curved surfaces.

  17. Fine particle and organic vapor emissions from staged tests of an in-use aircraft engine

    NASA Astrophysics Data System (ADS)

    Presto, Albert A.; Nguyen, Ngoc T.; Ranjan, Manish; Reeder, Aaron J.; Lipsky, Eric M.; Hennigan, Christopher J.; Miracolo, Marissa A.; Riemer, Daniel D.; Robinson, Allen L.

    2011-07-01

    Staged tests were conducted to measure the particle and vapor emissions from a CFM56-2B1 gas-turbine engine mounted on a KC-135T Stratotanker airframe at different engine loads. Exhaust was sampled using a rake inlet installed 1-m downstream of the engine exit plane of a parked and chocked aircraft and a dilution sampler and portable smog chamber were used to investigate the particulate matter (PM) emissions. Total fine PM mass emissions were highest at low (4%) and high (85%) load and lower at intermediate loads (7% and 30%). PM mass emissions at 4% load are dominated by organics, while at 85% load elemental carbon is dominant. Quantifying the primary organic aerosol (POA) emissions is complicated by substantial filter sampling artifacts. Partitioning experiments reveal that the majority of the POA is semivolatile; for example, the POA emission factor changed by a factor of two when the background organic aerosol concentration was increased from 0.7 to 4 μg m -3. Therefore, one cannot define a single non-volatile PM emission factor for aircraft exhaust. The gas- and particle-phase organic emissions were comprehensively characterized by analyzing canister, sorbent and filter samples with gas-chromatography/mass-spectrometry. Vapor-phase organic emissions are highest at 4% load and decrease with increasing load. Low-volatility organics (less volatile than a C 12n-alkane) contributed 10-20% of the total organic emissions. The low-volatility organic emissions contain signatures of unburned fuel and aircraft lubricating oil but are dominated by an unresolved complex mixture (UCM) of presumably branched and cyclic alkanes. Emissions at all loads contain more low-volatility organic vapors than POA; thus secondary organic aerosol formation in the aging plume will likely exceed POA emissions.

  18. RAXJET- TRANSONIC, AXISYMMETRIC FLOW OVER NOZZLE AFTERBODIES WITH SUPERSONIC JET EXHAUSTS

    NASA Technical Reports Server (NTRS)

    Wilmoth, R. G.

    1994-01-01

    The nozzle afterbody is one of the main drag-producing components of an aircraft propulsion system. Thus, considerable effort has been devoted to developing techniques for predicting the afterbody flow field and drag. The RAXJET computer program was developed to predict the transonic, axisymmetric flow over nozzle afterbodies with supersonic jet exhausts and includes the effects of boundary-layer displacement, separation, jet entrainment, and inviscid jet plume blockage. RAXJET iteratively combines the South-Jameson relaxation procedure, the Reshotko-Tucker boundary-layer solution, the Presz separation model, the Dash-Pergament mixing model, and the Dash-Thorpe inviscid plume model into a single, comprehensive model. The approach taken in the RAXJET program requires considerably less computational time than the Navier-Stokes solutions and generally yields results of comparable accuracy. In RAXJET, the viscous-inviscid interaction model is constructed by dividing the afterbody flow field into six separate computational regions: (1) The inviscid external flow solution is based on the relaxation procedure of South and Jameson for solving the exact nonlinear potential flow equation in nonconservative form. (2) The flow field in the inviscid jet exhaust is solved by explicit spatial marching of the conservative finite-difference form of the inviscid flow equations for a uniform composition gas mixture. (3) The properties in the attached boundary-layer region are solved by a modified version of the Reshotko-Tucker integral method for turbulent flows. (4) The analysis of the separated flow region consists of predicting the separation location and calculating the discriminating streamline shape. (5) The jet wake region is determined by either a simple extrapolation model or by an integral method that accounts for entrainment effects. (6) The displacement-thickness distribution arising from entrainment into the jet mixing layer is calculated by the overlaid mixing model

  19. Scalable hardbody and plume optical signatures

    NASA Astrophysics Data System (ADS)

    Crow, Dennis R.; Hawes, Fred; Braunstein, Matthew; Coker, Charles F.; Smith, Thomas, Jr.

    2004-08-01

    The Fast Line-of-sight Imagery for Target and Exhaust Signatures (FLITES) is a High Performance Computing (HPC-CHSSI) and Missile Defense Agency (MDA) funded effort that provides a scalable program to compute highly resolved temporal, spatial, and spectral hardbody and plume optical signatures. Distributed processing capabilities are included to allow complex, high fidelity, solutions to be generated quickly generated. The distributed processing logic includes automated load balancing algorithms to facilitate scalability using large numbers of processors. To enhance exhaust plume optical signature capabilities, FLITES employs two different radiance transport algorithms. The first algorithm is the traditional Curtis-Godson bandmodel approach and is provided to support comparisons to historical results and high-frame rate production requirements. The second algorithm is the Quasi Bandmodel Line-by-line (QBL) approach, which uses randomly placed "cloned" spectral lines to yield highly resolved radiation spectra for increased accuracy while maintaining tractable runtimes. This capability will provide a significant advancement over the traditional SPURC/SIRRM radiance transport methodology.

  20. Method of hybrid plume plasma propulsion

    NASA Technical Reports Server (NTRS)

    Chang, Franklin R. (Inventor)

    1990-01-01

    A technique for producing thrust by generating a hybrid plume plasma exhaust is disclosed. A plasma flow is generated and introduced into a nozzle which features one or more inlets positioned to direct a flow of neutral gas about the interior of the nozzle. When such a neutral gas flow is combined with the plasma flow within the nozzle, a hybrid plume is constructed including a flow of hot plasma along the center of the nozzle surrounded by a generally annular flow of neutral gas, with an annular transition region between the pure plasma and the neutral gas. The temperature of the outer gas layer is below that of the pure plasma and generally separates the pure plasma from the interior surfaces of the nozzle. The neutral gas flow both insulates the nozzle walls from the high temperatures of the plasma flow and adds to the mass flow rate of the hybrid exhaust. The rate of flow of neutral gas into the interior of the nozzle may be selectively adjusted to control the thrust and specific impulse of the device.

  1. Electrification of volcanic plumes

    NASA Astrophysics Data System (ADS)

    Mather, T. A.; Harrison, R. G.

    We present a review of our current understanding of the electrification of volcanic plumes on Earth and discuss the possible implications both in terms of the volcanic monitoring, early Earth evolution and planetary exploration. Volcanic lightning is perhaps the most spectacular consequence of the electrification of volcanic plumes. Recent years have seen volcanic lightning detection used as part of a portfolio of developing techniques to monitor volcanic eruptions. Remote sensing measurement techniques have been used to monitor volcanic lightning, but surface observations of the atmospheric electric Potential Gradient (PG) and the charge carried on volcanic ash also show that many volcanic plumes, whilst not sufficiently electrified to produce lightning, have detectable electrification exceeding that of their surrounding environment. Electrification has only been observed associated with ash-rich explosive plumes, but there is little evidence that the composition of the ash is critical to its occurrence. Different conceptual theories for charge generation and separation in volcanic plumes have been developed to explain the disparate observations obtained, but the ash fragmentation mechanism appears to be a key parameter. It is unclear which mechanisms or combinations of electrification mechanisms dominate in different circumstances. Electrostatic forces play an important role in modulating the dry fall-out of ash from a volcanic plume. Beyond the local electrification of plumes, the higher stratospheric particle concentrations following a large explosive eruption may affect the global atmospheric electrical circuit. It is possible that this might present another, if minor, way by which large volcanic eruptions affect global climate. Volcanic lightning has been implicated in a number of ways in the origin of life on Earth, and may also exist in other planetary atmospheres where measurements of its occurrence might give clues about the nature of volcanism on other

  2. Immune Exhaustion and Transplantation.

    PubMed

    Sanchez-Fueyo, A; Markmann, J F

    2016-07-01

    Exhaustion of lymphocyte function through chronic exposure to a high load of foreign antigen is well established for chronic viral infection and antitumor immunity and has been found to be associated with a distinct molecular program and characteristic cell surface phenotype. Although exhaustion has most commonly been studied in the context of CD8 viral responses, recent studies indicate that chronic antigen exposure may affect B cells, NK cells and CD4 T cells in a parallel manner. Limited information is available regarding the extent of lymphocyte exhaustion development in the transplant setting and its impact on anti-graft alloreactivity. By analogy to the persistence of a foreign virus, the large mass of alloantigen presented by an allograft in chronic residence could provide an ideal setting for exhausting donor-reactive T cells. The extent of T cell exhaustion occurring with various allografts, the kinetics of its development, whether exhaustion is influenced positively or negatively by different immunosuppressants, and the impact of exhaustion on graft survival and tolerance development remains a fertile area for investigation. Harnessing or encouraging the natural processes of exhaustion may provide a novel means to promote graft survival and transplantation tolerance. PMID:26729653

  3. Duplex tab exhaust nozzle

    NASA Technical Reports Server (NTRS)

    Gutmark, Ephraim Jeff (Inventor); Martens, Steven (nmn) (Inventor)

    2012-01-01

    An exhaust nozzle includes a conical duct terminating in an annular outlet. A row of vortex generating duplex tabs are mounted in the outlet. The tabs have compound radial and circumferential aft inclination inside the outlet for generating streamwise vortices for attenuating exhaust noise while reducing performance loss.

  4. Diesel engine exhaust oxidizer

    SciTech Connect

    Kammel, R.A.

    1992-06-16

    This patent describes a diesel engine exhaust oxidizing device. It comprises: an enclosure having an inlet for receiving diesel engine exhaust, a main flow path through the enclosure to an outlet of the enclosure, a by-ass through the enclosure, and a microprocessor control means.

  5. Torsional vibration of aircraft engines

    NASA Technical Reports Server (NTRS)

    Lurenbaum, Karl

    1932-01-01

    Exhaustive torsional-vibration investigations are required to determine the reliability of aircraft engines. A general outline of the methods used for such investigations and of the theoretical and mechanical means now available for this purpose is given, illustrated by example. True vibration diagrams are usually obtained from vibration measurements on the completed engine. Two devices for this purpose and supplementing each other, the D.V.L. torsiograph and the D.V.L. torsion recorder, are described in this report.

  6. Exhaust purification apparatus

    SciTech Connect

    Shinzawa, M.; Ushimura, S.

    1987-05-05

    An exhaust purification apparatus is described for use in an internal combustion engine having an exhaust conduit through which exhaust particles are discharged together with exhaust gas to the atmosphere. Included is an outer shell having an inlet connected to the exhaust conduit and an outlet connected to the atmosphere. The outer shell contains a trap element and a regenerative burner located upstream of the trap element, the regenerative burner comprising: a cylindrical hollow member fixed to the liner and extending within a combustion chamber to define an evaporation chamber, a glow plug for igniting the mixture supplied into the evaporated chamber when actuated; and a control unit responsive to a regeneration requirement for actuating the glow plug and supplying an air-fuel mixture into the evaporation chamber through the mixture conduit.

  7. A Brilliant Plume

    NASA Technical Reports Server (NTRS)

    2007-01-01

    The Long Range Reconnaissance Imager (LORRI) on New Horizons captured another dramatic picture of Jupiter's moon Io and its volcanic plumes, 19 hours after the spacecraft's closest approach to Jupiter on Feb. 28, 2007. LORRI took this 75 millisecond exposure at 0035 Universal Time on March 1, 2007, when Io was 2.3 million kilometers (1.4 million miles) from the spacecraft.

    Io's dayside is deliberately overexposed to bring out faint details in the plumes and on the moon's night side. The continuing eruption of the volcano Tvashtar, at the 1 o'clock position, produces an enormous plume roughly 330 kilometers (200 miles) high, which is illuminated both by sunlight and 'Jupiter light.'

    The shadow of Io, cast by the Sun, slices across the plume. The plume is quite asymmetrical and has a complicated wispy texture, for reasons that are still mysterious. At the heart of the eruption incandescent lava, seen here as a brilliant point of light, is reminding scientists of the fire fountains spotted by the Galileo Jupiter orbiter at Tvashtar in 1999.

    The sunlit plume faintly illuminates the surface underneath. 'New Horizons and Io continue to astonish us with these unprecedented views of the solar system's most geologically active body' says John Spencer, deputy leader of the New Horizons Jupiter Encounter Science Team and an Io expert from Southwest Research Institute.

    Because this image shows the side of Io that faces away from Jupiter, the large planet does not illuminate the moon's night side except for an extremely thin crescent outlining the edge of the disk at lower right. Another plume, likely from the volcano Masubi, is illuminated by Jupiter just above this lower right edge. A third and much fainter plume, barely visible at the 2 o'clock position, could be the first plume seen from the volcano Zal Patera.

    As in other New Horizons images of Io, mountains catch the setting Sun just beyond the terminator (the line dividing day and night

  8. 14 CFR 34.64 - Sampling and analytical procedures for measuring gaseous exhaust emissions.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... Register in accordance with 5 U.S.C. 552(a) and 1 CFR part 51. This document can be obtained from the... ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT FUEL VENTING AND EXHAUST EMISSION REQUIREMENTS FOR TURBINE... Turbine Engines) § 34.64 Sampling and analytical procedures for measuring gaseous exhaust emissions....

  9. 40 CFR 87.23 - Exhaust emission standards for Tier 6 and Tier 8 engines.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 21 2012-07-01 2012-07-01 false Exhaust emission standards for Tier 6 and Tier 8 engines. 87.23 Section 87.23 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) Definitions. Exhaust Emissions (New Aircraft Gas Turbine Engines) §...

  10. 14 CFR 34.64 - Sampling and analytical procedures for measuring gaseous exhaust emissions.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... Register in accordance with 5 U.S.C. 552(a) and 1 CFR part 51. This document can be obtained from the... ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT FUEL VENTING AND EXHAUST EMISSION REQUIREMENTS FOR TURBINE... Turbine Engines) § 34.64 Sampling and analytical procedures for measuring gaseous exhaust emissions....

  11. 14 CFR 34.64 - Sampling and analytical procedures for measuring gaseous exhaust emissions.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... Register in accordance with 5 U.S.C. 552(a) and 1 CFR part 51. This document can be obtained from the... ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT FUEL VENTING AND EXHAUST EMISSION REQUIREMENTS FOR TURBINE... Turbine Engines) § 34.64 Sampling and analytical procedures for measuring gaseous exhaust emissions....

  12. 40 CFR 87.82 - Sampling and analytical procedures for measuring smoke exhaust emissions.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... measuring smoke exhaust emissions. 87.82 Section 87.82 Protection of Environment ENVIRONMENTAL PROTECTION... Test Procedures for Engine Smoke Emissions (Aircraft Gas Turbine Engines) § 87.82 Sampling and analytical procedures for measuring smoke exhaust emissions. The system and procedures for sampling...

  13. Effects of entrained water and strong turbulence on afterburning within solid rocket motor plumes

    NASA Technical Reports Server (NTRS)

    Gomberg, R. I.; Wilmoth, R. G.

    1978-01-01

    During the first few seconds of the space shuttle trajectory, the solid rocket boosters will be in the proximity of the launch pad. Because of the launch pad structures and the surface of the earth, the turbulent mixing experienced by the exhaust gases will be greatly increased over that for the free flight situation. In addition, a system will be present, designed to protect the lifting vehicle from launch structure vibrations, which will inject quantities of liquid water into the hot plume. The effects of these two phenomena on the temperatures, chemical composition, and flow field present in the afterburning solid rocket motor exhaust plumes of the space shuttle were studied. Results are included from both a computational model of the afterburning and supporting measurements from Titan 3 exhaust plumes taken at Kennedy Space Center with infrared scanned radiometers.

  14. Test data from small solid propellant rocket motor plume measurements (FA-21)

    NASA Technical Reports Server (NTRS)

    Hair, L. M.; Somers, R. E.

    1976-01-01

    A program is described for obtaining a reliable, parametric set of measurements in the exhaust plumes of solid propellant rocket motors. Plume measurements included pressures, temperatures, forces, heat transfer rates, particle sampling, and high-speed movies. Approximately 210,000 digital data points and 15,000 movie frames were acquired. Measurements were made at points in the plumes via rake-mounted probes, and on the surface of a large plate impinged by the exhaust plume. Parametric variations were made in pressure altitude, propellant aluminum loading, impinged plate incidence angle and distance from nozzle exit to plate or rake. Reliability was incorporated by continual use of repeat runs. The test setup of the various hardware items is described along with an account of test procedures. Test results and data accuracy are discussed. Format of the data presentation is detailed. Complete data are included in the appendix.

  15. Particulate exhaust emissions from an experimental combustor. [gas turbine engine

    NASA Technical Reports Server (NTRS)

    Norgren, C. T.; Ingebo, R. D.

    1975-01-01

    The concentration of dry particulates (carbon) in the exhaust of an experimental gas turbine combustor was measured at simulated takeoff operating conditions and correlated with the standard smoke-number measurement. Carbon was determined quantitatively from a sample collected on a fiberglass filter by converting the carbon in the smoke sample to carbon dioxide and then measuring the volume of carbon dioxide formed by gas chromatography. At a smoke of 25 (threshold of visibility of the smoke plume for large turbojets) the carbon concentration was 2.8 mg carbon/cu m exhaust gas, which is equivalent to an emission index of 0.17 g carbon/kg fuel.

  16. Aircraft Design

    NASA Technical Reports Server (NTRS)

    Bowers, Albion H. (Inventor); Uden, Edward (Inventor)

    2016-01-01

    The present invention is an aircraft wing design that creates a bell shaped span load, which results in a negative induced drag (induced thrust) on the outer portion of the wing; such a design obviates the need for rudder control of an aircraft.

  17. Aircraft Noise

    NASA Astrophysics Data System (ADS)

    Michel, Ulf; Dobrzynski, Werner; Splettstoesser, Wolf; Delfs, Jan; Isermann, Ullrich; Obermeier, Frank

    Aircraft industry is exposed to increasing public pressure aiming at a continuing reduction of aircraft noise levels. This is necessary to both compensate for the detrimental effect on noise of the expected increase in air traffic and improve the quality of living in residential areas around airports.

  18. CFD Analysis of Nozzle Jet Plume Effects on Sonic Boom Signature

    NASA Technical Reports Server (NTRS)

    Bui, Trong T.

    2009-01-01

    A computational fluid dynamics study is conducted to examine nozzle exhaust jet plume effects on the Sonic boom signature of a supersonic aircraft. A simplified axisymmetric nozzle geometry, representative of the nozzle on the NASA Dryden NF-15B Lift and Nozzle Change Effects on Tail Shock research airplane, is considered. The computational fluid dynamics code is validated using available wind-tunnel sonic boom experimental data. The effects of grid size, spatial order of accuracy. grid type, and flow viscosity on the accuracy of the predicted sonic boom pressure signature are quantified. Grid lines parallel to the Mach wave direction are found to give the best results. Second-order accurate upwind methods are required as a minimum for accurate sonic boom simulations. The highly underexpanded nozzle flow is found to provide significantly more reduction in the tail shock strength in the sonic boom N-wave pressure signature than perfectly expanded and overexpanded nozzle flows. A tail shock train in the sonic boom signature is observed for the highly underexpanded nozzle flow. Axisymmetric computational fluid dynamics simulations show the flow physics inside the F-15 nozzle to be nonisentropic and complex.

  19. Collapse in Thermal Plumes

    NASA Astrophysics Data System (ADS)

    Pears, M. I.; Lithgow-Bertelloni, C. R.; Dobson, D. P.; Davies, R.

    2013-12-01

    Collapsing thermal plumes have been investigated through experimental and numerical simulations. Collapsing plumes are an uncommon fluid dynamical phenomenon, usually seen when the buoyancy source is turned off. A series of fluid dynamical experiments were conducted on thermal plumes at a variety of temperature and viscosity contrasts, in a 26.5 cm^3 cubic tank heated by a constant temperature heater 2 cm in diameter and no-slip bottom and top surfaces. Working fluids included Lyle's Golden Syrup and ADM's Liquidose 436 syrup, which have strongly-temperature dependent viscosity and high Pr number (10^3-10^7 at experimental conditions). Visualisation included white light shadowgraphs and PIV of the central plane. Temperature contrasts ranged from 3-60°C, and two differing forms of collapse were identified. At very low temperature differences 'no rise' collapse was discovered, where the plumes stagnate in the lower third of the tank before collapsing. At temperature differences between 10-23°C normal evolution occurred until 'lens shape' collapse developed between midway and two-thirds of the distance from the base. The lens shape originated in the top of the conduit and was present throughout collapse. At temperatures above ΔT=23°C the plumes follow the expected growth and shape and flatten out at the top of the tank. Thermal collapse remains difficult to explain given experimental conditions (continuous heating). Instead it is possible that small density differences arising from crystallization at ambient temperatures changes plume buoyancy-inducing collapse. We show results on the evolution of the refractive index of the syrup through time to ascertain this possibility. Preliminary numerical results using Fluidity will be presented to explore a greater parameter range of viscosity contrasts and tank aspect ratios.

  20. Io Pele plume

    NASA Technical Reports Server (NTRS)

    2000-01-01

    Voyager 1 took this narrow-angle camera image on 5 March 1979 from a distance of 450,000 kilometers. At this geometry, the camera looks straight down through a volcanic plume at one of Io's most active volcanos, Pele. The large heart-shaped feature is the region where Pele's plume falls to the surface. At the center of the 'heart' is the small dark fissure that is the source of the eruption. The Voyager Project is managed by the Jet Propulsion Laboratory for NASA's Office of Space Science.

  1. Evidence for mantle plumes?

    PubMed

    Anderson, Don L; Natland, James H

    2007-11-22

    Geophysical hotspots have been attributed to partially molten asthenosphere, fertile blobs, small-scale convection and upwellings driven by core heat. Most are short-lived or too close together to be deeply seated, and do not have anomalous heat flow or temperature; many are related to tectonic features. Bourdon et al. investigate the dynamics of mantle plumes from uranium-series geochemistry and interpret their results as evidence for thermal plumes. Here we show why alternative mechanisms of upwelling and melting should be considered. PMID:18033248

  2. Exhaust gas afterburner

    SciTech Connect

    Hudson, S.J. Jr.

    1986-12-23

    This patent describes an exhaust gas afterburner device adapted for installation between an exhaust manifold and a corresponding portion of the engine block of an internal combustion engine. The device comprises: a spacer sandwiched between portions of two sheet metal members forming a gasket section of the device, the gasket section surrounding at least one exhaust gas port, a plenum section formed by remaining portions of the members, and wall sections defining passageways extending from the interior of the plenum section to the port and an air supply inlet on the plenum.

  3. Simulation of Low-density Nozzle Plumes in Non-zero Ambient Pressures

    NASA Technical Reports Server (NTRS)

    Chung, Chan-Hong; Dewitt, Kenneth J.; Stubbs, Robert M.; Penko, Paul F.

    1994-01-01

    The direct simulation Monte-Carlo (DSMC) method was applied to the analysis of low-density nitrogen plumes exhausting from a small converging-diverging nozzle into finite ambient pressures. Two cases were considered that simulated actual test conditions in a vacuum facility. The numerical simulations readily captured the complicated flow structure of the overexpanded plumes adjusting to the finite ambient pressures, including Mach disks and barrel shaped shocks. The numerical simulations compared well to experimental data of Rothe.

  4. Simulation of low-density nozzle plumes in non-zero ambient pressures

    NASA Astrophysics Data System (ADS)

    Chung, Chan-Hong; Dewitt, Kenneth J.; Stubbs, Robert M.; Penko, Paul F.

    1994-02-01

    The direct simulation Monte-Carlo (DSMC) method was applied to the analysis of low-density nitrogen plumes exhausting from a small converging-diverging nozzle into finite ambient pressures. Two cases were considered that simulated actual test conditions in a vacuum facility. The numerical simulations readily captured the complicated flow structure of the overexpanded plumes adjusting to the finite ambient pressures, including Mach disks and barrel shaped shocks. The numerical simulations compared well to experimental data of Rothe.

  5. 14 CFR 34.82 - Sampling and analytical procedures for measuring smoke exhaust emissions.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... Director of the Federal Register in accordance with 5 U.S.C. 552(a) and 1 CFR part 51. This document can be..., DEPARTMENT OF TRANSPORTATION AIRCRAFT FUEL VENTING AND EXHAUST EMISSION REQUIREMENTS FOR TURBINE ENGINE POWERED AIRPLANES Test Procedures for Engine Smoke Emissions (Aircraft Gas Turbine Engines) §...

  6. 14 CFR 34.82 - Sampling and analytical procedures for measuring smoke exhaust emissions.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... Director of the Federal Register in accordance with 5 U.S.C. 552(a) and 1 CFR part 51. This document can be..., DEPARTMENT OF TRANSPORTATION AIRCRAFT FUEL VENTING AND EXHAUST EMISSION REQUIREMENTS FOR TURBINE ENGINE POWERED AIRPLANES Test Procedures for Engine Smoke Emissions (Aircraft Gas Turbine Engines) §...

  7. 14 CFR 34.82 - Sampling and analytical procedures for measuring smoke exhaust emissions.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... Director of the Federal Register in accordance with 5 U.S.C. 552(a) and 1 CFR part 51. This document can be..., DEPARTMENT OF TRANSPORTATION AIRCRAFT FUEL VENTING AND EXHAUST EMISSION REQUIREMENTS FOR TURBINE ENGINE POWERED AIRPLANES Test Procedures for Engine Smoke Emissions (Aircraft Gas Turbine Engines) §...

  8. Technologies for Aircraft Noise Reduction

    NASA Technical Reports Server (NTRS)

    Huff, Dennis L.

    2006-01-01

    Technologies for aircraft noise reduction have been developed by NASA over the past 15 years through the Advanced Subsonic Technology (AST) Noise Reduction Program and the Quiet Aircraft Technology (QAT) project. This presentation summarizes highlights from these programs and anticipated noise reduction benefits for communities surrounding airports. Historical progress in noise reduction and technologies available for future aircraft/engine development are identified. Technologies address aircraft/engine components including fans, exhaust nozzles, landing gear, and flap systems. New "chevron" nozzles have been developed and implemented on several aircraft in production today that provide significant jet noise reduction. New engines using Ultra-High Bypass (UHB) ratios are projected to provide about 10 EPNdB (Effective Perceived Noise Level in decibels) engine noise reduction relative to the average fleet that was flying in 1997. Audio files are embedded in the presentation that estimate the sound levels for a 35,000 pound thrust engine for takeoff and approach power conditions. The predictions are based on actual model scale data that was obtained by NASA. Finally, conceptual pictures are shown that look toward future aircraft/propulsion systems that might be used to obtain further noise reduction.

  9. Contamination control and plume assessment of low-energy thrusters

    NASA Technical Reports Server (NTRS)

    Scialdone, John J.

    1993-01-01

    Potential contamination of a spacecraft cryogenic surface by a xenon (Xe) ion generator was evaluated. The analysis involves the description of the plume exhausted from the generator with its relative component fluxes on the spacecraft surfaces, and verification of the conditions for condensation, adsorption, and sputtering at those locations. The data describing the plume fluxes and their effects on surfaces were obtained from two sources: the tests carried out with the Xe generator in a small vacuum chamber to indicate deposits and sputter on monitor slides; and the extensive tests with a mercury (Hg) ion thruster in a large vacuum chamber. The Hg thruster tests provided data on the neutrals, on low-energy ion fluxes, on high-energy ion fluxes, and on sputtered materials at several locations within the plume.

  10. A wide field-of-view imaging DOAS instrument for continuous trace gas mapping from aircraft

    NASA Astrophysics Data System (ADS)

    Schönhardt, A.; Altube, P.; Gerilowski, K.; Krautwurst, S.; Hartmann, J.; Meier, A. C.; Richter, A.; Burrows, J. P.

    2014-04-01

    For the purpose of trace gas measurements and pollution mapping, the Airborne imaging DOAS instrument for Measurements of Atmospheric Pollution (AirMAP) has been developed, characterised and successfully operated from aircraft. From the observations with the AirMAP instrument nitrogen dioxide (NO2) columns were retrieved. A major benefit of the pushbroom imaging instrument is the spatially continuous, gap-free measurement sequence independent of flight altitude, a valuable characteristic for mapping purposes. This is made possible by the use of a frame-transfer detector. With a wide-angle entrance objective, a broad field-of-view across track of around 48° is achieved, leading to a swath width of about the same size as the flight altitude. The use of fibre coupled light intake optics with sorted light fibres allows flexible positioning within the aircraft and retains the very good imaging capabilities. The measurements yield ground spatial resolutions below 100 m. From a maximum of 35 individual viewing directions (lines of sight, LOS) represented by 35 single fibres, the number of viewing directions is adapted to each situation by averaging according to signal-to-noise or spatial resolution requirements. Exploitation of all the viewing directions yields observations at 30 m spatial resolution, making the instrument a suitable tool for mapping trace gas point sources and small scale variability. For accurate spatial mapping the position and aircraft attitude are taken into account using the Attitude and Heading Reference System of the aircraft. A first demonstration mission using AirMAP was undertaken. In June 2011, AirMAP has been operated on the AWI Polar-5 aircraft in the framework of the AIRMETH2011 campaign. During a flight above a medium sized coal-fired power plant in North-West Germany, AirMAP clearly detects the emission plume downwind from the exhaust stack, with NO2 vertical columns around 2 × 1016 molecules cm-2 in the plume center. The emission

  11. Research needs in aircraft noise prediction

    NASA Technical Reports Server (NTRS)

    Raney, J. P.

    1975-01-01

    Progress needed in understanding the mechanisms of aircraft noise generation and propagation is outlined using the focus provided by the need to predict accurately the noise produced and received at the ground by an aircraft operating in the vicinity of an airport. The components of internal engine noise generation, jet exhaust, airframe noise and shielding and configuration effects, and the roles of atmospheric propagation and ground noise attenuation are presented and related to the prediction problem. The role of NASA in providing the focus and direction for needed advances is discussed, and possible contributions of the academic community in helping to fulfill the needs for accurate aircraft noise prediction methods are suggested.

  12. Rocket plume temperature measurement by wire welded thermocouples

    NASA Astrophysics Data System (ADS)

    Xu, Qiang

    2006-05-01

    The plume of solid rocket motor is a high velocity flow with high temperature. Temperature distribution in the plume is of great interest for analyzing the compatibility of rocket weapon system. The high temperature exhausted flow field would cause damage on certain equipment and loading vehicles. An instantaneous temperature field with sharp step is established by the exhausted flow field of rocket motor. The increasing rate of the step depends on the flow velocity at cross section of nozzle exit. To perform an accurate measurement of temperature inside the flow field, a thermocouple must be sturdy enough to endure the flow impingement. In the meantime, the thermocouple must have a short time constant to trace the temperature fluctuation in flow field and a small size to avoid disturbing the flow field severely. The dynamic performance of the thermocouples used in exhausted flow temperature measurement must be evaluated before the experiment. The thermocouple which can be used in measuring the temperature distribution in rocket plume was presented in this paper. A NAMNAC (R) self-renew-erode thermocouples with a nominal time constant of 10 microseconds was used as a reference in a dynamic calibration test for this kind of thermocouple. The thermocouple could trace the temperature increase in the exhausted flow perfectly. This kind of thermocouples was used in several real tests of rocket motors, such as the temperature in free exhausted flow field of a stationary rocket motor test, the stagnate temperature in a shock flow field during the launching of a rocket, and the temperature in a launch tube.

  13. Hydrostatic Modeling of Buoyant Plumes

    NASA Astrophysics Data System (ADS)

    Stroman, A.; Dewar, W. K.; Wienders, N.; Deremble, B.

    2014-12-01

    The Deepwater Horizon oil spill in the Gulf of Mexico has led to increased interest in understanding point source convection dynamics. Most of the existing oil plume models use a Lagrangian based approach, which computes integral measures such as plume centerline trajectory and plume radius. However, this approach doesn't account for feedbacks of the buoyant plume on the ambient environment. Instead, we employ an Eulerian based approach to acquire a better understanding of the dynamics of buoyant plumes. We have performed a series of hydrostatic modeling simulations using the MITgcm. Our results show that there is a dynamical response caused by the presence of the buoyant plume, in that there is a modification of the background flow. We find that the buoyant plume becomes baroclinically unstable and sheds eddies at the neutral buoyancy layer. We also explore different scenarios to determine the effect of the buoyancy source and the temperature stratification on the evolution of buoyant plumes.

  14. LAMP Observes the LCROSS Plume

    NASA Video Gallery

    This video shows LAMP’s view of the LCROSS plume. The first half of the animation shows the LAMP viewport scanning across the horizon, passing through the plume, and moving on. The second half of...

  15. In situ observations and model calculations of black carbon emission by aircraft at cruise altitude

    NASA Astrophysics Data System (ADS)

    Petzold, A.; DöPelheuer, A.; Brock, C. A.; Schröder, F.

    1999-09-01

    The exhaust aerosol of two aircraft at cruise was extensively characterized in the size range from 0.003 to 2 μm for plume ages ≤2 s. The black carbon (BC) exhaust aerosol of an older technology engine (Rolls-Royce/Snecma M45H Mk501) consisted of a primary BC mode with a modal diameter of 0.035 μm and a mode of coagulated BC particles with a peak near 0.15-0.16 μm in diameter. The total number density at the nozzle exit plane was 3×107 cm-3. In contrast, a modern technology engine (CFM International CFM56-3B1) emitted far smaller BC particles with a primary mode at 0.025 μm and a coagulated mode at 0.15 μm, as well as fewer particles by number with a concentration of 9×106 cm-3. The single-scattering albedo of the jet exhaust aerosol was 0.035 ± 0.02 inside the plume, indicating a dominant contribution of ultrafine (D<0.1 μm) BC particles to light extinction. Black carbon number emission indices EI(N) varied from 3.5×1014 (CFM56-3B1) to 1.7×1015 kg-1 (M45H Mk501) with corresponding mass emission indices EI(BC) of 0.011 and 0.1 g kg-1. Previously reported corresponding values for a CF6-80C2A2 engine were 6×1014 kg-1 and 0.023 g kg-1, respectively. A comparison between EI(BC) values calculated by a new correlation method and measured data shows an excellent agreement, with deviations <10% at cruise conditions. By extending the EI(BC) calculation method to a globally operating aircraft fleet, a fleet-averaged emission index EI(BC) = 0.038 g kg-1 is calculated.

  16. Atmospheric scavenging exhaust

    NASA Technical Reports Server (NTRS)

    Fenton, D. L.; Purcell, R. Y.

    1977-01-01

    Solid propellant rocket exhaust was directly utilized to ascertain raindrop scavenging rates for hydrogen chloride. The airborne HCl concentration varied from 0.2 to 10.0 ppm and the raindrop sizes tested included 0.55 mm, 1.1 mm, and 3.0 mm. Two chambers were used to conduct the experiments. A large, rigid walled, spherical chamber stored the exhaust constituents while the smaller chamber housing all the experiments was charged as required with rocket exhaust HCl. Surface uptake experiments demonstrated an HCl concentration dependence for distilled water. Sea water and brackish water HCl uptake was below the detection limit of the chlorine-ion analysis technique employed. Plant life HCl uptake experiments were limited to corn and soybeans. Plant age effectively correlated the HCl uptake data. Metallic corrosion was not significant for single 20 minute exposures to the exhaust HCl under varying relative humidity.

  17. An Experimental Investigation of Rectangular Exhaust-Gas Ejectors Applicable for Engine Cooling

    NASA Technical Reports Server (NTRS)

    Manganiello, Eugene J; Bogatsky, Donald

    1945-01-01

    An experimental investigation of rectangular exhaust-gas ejector pumps was conducted to provide data that would serve as a guide to the design of ejector applications for aircraft engines with marginal cooling. The pumping characteristics of rectangular ejectors actuated by the exhaust of a single-cylinder aircraft engine were determined for a range of ejector mixing-section area from 20 to 50 square inches, over-all length from 12 to 42 inches, aspect ratio from 1 to 5, diffusing exit area from 20 to 81 square inches, and exhaust-nozzle aspect ratio from 1 to 42.

  18. Evaluation of Visible Plumes.

    ERIC Educational Resources Information Center

    Brennan, Thomas

    Developed for presentation at the 12th Conference on Methods in Air Pollution and Industrial Hygiene Studies, University of Southern California, April, 1971, this outline discusses plumes with contaminants that are visible to the naked eye. Information covers: (1) history of air pollution control regulations, (2) need for methods of evaluating…

  19. COLD WEATHER PLUME STUDY

    EPA Science Inventory

    While many studies of power plant plume transport and transformation have been performed during the summer, few studies of these processes during the winter have been carried out. Accordingly, the U.S. Environmental Protection Agency and the Electric Power Research Institute join...

  20. Improving operational plume forecasts

    NASA Astrophysics Data System (ADS)

    Balcerak, Ernie

    2012-04-01

    Forecasting how plumes of particles, such as radioactive particles from a nuclear disaster, will be transported and dispersed in the atmosphere is an important but computationally challenging task. During the Fukushima nuclear disaster in Japan, operational plume forecasts were produced each day, but as the emissions continued, previous emissions were not included in the simulations used for forecasts because it became impractical to rerun the simulations each day from the beginning of the accident. Draxler and Rolph examine whether it is possible to improve plume simulation speed and flexibility as conditions and input data change. The authors use a method known as a transfer coefficient matrix approach that allows them to simulate many radionuclides using only a few generic species for the computation. Their simulations work faster by dividing the computation into separate independent segments in such a way that the most computationally time consuming pieces of the calculation need to be done only once. This makes it possible to provide real-time operational plume forecasts by continuously updating the previous simulations as new data become available. They tested their method using data from the Fukushima incident to show that it performed well. (Journal of Geophysical Research-Atmospheres, doi:10.1029/2011JD017205, 2012)

  1. PLUME and research sotware

    NASA Astrophysics Data System (ADS)

    Baudin, Veronique; Gomez-Diaz, Teresa

    2013-04-01

    The PLUME open platform (https://www.projet-plume.org) has as first goal to share competences and to value the knowledge of software experts within the French higher education and research communities. The project proposes in its platform the access to more than 380 index cards describing useful and economic software for this community, with open access to everybody. The second goal of PLUME focuses on to improve the visibility of software produced by research laboratories within the higher education and research communities. The "development-ESR" index cards briefly describe the main features of the software, including references to research publications associated to it. The platform counts more than 300 cards describing research software, where 89 cards have an English version. In this talk we describe the theme classification and the taxonomy of the index cards and the evolution with new themes added to the project. We will also focus on the organisation of PLUME as an open project and its interests in the promotion of free/open source software from and for research, contributing to the creation of a community of shared knowledge.

  2. Enceladus' Water Vapour Plumes

    NASA Technical Reports Server (NTRS)

    Hansen, Candice J.; Esposito, L.; Colwell, J.; Hendrix, A.; Matson, Dennis; Parkinson, C.; Pryor, W.; Shemansky, D.; Stewart, I.; Tew, J.; Yung, Y.

    2006-01-01

    A viewgraph presentation on the discovery of Enceladus water vapor plumes is shown. Conservative modeling of this water vapor is also presented and also shows that Enceladus is the source of most of the water required to supply the neutrals in Saturn's system and resupply the E-ring against losses.

  3. Buoyant plume calculations

    SciTech Connect

    Penner, J.E.; Haselman, L.C.; Edwards, L.L.

    1985-01-01

    Smoke from raging fires produced in the aftermath of a major nuclear exchange has been predicted to cause large decreases in surface temperatures. However, the extent of the decrease and even the sign of the temperature change, depend on how the smoke is distributed with altitude. We present a model capable of evaluating the initial distribution of lofted smoke above a massive fire. Calculations are shown for a two-dimensional slab version of the model and a full three-dimensional version. The model has been evaluated by simulating smoke heights for the Hamburg firestorm of 1943 and a smaller scale oil fire which occurred in Long Beach in 1958. Our plume heights for these fires are compared to those predicted by the classical Morton-Taylor-Turner theory for weakly buoyant plumes. We consider the effect of the added buoyancy caused by condensation of water-laden ground level air being carried to high altitude with the convection column as well as the effects of background wind on the calculated smoke plume heights for several fire intensities. We find that the rise height of the plume depends on the assumed background atmospheric conditions as well as the fire intensity. Little smoke is injected into the stratosphere unless the fire is unusually intense, or atmospheric conditions are more unstable than we have assumed. For intense fires significant amounts of water vapor are condensed raising the possibility of early scavenging of smoke particles by precipitation. 26 references, 11 figures.

  4. Modeling the Complex Photochemistry of Biomass Burning Plumes in Plume-Scale, Regional, and Global Air Quality Models

    NASA Astrophysics Data System (ADS)

    Alvarado, M. J.; Lonsdale, C. R.; Yokelson, R. J.; Travis, K.; Fischer, E. V.; Lin, J. C.

    2014-12-01

    Forecasting the impacts of biomass burning (BB) plumes on air quality is difficult due to the complex photochemistry that takes place in the concentrated young BB plumes. The spatial grid of global and regional scale Eulerian models is generally too large to resolve BB photochemistry, which can lead to errors in predicting the formation of secondary organic aerosol (SOA) and O3, as well as the partitioning of NOyspecies. AER's Aerosol Simulation Program (ASP v2.1) can be used within plume-scale Lagrangian models to simulate this complex photochemistry. We will present results of validation studies of the ASP model against aircraft observations of young BB smoke plumes. We will also present initial results from the coupling of ASP v2.1 into the Lagrangian particle dispersion model STILT-Chem in order to better examine the interactions between BB plume chemistry and dispersion. In addition, we have used ASP to develop a sub-grid scale parameterization of the near-source chemistry of BB plumes for use in regional and global air quality models. The parameterization takes inputs from the host model, such as solar zenith angle, temperature, and fire fuel type, and calculates enhancement ratios of O3, NOx, PAN, aerosol nitrate, and other NOy species, as well as organic aerosol (OA). We will present results from the ASP-based BB parameterization as well as its implementation into the global atmospheric composition model GEOS-Chem for the SEAC4RS campaign.

  5. Turbulence modeling of free shear layers for high-performance aircraft

    NASA Technical Reports Server (NTRS)

    Sondak, Douglas L.

    1993-01-01

    The High Performance Aircraft (HPA) Grand Challenge of the High Performance Computing and Communications (HPCC) program involves the computation of the flow over a high performance aircraft. A variety of free shear layers, including mixing layers over cavities, impinging jets, blown flaps, and exhaust plumes, may be encountered in such flowfields. Since these free shear layers are usually turbulent, appropriate turbulence models must be utilized in computations in order to accurately simulate these flow features. The HPCC program is relying heavily on parallel computers. A Navier-Stokes solver (POVERFLOW) utilizing the Baldwin-Lomax algebraic turbulence model was developed and tested on a 128-node Intel iPSC/860. Algebraic turbulence models run very fast, and give good results for many flowfields. For complex flowfields such as those mentioned above, however, they are often inadequate. It was therefore deemed that a two-equation turbulence model will be required for the HPA computations. The k-epsilon two-equation turbulence model was implemented on the Intel iPSC/860. Both the Chien low-Reynolds-number model and a generalized wall-function formulation were included.

  6. 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.

  7. Effects of vehicle exhaust to VLC link: measurement and analysis

    NASA Astrophysics Data System (ADS)

    Li, Zening; Lang, Tian; Liao, Linchao; Chen, Gang

    2015-09-01

    Optical beam propagation through the turbulent media such as the vehicle exhaust plumes need to be studied in order to estimate the communication performance degradations on vehicular visible light communication (V2LC) networks. When the optical transceiver is close to the exhaust plumes, the optical waves may be distorted in both phase and amplitude, by perturbations on the air's refractive index spatially and temporally. In this paper, the authors present the measurements performed on V2LC communication link using two different vehicles. In particular, several different transceiver configurations with respect to the position of exhaust nozzle have been tested and compared, and the turbulence strength is evaluated by scintillation index (SI). Since the V2LC applications are mainly based on intensity modulated, direct detection method, only the receiving optical power fluctuation (scintillation) will be discussed. Finally, the error rate performance under different log intensity variances is analyzed, demonstrating that scintillation effects introduced by the vehicle exhaust can be negligible in V2LC applications.

  8. Behavior of Mercury Emissions from a Commercial Coal-Fired Utility Boiler: TheRelationship Between Stack Speciation and Near-Field Plume Measurements

    EPA Science Inventory

    The reduction of divalent gaseous mercury (HgII) to elemental gaseous mercury (Hg0) in a commercial coal-fired power plant (CFPP)exhaust plume was investigated by simultaneous measurement in-stack and in-plume as part of a collaborative study among the U.S....

  9. Ozone production efficiency of a ship-plume: ITCT 2K2 case study.

    PubMed

    Kim, Hyun S; Kim, Yong H; Han, Kyung M; Kim, Jhoon; Song, Chul H

    2016-01-01

    Ozone production efficiency (OPE) of ship plume was first evaluated in this study, based on ship-plume photochemical/dynamic model simulations and the ship-plume composition data measured during the ITCT 2K2 (Intercontinental Transport and Chemical Transformation 2002) aircraft campaign. The averaged instantaneous OPEs (OPE(i)‾) estimated via the ship-plume photochemical/dynamic modeling for the ITCT 2K2 ship-plume ranged between 4.61 and 18.92, showing that the values vary with the extent of chemical evolution (or chemical stage) of the ship plume and the stability classes of the marine boundary layer (MBL). Together with OPE(i)‾, the equivalent OPEs (OPE(e)‾) for the entire ITCT 2K2 ship-plume were also estimated. The OPE(e)‾ values varied between 9.73 (for the stable MBL) and 12.73 (for the moderately stable MBL), which agreed well with the OPE(e)‾ of 12.85 estimated based on the ITCT 2K2 ship-plume observations. It was also found that both the model-simulated and observation-based OPE(e)‾ inside the ship-plume were 0.29-0.38 times smaller than the OPE(e)‾ calculated/measured outside the ITCT 2K2 ship-plume. Such low OPEs insides the ship plume were due to the high levels of NO and non-liner ship-plume photochemistry. Possible implications of this ship-plume OPE study in the global chemistry-transport modeling are also discussed. PMID:26009472

  10. A Method for Reducing the Temperature of Exhaust Manifolds

    NASA Technical Reports Server (NTRS)

    Schey, Oscar W; Young, Alfred W

    1931-01-01

    This report describes tests conducted at the Langley Memorial Aeronautical Laboratory on an "air-inducting" exhaust manifold for aircraft engines. The exhaust gases from each cylinder port are discharged into the throat of an exhaust pipe which has a frontal bellmouth. Cooling air is drawn into the pipe, where it surrounds and mixes with the exhaust gases. Temperatures of the manifold shell and of the exhaust gases were obtained in flight for both a conventional manifold and the air-inducting manifold. The air-inducting manifold was installed on an engine which was placed on a test stand. Different fuels were sprayed on and into the manifold to determine whether the use of this manifold reduced the fire hazard. The flight tests showed reductions in manifold temperatures of several hundred degrees, to values below the ignition point of aviation gasoline. On the test stand when the engine was run at idling speeds fuels sprayed into the manifold ignited. It is believed that at low engine speeds the fuel remained in the manifold long enough to become thoroughly heated, and was then ignited by the exhaust gas which had not mixed with cooling air. The use of the air-inducting exhaust manifold must reduce the fire hazard by virtue of its lower operating temperature, but it is not a completely satisfactory solution of the problem.

  11. Chemical plume source localization.

    PubMed

    Pang, Shuo; Farrell, Jay A

    2006-10-01

    This paper addresses the problem of estimating a likelihood map for the location of the source of a chemical plume using an autonomous vehicle as a sensor probe in a fluid flow. The fluid flow is assumed to have a high Reynolds number. Therefore, the dispersion of the chemical is dominated by turbulence, resulting in an intermittent chemical signal. The vehicle is capable of detecting above-threshold chemical concentration and sensing the fluid flow velocity at the vehicle location. This paper reviews instances of biological plume tracing and reviews previous strategies for a vehicle-based plume tracing. The main contribution is a new source-likelihood mapping approach based on Bayesian inference methods. Using this Bayesian methodology, the source-likelihood map is propagated through time and updated in response to both detection and nondetection events. Examples are included that use data from in-water testing to compare the mapping approach derived herein with the map derived using a previously existing technique. PMID:17036813

  12. The exhausted horse syndrome.

    PubMed

    Foreman, J H

    1998-04-01

    Exhaustion occurs in most equestrian sports, but it is more frequent in events that require sustained endurance work such as endurance racing, three-day eventing, trial riding, and hunting. Exhaustion is also more likely when an unfit, unacclimatized, or unsound horse is exercised. Mechanisms that contribute to exhaustion include heat retention, fluid and electrolyte loss, acid-base imbalance, and intramuscular glycogen depletion. Clinical signs include elevated temperature, pulse, and respiratory rate; depression; anorexia; unwillingness to continue to exercise; dehydration; weakness; stiffness; hypovolemic shock; exertional myopathy; synchronous diaphragmatic flutter; atrial fibrillation; diarrhea; colic; and laminitis. Treatment includes stopping exercise; rapid cooling; rapid large volume intravenous or oral fluid administration; and nonsteroidal anti-inflammatory drug administration. PMID:9561696

  13. Hyperventilation and exhaustion syndrome.

    PubMed

    Ristiniemi, Heli; Perski, Aleksander; Lyskov, Eugene; Emtner, Margareta

    2014-12-01

    Chronic stress is among the most common diagnoses in Sweden, most commonly in the form of exhaustion syndrome (ICD-10 classification - F43.8). The majority of patients with this syndrome also have disturbed breathing (hyperventilation). The aim of this study was to investigate the association between hyperventilation and exhaustion syndrome. Thirty patients with exhaustion syndrome and 14 healthy subjects were evaluated with the Nijmegen Symptom Questionnaire (NQ). The participants completed questionnaires about exhaustion, mental state, sleep disturbance, pain and quality of life. The evaluation was repeated 4 weeks later, after half of the patients and healthy subjects had engaged in a therapy method called 'Grounding', a physical exercise inspired by African dance. The patients reported significantly higher levels of hyperventilation as compared to the healthy subjects. All patients' average score on NQ was 26.57 ± 10.98, while that of the healthy subjects was 15.14 ± 7.89 (t = -3.48, df = 42, p < 0.001). The NQ scores correlated strongly with two measures of exhaustion (Karolinska Exhaustion Scale KES r = 0.772, p < 0.01; Shirom Melamed Burnout Measure SMBM r = 0.565, p < 0.01), mental status [Hospital Anxiety and Depression Score (HADS) depression r = 0.414, p < 0.01; HADS anxiety r = 0.627, p < 0.01], sleep disturbances (r = -0.514, p < 0.01), pain (r = -.370, p < 0.05) and poor well-being (Medical Outcomes Survey Short Form 36 questionnaire- SR Health r = -0.529, p < 0.05). In the logistic regression analysis, the variance in the scores from NQ were explained to a high degree (R(2) = 0.752) by scores in KES and HADS. The brief Grounding training contributed to a near significant reduction in hyperventilation (F = 2.521, p < 0.124) and to significant reductions in exhaustion scores and scores of depression and anxiety. The conclusion is that hyperventilation is common in exhaustion syndrome patients and that it can be reduced by systematic physical therapy

  14. 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 ...

  15. The 1979 Southeastern Virginia Urban Plume Study (SEV-UPS): Surface and airborne studies

    NASA Technical Reports Server (NTRS)

    White, J. H.; Eaton, W. C.; Saeger, M. L.; Strong, R. B.; Tommerdahl, J. B.

    1980-01-01

    The operation of two surface monitoring stations (one in downtown Norfolk, Virginia, one south of the city near the Great Dismal Swamp) and the collection of 40 hours of airborne measurements is described. Surface site measurements of ozone, oxides of nitrogen, sulfur dioxide, temperature, dew point, b sub seat, and condensation nuclei were made. Instrument calibrations, quality assurance audits, and preliminary data analysis in support of the Urban Plume Study were also made. The air pollution problems that were addressed are discussed. Data handling procedures followed for the surface stations are presented. The operation of the aircraft sampling platform is described. Aircraft sampling procedures are discussed. A preliminary descriptive analysis of the aircraft data is given along with data or plots for surface sites, airborne studies, hydrocarbon species, and instrument performance audits. Several of the aircraft flights clearly show the presence of an urban ozone plume downwind of Norfolk in the direction of the mean wind flow.

  16. Delta 2 Explosion Plume Analysis Report

    NASA Technical Reports Server (NTRS)

    Evans, Randolph J.

    2000-01-01

    A Delta II rocket exploded seconds after liftoff from Cape Canaveral Air Force Station (CCAFS) on 17 January 1997. The cloud produced by the explosion provided an opportunity to evaluate the models which are used to track potentially toxic dispersing plumes and clouds at CCAFS. The primary goal of this project was to conduct a case study of the dispersing cloud and the models used to predict the dispersion resulting from the explosion. The case study was conducted by comparing mesoscale and dispersion model results with available meteorological and plume observations. This study was funded by KSC under Applied Meteorology Unit (AMU) option hours. The models used in the study are part of the Eastern Range Dispersion Assessment System (ERDAS) and include the Regional Atmospheric Modeling System (RAMS), HYbrid Particle And Concentration Transport (HYPACT), and Rocket Exhaust Effluent Dispersion Model (REEDM). The primary observations used for explosion cloud verification of the study were from the National Weather Service's Weather Surveillance Radar 1988-Doppler (WSR-88D). Radar reflectivity measurements of the resulting cloud provided good estimates of the location and dimensions of the cloud over a four-hour period after the explosion. The results indicated that RAMS and HYPACT models performed reasonably well. Future upgrades to ERDAS are recommended.

  17. Measuring Wildfires From Aircraft And Satellites

    NASA Technical Reports Server (NTRS)

    Brass, J. A.; Arvesen, J. C.; Ambrosia, V. G.; Riggan, P. J.; Meyers, J. S.

    1991-01-01

    Aircraft and satellite systems yield wide-area views, providing total coverage of affected areas. System developed for use aboard aircraft includes digital scanner that records data in 12 channels. Transmits data to ground station for immediate use in fighting fires. Enables researchers to estimate gaseous and particulate emissions from fires. Provides information on temperatures of flame fronts and soils, intensities and rate of spread of fires, characteristics of fuels and smoke plumes, energy-release rates, and concentrations and movements of trace gases. Data relates to heating and cooling of soils, loss of nutrients, and effects on atmospheric, terrestrial, and aquatic systems.

  18. STOL Aircraft

    NASA Technical Reports Server (NTRS)

    1988-01-01

    Michael E. Fisher, President of AeroVisions International, has introduced the Culex light twin engine aircraft which offers economy of operation of a single engine plane, the ability to fly well on one engine, plus the capability of flying from short, unimproved fields of takeoff and landing distances less than 35 feet. Key element of design is an airfoil developed by Langley. Culex was originally intended to be factory built aircraft for special utility markets. However, it is now offered as a build-it-yourself kit plane.

  19. Incoherent scatter from space shuttle and rocket engine plumes in the ionosphere

    NASA Astrophysics Data System (ADS)

    Bernhardt, P. A.; Huba, J. D.; Swartz, W. E.; Kelley, M. C.

    1998-02-01

    Enhanced echoes from the 430 MHz radar at Arecibo were observed during burns of the space shuttle orbital maneuver subsystem (OMS) engines near 317 km altitude. Similar radar signatures of enhanced backscatter were also obtained by the Millstone Hill radar observing the plume of a Centaur engine burning in the ionosphere. A theoretical model of incoherent scatter is presented to explain the radar backscatter observations. The theory considers molecular ion beams generated in the exhaust plume as a result of charge exchange between the ambient O+ ions and the high-speed exhaust molecules (primarily H2O). The field-aligned gyromotion of the pickup ions affects the radio wave scattering from the random thermal fluctuations of electron density. Numerical calculations are carried out for plasmas modified by the space shuttle or Centaur engines, and reasonable agreement with observations is found for the total scattered power. Incoherent backscatter spectra respond to characteristics of the exhaust plume such as vector flow velocity, temperature, and composition. The nonequilibrium velocity distributions for the ions in the pickup ion plume are similar to the distributions found in strongly convecting auroral region ionospheres. The incoherent scatter from the plume ions can be used to validate techniques used to study naturally disturbed plasmas. The predictions of our radar scatter calculations will be tested in future experiments using the space shuttle OMS engines over incoherent scatter radars located at equatorial latitudes and midlatitudes.

  20. Empirical Scaling Laws of Rocket Exhaust Cratering

    NASA Technical Reports Server (NTRS)

    Donahue, Carly M.; Metzger, Philip T.; Immer, Christopher D.

    2005-01-01

    When launching or landing a space craft on the regolith of a terrestrial surface, special attention needs to be paid to the rocket exhaust cratering effects. If the effects are not controlled, the rocket cratering could damage the spacecraft or other surrounding hardware. The cratering effects of a rocket landing on a planet's surface are not understood well, especially for the lunar case with the plume expanding in vacuum. As a result, the blast effects cannot be estimated sufficiently using analytical theories. It is necessary to develop physics-based simulation tools in order to calculate mission-essential parameters. In this work we test out the scaling laws of the physics in regard to growth rate of the crater depth. This will provide the physical insight necessary to begin the physics-based modeling.

  1. Exhaust bypass flow control for exhaust heat recovery

    SciTech Connect

    Reynolds, Michael G.

    2015-09-22

    An exhaust system for an engine comprises an exhaust heat recovery apparatus configured to receive exhaust gas from the engine and comprises a first flow passage in fluid communication with the exhaust gas and a second flow passage in fluid communication with the exhaust gas. A heat exchanger/energy recovery unit is disposed in the second flow passage and has a working fluid circulating therethrough for exchange of heat from the exhaust gas to the working fluid. A control valve is disposed downstream of the first and the second flow passages in a low temperature region of the exhaust heat recovery apparatus to direct exhaust gas through the first flow passage or the second flow passage.

  2. Nighttime NOx Chemistry in Coal-Fired Power Plant Plumes

    NASA Astrophysics Data System (ADS)

    Fibiger, D. L.; McDuffie, E. E.; Dube, W. P.; Veres, P. R.; Lopez-Hilfiker, F.; Lee, B. H.; Green, J. R.; Fiddler, M. N.; Ebben, C. J.; Sparks, T.; Weinheimer, A. J.; Montzka, D.; Campos, T. L.; Cohen, R. C.; Bililign, S.; Holloway, J. S.; Thornton, J. A.; Brown, S. S.

    2015-12-01

    Nitrogen oxides (NOx = NO + NO2) play a key role in atmospheric chemistry. During the day, they catalyze ozone (O3) production, while at night they can react to form nitric acid (HNO3) and nitryl chloride (ClNO2) and remove O3 from the atmosphere. These processes are well studied in the summer, but winter measurements are more limited. Coal-fired power plants are a major source of NOx to the atmosphere, making up approximately 30% of emissions in the US (epa.gov). NOx emissions can vary seasonally, as well as plant-to-plant, with important impacts on the details of the plume chemistry. In particular, due to inefficient plume dispersion, nighttime NOx emissions from power plants are held in concentrated plumes, where rates of mixing with ambient O3 have a strong influence on plume evolution. We will show results from the aircraft-based WINTER campaign over the northeastern United States, where several nighttime intercepts of power plant plumes were made. Several of these intercepts show complete O3 titration, which can have a large influence on NOx lifetime, and thus O3 production, in the plume. When power plant NO emissions exceed background O3 levels, O3 is completely consumed converting NO to NO2. In the presence of O3, NO2 will be oxidized to NO3, which will then react with NO2 to form N2O5, which can then form HNO3 and/or ClNO2 and, ultimately, remove NOx from the atmosphere or provide next-day oxidant sources. If there is no O3 present, however, no further chemistry can occur and NO and NO2 will be transported until mixing with sufficient O3 for higher oxidation products. Modeling results of plume development and mixing, which can tell us more about this transport, will also be presented.

  3. Hybrid Exhaust Component

    NASA Technical Reports Server (NTRS)

    Pelletier, Gerard D. (Inventor); Logan, Charles P. (Inventor); McEnerney, Bryan William (Inventor); Haynes, Jeffrey D. (Inventor)

    2015-01-01

    An exhaust includes a wall that has a first composite material having a first coefficient of thermal expansion and a second composite material having a second coefficient of the thermal expansion that is less than the first coefficient of thermal expansion.

  4. Diesel engine exhaust

    Integrated Risk Information System (IRIS)

    Diesel engine exhaust ; CASRN N.A . Human health assessment information on a chemical substance is included in the IRIS database only after a comprehensive review of toxicity data , as outlined in the IRIS assessment development process . Sections I ( Health Hazard Assessments for Noncarcinogenic Ef

  5. Patos Lagoon outflow within the Río de la Plata plume using an airborne salinity mapper: Observing an embedded plume

    NASA Astrophysics Data System (ADS)

    Burrage, Derek; Wesson, Joel; Martinez, Carlos; Pérez, Tabare; Möller, Osmar, Jr.; Piola, Alberto

    2008-07-01

    Major river systems discharging into continental shelf waters frequently form buoyant coastal currents that propagate along the continental shelf in the direction of coastal trapped wave propagation (with the coast on the right/left, in the northern/southern hemisphere). The combined flow of the Uruguay and Paraná Rivers, which discharges freshwater into the Río de la Plata estuary (Lat. ˜36°S), often gives rise to a buoyant coastal current (the 'Plata plume') that extends northward along the continental shelf off Uruguay and Southern Brazil. Depending upon the prevailing rainfall, wind and tidal conditions, the Patos/Mirim Lagoon complex (Lat. ˜32°S) may also produce a freshwater outflow plume that expands across the inner continental shelf. Under these circumstances the Patos outflow plume can be embedded in temperature, salinity and current fields that are strongly influenced by the larger Plata plume. The purpose of this paper is to present observations of such an embedded plume structure and to determine the dynamical characteristics of the ambient and embedded plumes. We describe selected results of coincident airborne remote sensing and shipboard in-situ surveys of the salinity distribution and extent of the Plata and Patos/Mirim Lagoon plumes conducted under contrasting winter (2003) and summer (2004) conditions. The surveys were carried out in the context of a comprehensive multi-disciplinary study of the Plata plume and its response to prevailing seasonal weather conditions. The objective was to map the surface salinity distribution of the Plata plume at synoptic scales under representative winter and summer conditions. Additionally, the airborne survey included finer-scale mapping of specific features including the Río de Plata estuarine front and the Patos Lagoon plume, with the objective of determining the distribution and behavior of the plumes in the estuaries and on the continental shelf. The airborne survey was conducted with an aircraft

  6. Seismic Imaging of Mantle Plumes

    NASA Astrophysics Data System (ADS)

    Nataf, Henri-Claude

    The mantle plume hypothesis was proposed thirty years ago by Jason Morgan to explain hotspot volcanoes such as Hawaii. A thermal diapir (or plume) rises from the thermal boundary layer at the base of the mantle and produces a chain of volcanoes as a plate moves on top of it. The idea is very attractive, but direct evidence for actual plumes is weak, and many questions remain unanswered. With the great improvement of seismic imagery in the past ten years, new prospects have arisen. Mantle plumes are expected to be rather narrow, and their detection by seismic techniques requires specific developments as well as dedicated field experiments. Regional travel-time tomography has provided good evidence for plumes in the upper mantle beneath a few hotspots (Yellowstone, Massif Central, Iceland). Beneath Hawaii and Iceland, the plume can be detected in the transition zone because it deflects the seismic discontinuities at 410 and 660 km depths. In the lower mantle, plumes are very difficult to detect, so specific methods have been worked out for this purpose. There are hints of a plume beneath the weak Bowie hotspot, as well as intriguing observations for Hawaii. Beneath Iceland, high-resolution tomography has just revealed a wide and meandering plume-like structure extending from the core-mantle boundary up to the surface. Among the many phenomena that seem to take place in the lowermost mantle (or D''), there are also signs there of the presence of plumes. In this article I review the main results obtained so far from these studies and discuss their implications for plume dynamics. Seismic imaging of mantle plumes is still in its infancy but should soon become a turbulent teenager.

  7. 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.

  8. Axisymmetric computational fluid dynamics analysis of a film/dump-cooled rocket nozzle plume

    NASA Technical Reports Server (NTRS)

    Tucker, P. K.; Warsi, S. A.

    1993-01-01

    Prediction of convective base heating rates for a new launch vehicle presents significant challenges to analysts concerned with base environments. The present effort seeks to augment classical base heating scaling techniques via a detailed investigation of the exhaust plume shear layer of a single H2/O2 Space Transportation Main Engine (STME). Use of fuel-rich turbine exhaust to cool the STME nozzle presented concerns regarding potential recirculation of these gases to the base region with attendant increase in the base heating rate. A pressure-based full Navier-Stokes computational fluid dynamics (CFD) code with finite rate chemistry is used to predict plumes for vehicle altitudes of 10 kft and 50 kft. Levels of combustible species within the plume shear layers are calculated in order to assess assumptions made in the base heating analysis.

  9. Axisymmetric computational fluid dynamics analysis of a film/dump-cooled rocket nozzle plume

    NASA Astrophysics Data System (ADS)

    Tucker, P. K.; Warsi, S. A.

    1993-06-01

    Prediction of convective base heating rates for a new launch vehicle presents significant challenges to analysts concerned with base environments. The present effort seeks to augment classical base heating scaling techniques via a detailed investigation of the exhaust plume shear layer of a single H2/O2 Space Transportation Main Engine (STME). Use of fuel-rich turbine exhaust to cool the STME nozzle presented concerns regarding potential recirculation of these gases to the base region with attendant increase in the base heating rate. A pressure-based full Navier-Stokes computational fluid dynamics (CFD) code with finite rate chemistry is used to predict plumes for vehicle altitudes of 10 kft and 50 kft. Levels of combustible species within the plume shear layers are calculated in order to assess assumptions made in the base heating analysis.

  10. Emissions of Black Carbon Particles in Anthropogenic and Biomass Plumes over California during CARB 2008

    NASA Astrophysics Data System (ADS)

    Sahu, L. K.; Kondo, Y.; Moteki, N.; Takegawa, N.; Zhao, Y.; Vay, S. A.; Diskin, G. S.; Wisthaler, A.; Huey, L. G.

    2009-12-01

    Measurements of black carbon (BC) and other chemical species were made from the NASA DC-8 aircraft during the CARB campaign conducted over California in June 2008. We operated an SP2 system that measured BC and scattering particles. The vertical profiles of BC and scattering particles show enhancements in the lower troposphere. We have used relations of CO-CH3CN-SO2 to identify the sources of major plumes. The plumes originating from anthropogenic activities, mainly due to the use of fossil fuels (FF), were observed near the surface. However, the influence of smoke plumes from wild fire or biomass-burning (BB) sources was observed up to 3 km. Overall, the 1-minute average BC mass concentrations were in the ranges of about 90-500 ng/m3 and 300-700 ng/m3 in FF and BB plumes, respectively. The shell/core diameter ratios were much lagerer in BB plumes than those in FF plumes. Namely, the median shell/core ratios were 1.2-1.4 for FF plumes, while they were 1.4-1.7 for BB plumes. In both FF and BB plumes, the mass-size distributions of BC were single mode lognormal. However, the mass median diameters FF plumes were considerably smaller. The BC-CO2 regression slopes were 19±9 ng m-3/ppmv and 270±90 ng m-3/ppmv for FF and BB plumes, respectively. On the other hand the regression slopes of BC-CO were about 3.3 ng m-3/ppbv in both the plumes. Conversely, the regression slopes of BC with other co-emitted combustions products can be used to estimate the contributions of emissions from different sources.

  11. DIRECT MEASUREMENT OF MERCURY REACTIONS IN COAL POWER PLANT PLUMES

    SciTech Connect

    Leonard Levin

    2006-06-01

    -September 5, 2003. The experimental site was the Pleasant Prairie Power Plant in Pleasant Prairie, Wisconsin, just west of Kenosha. The experiment involved using an aircraft to capture emissions and document chemistry changes in the plume. While using the airplane for sampling, supplemental fast-response sensors for NOx, connected to data loggers, were used to gauge entry and exit times and transect intervals through plume emissions material. The Frontier Geosciences Static Plume Dilution Chamber (SPDC) was employed simultaneously adjacent to the stack to correlate its findings with the aircraft sampling, as well as providing evaluation of the SPDC as a rapid, less costly sampler for mercury chemistry. A complementary stack plume method, the Dynamic Plume Dilution (DPD) was used in the latter portion of the experiment to measure mercury speciation to observe any mercury reduction reaction with respect to both the reaction time (5 to 30 seconds) and dilution ratio. In addition, stack sampling using the ''Ontario Hydro'' wet chemistry method and continuous mercury monitors (CMM) were used to establish the baseline chemistry in the stack. Comparisons among stack, SPDC, DPD and aircraft measurements allow establishment of whether significant chemical changes to mercury occur in the plume, and of the verisimilitude of the SPDC and DPD methods. This progress report summarizes activities during a period of results review from the stack/aircraft subcontractor, data analysis and synthesis, and preparation and presentation of preliminary results to technical and oversight meetings.

  12. Aircraft cybernetics

    NASA Technical Reports Server (NTRS)

    1977-01-01

    The use of computers for aircraft control, flight simulation, and inertial navigation is explored. The man-machine relation problem in aviation is addressed. Simple and self-adapting autopilots are described and the assets and liabilities of digital navigation techniques are assessed.

  13. Pool fires in a simulated aircraft cabin interior with ventilation

    NASA Technical Reports Server (NTRS)

    Bankston, C. P.; Back, L. H.; Cho, Y. I.; Shakkottai, P.

    1987-01-01

    Results of experiments conducted at the JPL to evaluate aircraft postcrash fire hazards are presented. The experiments were carried out in a one-third scale simulated aircraft cabin geometry to study pool fire and ventilation flow interactions. It is shown that wind-induced ventilation may significantly affect fire plume orientation, smoke transport, and heat fluxes and thus will affect subsequent fire spread and the immediate survivability of the passengers.

  14. Aircraft observations of extreme ozone concentrations near thunderstorms

    SciTech Connect

    Clarke, J.F.; Griffing, G.W.

    1985-01-01

    Anomalously large short-term ozone concentrations were observed on several occasions by aircraft during an experiment on August 5, 1980, to characterize the physical and chemical properties of the Baltimore urban plume. The ozone spikes of about 500 ppb were traversed by aircraft in less than 30 s (travel distance of less than 2 km). Analysis of these and ancillary data suggest that the ozone spikes may have resulted from ozone production by chemical reactions activated by lightning associated with thunderstorms.

  15. A wide field-of-view imaging DOAS instrument for two-dimensional trace gas mapping from aircraft

    NASA Astrophysics Data System (ADS)

    Schönhardt, A.; Altube, P.; Gerilowski, K.; Krautwurst, S.; Hartmann, J.; Meier, A. C.; Richter, A.; Burrows, J. P.

    2015-12-01

    -west Germany, AirMAP clearly detected the emission plume downwind from the exhaust stack, with NO2 vertical columns around 2 × 1016 molecules cm-2 in the plume centre. NOx emissions estimated from the AirMAP observations are consistent with reports in the European Pollutant Release and Transfer Register. Strong spatial gradients and variability in NO2 amounts across and along flight direction are observed, and small-scale enhancements of NO2 above a motorway are detected.

  16. Flow fields of low pressure vent exhausts

    NASA Technical Reports Server (NTRS)

    Scialdone, John J.

    1989-01-01

    The flow field produced by low pressure gas vents are described based on experimental data obtained from tests in a large vacuum chamber. The gas density, pressure, and flux at any location in the flow field are calculated based on the vent plume description and the knowledge of the flow rate and velocity of the venting gas. The same parameters and the column densities along a specified line of sight traversing the plume are also obtained and shown by a computer-generated graphical representation. The fields obtained with a radially scanning Pitot probe within the exhausting gas are described by a power of the cosine function, the mass rate and the distance from the exit port. The field measurements were made for gas at pressures ranging from 2 to 50 torr venting from pipe fittings with diameters of 3/16 inch to 1-1/2 inches I.D. (4.76 mm to 38.1 mm). The N(2) mass flow rates ranged from 2E-4 to 3.7E-1 g/s.

  17. Flow fields of low pressure vent exhausts

    NASA Technical Reports Server (NTRS)

    Scialdone, John J.

    1990-01-01

    The flow field produced by low pressure gas vents are described based on experimental data obtained from tests in a large vacuum chamber. The gas density, pressure, and flux at any location in the flow field are calculated based on the vent plume description and the knowledge of the flow rate and velocity of the venting gas. The same parameters and the column densities along a specified line of sight traversing the plume are also obtained and shown by a computer generated graphical representation. The fields obtained with a radically scanning Pitot probe within the exhausting gas are described by a power of the cosine function, the mass rate, and the distance from the exit port. The field measurements were made for gas at pressures ranging from 2 to 50 torr venting from pipe fittings with diameters to 3/16 to 1-1/2 inches I.D. (4.76 to 38.1 mm). The N2 mass flow rates ranged from 2E-4 to 3.7E-1 g/s.

  18. The impact of nitrogen oxides emissions from aircraft upon the atmosphere at flight altitudes—results from the aeronox project

    NASA Astrophysics Data System (ADS)

    Schumann, U.

    The AERONOX project investigated the emissions of nitrogen oxides (NO x) from aircraft engines and global air traffic at cruising altitudes, the resultant increase in NO x concentrations, and the effects on the composition of the atmosphere, in particular with respect to ozone formation in the upper troposphere and lower stratosphere. The project was structured into three subprojects: Engine exhaust emissions, physics and chemistry in the aircraft wake, and global atmospheric model simulations. A complementary program of work by aviation experts has provided detailed information on air traffic data which was combined with data on aircraft performance and emissions to produce a global emissions inventory. This summary gives an overview of the results of this project. Further details are given in the following papers of this issue and the final project report of 1995. The work resulted in improved predictive equations to determine NO x emissions at cruise conditions based on available data for aircraft/engine combinations, and NO x emission measurements on two engines in cruise conditions. This information was combined with a traffic database to provide a new global NO x emissions inventory. It was found that only minor chemical changes occur during the vortex regime of the emission plume; however, this result does not exclude the possibility of further changes in the dispersion phase. A variety of global models was set up to investigate the changes in NO x concentrations and photochemistry. Although aviation contributes only a small proportion (about 3%) of the total global NO x from all anthropogenic sources, the models show that aviation contributes a large fraction to the concentrations of NOX in the upper troposphere, in particular north of 30°N.

  19. Gas and hydrogen isotopic analyses of volcanic eruption clouds in Guatemala sampled by aircraft

    USGS Publications Warehouse

    Rose, W.I., Jr.; Cadle, R.D.; Heidt, L.E.; Friedman, I.; Lazrus, A.L.; Huebert, B.J.

    1980-01-01

    Gas samples were collected by aircraft entering volcanic eruption clouds of three Guatemalan volcanoes. Gas chromatographic analyses show higher H2 and S gas contents in ash eruption clouds and lower H2 and S gases in vaporous gas plumes. H isotopic data demonstrate lighter isotopic distribution of water vapor in ash eruption clouds than in vaporous gas plumes. Most of the H2O in the vaporous plumes is probably meteoric. The data are the first direct gas analyses of explosive eruptive clouds, and demonstrate that, in spite of atmospheric admixture, useful compositional information on eruptive gases can be obtained using aircraft. ?? 1980.

  20. D-558-2 being mounted to P2B-1S launch aircraft in hangar

    NASA Technical Reports Server (NTRS)

    1954-01-01

    during take-off and landing and in tight turns. The three aircraft gathered a great deal of data about pitch-up and the coupling of lateral (yaw) and longitudinal (pitch) motions; wing and tail loads, lift, drag, and buffeting characteristics of swept-wing aircraft at transonic and supersonic speeds; and the effects of the rocket exhaust plume on lateral dynamic stability throughout the speed range. (Plume effects were a new experience for aircraft.) The number three aircraft also gathered information about the effects of external stores (bomb shapes, drop tanks) upon the aircraft's behavior in the transonic region (roughly 0.7 to 1.3 times the speed of sound). In correlation with data from other early transonic research aircraft such as the XF-92A, this information contributed to solutions to the pitch-up problem in swept-wing aircraft. The three airplanes flew a total of 313 times--123 by the number one aircraft (Bureau No. 37973--NACA 143), 103 by the second Skyrocket (Bureau No. 37974--NACA 144), and 87 by airplane number three (Bureau No. 37975--NACA 145). Skyrocket 143 flew all but one of its missions as part of the Douglas contractor program to test the airplane's performance. NACA aircraft 143 was initially powered by a Westinghouse J-34-40 turbojet engine configured only for ground take-offs, but in 1954-55 the contractor modified it to an all-rocket air-launch capability featuring an LR8-RM-6, 4-chamber Reaction Motors engine rated at 6,000 pounds of thrust at sea level (the Navy designation for the Air Force's LR-11 used in the X-1). In this configuration, NACA research pilot John McKay flew the airplane only once for familiarization on September 17, 1956. The 123 flights of NACA 143 served to validate wind-tunnel predictions of the airplane's performance, except for the fact that the airplane experienced less drag above Mach 0.85 than the wind tunnels had indicated. NACA 144 also began its flight program with a turbojet powerplant. NACA pilots Robert A

  1. Nuclear rocket plume studies

    NASA Astrophysics Data System (ADS)

    Hastings, Daniel

    1993-05-01

    A description and detailed computational analysis of a vortex cleaning system designed to remove radioactive material from the plumes of nuclear rockets is included. The proposed system is designed to remove both particulates and radioactive gaseous material from the plume. A two part computational model is used to examine the system's ability to remove particulates, and the results indicate that under some conditions, the system can remove over 99% of the particles in the flow. Two critical parameters which govern the effectiveness of the system are identified and the information necessary to estimate cleaning efficiencies for particles of known sizes and densities is provided. A simple steady analytical solution is also developed to examine the system's ability to remove gaseous radioactive material. This analysis, while inconclusive, suggests that the swirl rates necessary to achieve useful efficiencies are too high to be achieved in any practical manner. Therefore, this system is probably not suitable for use, with gaseous radioactive material. It was concluded that the system can cause negligible specific impulse losses, though there may be a substantial mass penalty associated with its use.

  2. Overview of NASA GRCs Green Propellant Infusion Mission Thruster Testing and Plume Diagnostics

    NASA Technical Reports Server (NTRS)

    Deans, Matthew C.; Reed, Brian D.; Yim, John T.; Arrington, Lynn A.; Williams, George J.; Kojima, Jun J.; McLean, Christopher H.

    2014-01-01

    The Green Propellant Infusion Mission (GPIM) is sponsored by NASA's Space Technology Mission Directorate (STMD) Technology Demonstration Mission (TDM) office. The goal of GPIM is to advance the technology readiness level of a green propulsion system, specifically, one using the monopropellant, AF-M315E, by demonstrating ground handling, spacecraft processing, and on-orbit operations. One of the risks identified for GPIM is potential contamination of sensitive spacecraft surfaces from the effluents in the plumes of AF-M315E thrusters. NASA Glenn Research Center (GRC) is conducting activities to characterize the effects of AF-M315E plume impingement and deposition. GRC has established individual plume models of the 22-N and 1-N thrusters that will be used on the GPIM spacecraft. The models describe the pressure, temperature, density, Mach number, and species concentration of the AF-M315E thruster exhaust plumes. The models are being used to assess the impingement effects of the AF-M315E thrusters on the GPIM spacecraft. The model simulations will be correlated with plume measurement data from Laboratory and Engineering Model 22-N, AF-M315E thrusters. The thrusters will be tested in a small rocket, altitude facility at NASA GRC. The GRC thruster testing will be conducted at duty cycles representatives of the planned GPIM maneuvers. A suite of laser-based diagnostics, including Raman spectroscopy, Rayleigh spectroscopy, Schlieren imaging, and physical probes will be used to acquire plume measurements of AFM315E thrusters. Plume data will include temperature, velocity, relative density, and species concentration. The plume measurement data will be compared to the corresponding simulations of the plume model. The GRC effort will establish a data set of AF-M315E plume measurements and a plume model that can be used for future AF-M315E applications.

  3. Partially integrated exhaust manifold

    DOEpatents

    Hayman, Alan W; Baker, Rodney E

    2015-01-20

    A partially integrated manifold assembly is disclosed which improves performance, reduces cost and provides efficient packaging of engine components. The partially integrated manifold assembly includes a first leg extending from a first port and terminating at a mounting flange for an exhaust gas control valve. Multiple additional legs (depending on the total number of cylinders) are integrally formed with the cylinder head assembly and extend from the ports of the associated cylinder and terminate at an exit port flange. These additional legs are longer than the first leg such that the exit port flange is spaced apart from the mounting flange. This configuration provides increased packaging space adjacent the first leg for any valving that may be required to control the direction and destination of exhaust flow in recirculation to an EGR valve or downstream to a catalytic converter.

  4. Midwave infrared imaging Fourier transform spectrometry of combustion plumes

    NASA Astrophysics Data System (ADS)

    Bradley, Kenneth C.

    A midwave infrared (MWIR) imaging Fourier transform spectrometer (IFTS) was used to successfully capture and analyze hyperspectral imagery of combustion plumes. Jet engine exhaust data from a small turbojet engine burning diesel fuel at a low rate of 300 cm3/min was collected at 1 cm -1 resolution from a side-plume vantage point on a 200x64 pixel window at a range of 11.2 meters. Spectral features of H2O, CO, and CO2 were present, and showed spatial variability within the plume structure. An array of thermocouple probes was positioned within the plume to aid in temperature analysis. A single-temperature plume model was implemented to obtain spatially-varying temperatures and plume concentrations. Model-fitted temperatures of 811 +/- 1.5 K and 543 +/- 1.6 K were obtained from plume regions in close proximity to thermocouple probes measuring temperatures of 719 K and 522 K, respectively. Industrial smokestack plume data from a coal-burning stack collected at 0.25 cm-1 resolution at a range of 600 meters featured strong emission from NO, CO, CO2, SO 2, and HCl in the spectral region 1800-3000 cm-1. A simplified radiative transfer model was employed to derive temperature and concentrations for clustered regions of the 128x64 pixel scene, with corresponding statistical error bounds. The hottest region (closest to stack centerline) was 401 +/- 0.36 K, compared to an in-stack measurement of 406 K, and model-derived concentration values of NO, CO2, and SO2 were 140 +/- 1 ppmV, 110,400 +/- 950 ppmV, and 382 +/- 4 ppmV compared to in-stack measurements of 120 ppmV (NOx), 94,000 ppmV, and 382 ppmV, respectively. In-stack measurements of CO and HCl were not provided by the stack operator, but model-derived values of 19 +/- 0.2 ppmV and 111 +/- 1 ppmV are reported near stack centerline. A deployment to Dugway Proving Grounds, UT to collect hyperspectral imagery of chemical and biological threat agent simulants resulted in weak spectral signatures from several species. Plume

  5. Atmospheric chemistry in volcanic plumes.

    PubMed

    von Glasow, Roland

    2010-04-13

    Recent field observations have shown that the atmospheric plumes of quiescently degassing volcanoes are chemically very active, pointing to the role of chemical cycles involving halogen species and heterogeneous reactions on aerosol particles that have previously been unexplored for this type of volcanic plumes. Key features of these measurements can be reproduced by numerical models such as the one employed in this study. The model shows sustained high levels of reactive bromine in the plume, leading to extensive ozone destruction, that, depending on plume dispersal, can be maintained for several days. The very high concentrations of sulfur dioxide in the volcanic plume reduces the lifetime of the OH radical drastically, so that it is virtually absent in the volcanic plume. This would imply an increased lifetime of methane in volcanic plumes, unless reactive chlorine chemistry in the plume is strong enough to offset the lack of OH chemistry. A further effect of bromine chemistry in addition to ozone destruction shown by the model studies presented here, is the oxidation of mercury. This relates to mercury that has been coemitted with bromine from the volcano but also to background atmospheric mercury. The rapid oxidation of mercury implies a drastically reduced atmospheric lifetime of mercury so that the contribution of volcanic mercury to the atmospheric background might be less than previously thought. However, the implications, especially health and environmental effects due to deposition, might be substantial and warrant further studies, especially field measurements to test this hypothesis. PMID:20368458

  6. Atmospheric chemistry in volcanic plumes

    PubMed Central

    von Glasow, Roland

    2010-01-01

    Recent field observations have shown that the atmospheric plumes of quiescently degassing volcanoes are chemically very active, pointing to the role of chemical cycles involving halogen species and heterogeneous reactions on aerosol particles that have previously been unexplored for this type of volcanic plumes. Key features of these measurements can be reproduced by numerical models such as the one employed in this study. The model shows sustained high levels of reactive bromine in the plume, leading to extensive ozone destruction, that, depending on plume dispersal, can be maintained for several days. The very high concentrations of sulfur dioxide in the volcanic plume reduces the lifetime of the OH radical drastically, so that it is virtually absent in the volcanic plume. This would imply an increased lifetime of methane in volcanic plumes, unless reactive chlorine chemistry in the plume is strong enough to offset the lack of OH chemistry. A further effect of bromine chemistry in addition to ozone destruction shown by the model studies presented here, is the oxidation of mercury. This relates to mercury that has been coemitted with bromine from the volcano but also to background atmospheric mercury. The rapid oxidation of mercury implies a drastically reduced atmospheric lifetime of mercury so that the contribution of volcanic mercury to the atmospheric background might be less than previously thought. However, the implications, especially health and environmental effects due to deposition, might be substantial and warrant further studies, especially field measurements to test this hypothesis. PMID:20368458

  7. 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

    NASA Astrophysics Data System (ADS)

    Spicer, Chester W.; Holdren, Michael W.; Cowen, Kenneth A.; Joseph, Darrell W.; Satola, Jan; Goodwin, Bradley; Mayfield, Howard; Laskin, Alexander; Lizabeth Alexander, M.; Ortega, John V.; Newburn, Matthew; Kagann, Robert; Hashmonay, Ram

    Aircraft emissions affect air quality on scales from local to global. More than 20% of the jet fuel used in the U.S. is consumed by military aircraft, and emissions from this source are facing increasingly stringent environmental regulations, so improved methods for quickly and accurately determining emissions from existing and new engines are needed. This paper reports results of a study to advance the methods used for detailed characterization of military aircraft emissions, and provides emission factors for two aircraft: the F-15 fighter and the C-130 cargo plane. The measurements involved outdoor ground-level sampling downstream behind operational military aircraft. This permits rapid change-out of the aircraft so that engines can be tested quickly on operational aircraft. Measurements were made at throttle settings from idle to afterburner using a simple extractive probe in the dilute exhaust. Emission factors determined using this approach agree very well with those from the traditional method of extractive sampling at the exhaust exit. Emission factors are reported for CO 2, CO, NO, NO x, and more than 60 hazardous and/or reactive organic gases. Particle size, mass and composition also were measured and are being reported separately. Comparison of the emissions of nine hazardous air pollutants from these two engines with emissions from nine other aircraft engines is discussed.

  8. Three dimensional particle simulation of high altitude rocket plumes

    NASA Astrophysics Data System (ADS)

    Dagum, Leonardo; Zhu, S. H. K.

    1992-07-01

    The interaction of two nozzles exhausting into vacuum generates a complex three-dimensional shock structure. The shock structure and resulting plume flowfield is characterized by the nozzle separation distance. For the appropriate range of penetration Knudsen numbers, the analysis of this shock structure can be suitably accomplished through a Monte Carlo simulation. This paper describes the application of a general three-dimensional Monte Carlo simulation on the Connection Machine CM-2 to the analysis of the plume self-interaction shock in the near field. Results are presented for two cases, corresponding to a small and a large nozzle separation distance. The results correctly reproduce the expected flow features and demonstrate the ability of this method to properly simulate the start of the plume self-interaction shock. This has significance not only for allowing analysis of the self-interacting plume in the near field, but also for allowing the subsequent simulation of the far field flow through the use of a continuation downstream exit boundary.

  9. Measurement and analysis of a small nozzle plume in vacuum

    NASA Technical Reports Server (NTRS)

    Penko, P. F.; Boyd, I. D.; Meissner, D. L.; Dewitt, K. J.

    1993-01-01

    Pitot pressures and flow angles are measured in the plume of a nozzle flowing nitrogen and exhausting to a vacuum. Total pressures are measured with Pitot tubes sized for specific regions of the plume and flow angles measured with a conical probe. The measurement area for total pressure extends 480 mm (16 exit diameters) downstream of the nozzle exit plane and radially to 60 mm (1.9 exit diameters) off the plume axis. The measurement area for flow angle extends to 160 mm (5 exit diameters) downstream and radially to 60 mm. The measurements are compared to results from a numerical simulation of the flow that is based on kinetic theory and uses the direct-simulation Monte Carlo (DSMC) method. Comparisons of computed results from the DSMC method with measurements of flow angle display good agreement in the far-field of the plume and improve with increasing distance from the exit plane. Pitot pressures computed from the DSMC method are in reasonably good agreement with experimental results over the entire measurement area.

  10. Apollo Video Photogrammetry Estimation Of Plume Impingement Effects

    NASA Technical Reports Server (NTRS)

    Immer, Christopher; Lane, John; Metzger, Philip T.; Clements, Sandra

    2008-01-01

    The Constellation Project's planned return to the moon requires numerous landings at the same site. Since the top few centimeters are loosely packed regolith, plume impingement from the Lander ejects the granular material at high velocities. Much work is needed to understand the physics of plume impingement during landing in order to protect hardware surrounding the landing sites. While mostly qualitative in nature, the Apollo Lunar Module landing videos can provide a wealth of quantitative information using modem photogrammetry techniques. The authors have used the digitized videos to quantify plume impingement effects of the landing exhaust on the lunar surface. The dust ejection angle from the plume is estimated at 1-3 degrees. The lofted particle density is estimated at 10(exp 8)- 10(exp 13) particles per cubic meter. Additionally, evidence for ejection of large 10-15 cm sized objects and a dependence of ejection angle on thrust are presented. Further work is ongoing to continue quantitative analysis of the landing videos.

  11. Formation, Dynamics, and Impact of Plasmaspheric Plumes

    NASA Astrophysics Data System (ADS)

    Goldstein, Jerry; Borovsky, Joseph; Foster, John; Carpenter, Donald

    2007-06-01

    Workshop on Plasmaspheric Drainage Plumes, Taos, New Mexico, 9-13 October 2006 Plasmaspheric plumes result from erosion of the plasmasphere. The Institute of Geophysics and Planetary Physics (IGPP) Workshop on Plasmaspheric Drainage Plumes was convened in Taos, N. M., on 9-13 October 2006 to examine outstanding questions about the formation and dynamics of plumes, and the impact of plumes on the near-Earth space environment (geospace). A second workshop on plasmaspheric drainage plumes is planned for late 2007.

  12. An expert system for spectroscopic analysis of rocket engine plumes

    NASA Technical Reports Server (NTRS)

    Reese, Greg; Valenti, Elizabeth; Alphonso, Keith; Holladay, Wendy

    1991-01-01

    The expert system described in this paper analyzes spectral emissions of rocket engine exhaust plumes and shows major promise for use in engine health diagnostics. Plume emission spectroscopy is an important tool for diagnosing engine anomalies, but it is time-consuming and requires highly skilled personnel. The expert system was created to alleviate such problems. The system accepts a spectral plot in the form of wavelength vs intensity pairs and finds the emission peaks in the spectrum, lists the elemental emitters present in the data and deduces the emitter that produced each peak. The system consists of a conventional language component and a commercially available inference engine that runs on an Apple Macintosh computer. The expert system has undergone limited preliminary testing. It detects elements well and significantly decreases analysis time.

  13. Observation and Modeling of the Evolution of Texas Power Plant Plumes

    EPA Science Inventory

    During the second Texas Air Quality Study 2006 (TexAQS II), a full range of pollutants was measured by aircraft in eastern Texas during successive transects of power plant plumes (PPPs). A regional photochemical model is applied to simulate the physical and chemical evolution of ...

  14. D-558-2 being mounted to P2B-1S launch aircraft

    NASA Technical Reports Server (NTRS)

    1953-01-01

    aircraft of that era, particularly at low speeds during take-off and landing and in tight turns. The three aircraft gathered a great deal of data about pitch-up and the coupling of lateral (yaw) and longitudinal (pitch) motions; wing and tail loads, lift, drag, and buffeting characteristics of swept-wing aircraft at transonic and supersonic speeds; and the effects of the rocket exhaust plume on lateral dynamic stability throughout the speed range. (Plume effects were a new experience for aircraft.) The number three aircraft also gathered information about the effects of external stores (bomb shapes, drop tanks) upon the aircraft's behavior in the transonic region (roughly 0.7 to 1.3 times the speed of sound). In correlation with data from other early transonic research aircraft such as the XF-92A, this information contributed to solutions to the pitch-up problem in swept-wing aircraft. The three airplanes flew a total of 313 times--123 by the number one aircraft (Bureau No. 37973--NACA 143), 103 by the second Skyrocket (Bureau No. 37974--NACA 144), and 87 by airplane number three (Bureau No. 37975--NACA 145). Skyrocket 143 flew all but one of its missions as part of the Douglas contractor program to test the airplane's performance. NACA aircraft 143 was initially powered by a Westinghouse J-34-40 turbojet engine configured only for ground take-offs, but in 1954-55 the contractor modified it to an all-rocket air-launch capability featuring an LR8-RM-6, 4-chamber Reaction Motors engine rated at 6,000 pounds of thrust at sea level (the Navy designation for the Air Force's LR-11 used in the X-1). In this configuration, NACA research pilot John McKay flew the airplane only once for familiarization on September 17, 1956. The 123 flights of NACA 143 served to validate wind-tunnel predictions of the airplane's performance, except for the fact that the airplane experienced less drag above Mach 0.85 than the wind tunnels had indicated. NACA 144 also began its flight program with a

  15. D-558-2 being mounted to P2B-1S launch aircraft

    NASA Technical Reports Server (NTRS)

    1953-01-01

    aircraft gathered a great deal of data about pitch-up and the coupling of lateral (yaw) and longitudinal (pitch) motions; wing and tail loads, lift, drag, and buffeting characteristics of swept-wing aircraft at transonic and supersonic speeds; and the effects of the rocket exhaust plume on lateral dynamic stability throughout the speed range. (Plume effects were a new experience for aircraft.) The number three aircraft also gathered information about the effects of external stores (bomb shapes, drop tanks) upon the aircraft's behavior in the transonic region (roughly 0.7 to 1.3 times the speed of sound). In correlation with data from other early transonic research aircraft such as the XF-92A, this information contributed to solutions to the pitch-up problem in swept-wing aircraft. The three airplanes flew a total of 313 times--123 by the number one aircraft (Bureau No. 37973--NACA 143), 103 by the second Skyrocket (Bureau No. 37974--NACA 144), and 87 by airplane number three (Bureau No. 37975--NACA 145). Skyrocket 143 flew all but one of its missions as part of the Douglas contractor program to test the airplane's performance. NACA aircraft 143 was initially powered by a Westinghouse J-34-40 turbojet engine configured only for ground take-offs, but in 1954-55 the contractor modified it to an all-rocket air-launch capability featuring an LR8-RM-6, 4-chamber Reaction Motors engine rated at 6,000 pounds of thrust at sea level (the Navy designation for the Air Force's LR-11 used in the X-1). In this configuration, NACA research pilot John McKay flew the airplane only once for familiarization on September 17, 1956. The 123 flights of NACA 143 served to validate wind-tunnel predictions of the airplane's performance, except for the fact that the airplane experienced less drag above Mach 0.85 than the wind tunnels had indicated. NACA 144 also began its flight program with a turbojet powerplant. NACA pilots Robert A. Champine and John H. Griffith flew 21 times in this configuration

  16. Emission characteristics of black carbon in anthropogenic and biomass burning plumes over California during ARCTAS-CARB 2008

    NASA Astrophysics Data System (ADS)

    Sahu, L. K.; Kondo, Y.; Moteki, N.; Takegawa, N.; Zhao, Y.; Cubison, M. J.; Jimenez, J. L.; Vay, S.; Diskin, G. S.; Wisthaler, A.; Mikoviny, T.; Huey, L. G.; Weinheimer, A. J.; Knapp, D. J.

    2012-08-01

    The impact of aerosols on regional air quality and climate necessitates improved understanding of their emission and microphysical properties. The size distributions of black carbon (BC) and light scattering particles (LSP) were measured with a single particle soot photometer on board the NASA DC-8 aircraft during the ARCTAS mission 2008. Air sampling was made in the air plumes of both urban and forest fire emissions over California during the CARB (California Air Resources Board) phase of the mission. A total of eleven plumes were identified using SO2 and CH3CN tracers for fossil fuel (FF) combustion and biomass burning (BB), respectively. The enhancements of BC and LSP in BB plumes were significantly higher compared to those in FF plumes. The average mass concentration of BC in BB plumes was more than twice that in FF plumes. Except for the BC/CO ratio, distinct emission ratios of BC/CO2, BC/CH3CN, CH3CN/CO, and CO/CO2 were observed in the plumes from the two sources. Similarly, the microphysical properties of BC and LSP also showed distinct behaviors. The BC count median diameter (CMD) of 115 ± 5 nm in FF plumes was smaller compared to 141 ± 9 nm in the BB plumes. BC aerosols were thickly coated in BB plumes, the average shell/core ratios were 1.47 and 1.24 in BB and FF plumes, respectively. In the total mass of submicron aerosols, organic aerosols constituted about 67% in the FF plumes and 84% in BB plumes. The contribution of sulfate was also significant in the FF plumes.

  17. Scanning thermal plumes

    NASA Technical Reports Server (NTRS)

    Scarpace, F. L.; Madding, R. P.; Green, T., III

    1975-01-01

    Over a three-year period 800 thermal line scans of power plant plumes were made by an airborne scanner, with ground truth measured concurrently at the plants. Computations using centered finite differences in the thermal scanning imagery show a lower bound in the horizontal temperature gradient in excess of 1.6 C/m. Gradients persist to 3 m below the surface. Vector plots of the velocity of thermal fronts are constructed by tracing the front motion in successive thermal images. A procedure is outlined for the two-point ground calibration of a thermal scanner from an equation describing the scanner signal and the voltage for two known temperatures. The modulation transfer function is then calculated by input of a thermal step function and application of digital time analysis techniques using Fast Fourier Transforms to the voltage output. Field calibration tests are discussed. Data accuracy is limited by the level of ground truth effort chosen.

  18. DIRECT MEASUREMENT OF MERCURY REACTIONS IN COAL POWER PLANT PLUMES

    SciTech Connect

    Leonard Levin

    2004-01-01

    -September 5, 2003. The experimental site was the Pleasant Prairie Power Plant in Pleasant Prairie, Wisconsin, just west of Kenosha. The experiment involved using an aircraft to capture emissions and document chemistry changes in the plume. While using the airplane for sampling, supplemental fast-response sensors for NOx, connected to data loggers, were used to gauge entry and exit times and transect intervals through plume emissions material. The Frontier Geosciences Static Plume Dilution Chamber (SPDC) was employed simultaneously adjacent to the stack to correlate its findings with the aircraft sampling, as well as providing evaluation of the SPDC as a rapid, less costly sampler for mercury chemistry. A complementary stack plume method, the Dynamic Plume Dilution (DPD) was used in the latter portion of the experiment to measure mercury speciation to observe any mercury reduction reaction with respect to both the reaction time (5 to 30 seconds) and dilution ratio. In addition, stack sampling using the ''Ontario Hydro'' wet chemistry method and continuous mercury monitors (CMM) were used to establish the baseline chemistry in the stack. Comparisons among stack, SPDC, DPD and aircraft measurements following data analysis will allow establishment of whether significant chemical changes to mercury occur in the plume, and of the verisimilitude of the SPDC and DPD methods.

  19. AIRCRAFT OBSERVATIONS OF EXTREME OZONE CONCENTRATIONS NEAR THUNDERSTORMS

    EPA Science Inventory

    Anomalously large short-term ozone concentrations were observed on several occasions by aircraft during an experiment on August 5, 1980, to characterize the physical and chemical properties of the Baltimore urban plume. The ozone 'spikes' of about 500 ppb were traversed by aircra...

  20. HSCT noise reduction technology development at GE Aircraft Engines

    NASA Astrophysics Data System (ADS)

    Majjigi, Rudramuni K.

    1992-04-01

    The topics covered include the following: High Speed Civil Transport (HSCT) exhaust nozzle design approaches; GE aircraft engine (GEAE) HSCT acoustics research; 2DCD non-IVP suppressor ejector; key sensitivities from reference aircraft; acoustic experiments; aero-mixing experimental set-up; fluid shield nozzle; HSCT Mach 2.4 flade nozzle; noise prediction; nozzle concept for GE/Boeing joint test; scale model hot core flow path modified to prevent hub-choking CFL3-D solution; HSCT exhaust nozzle status; and key acoustic technology issues for HSCT's.

  1. The numerical calculation of inviscid plume flow fields

    NASA Technical Reports Server (NTRS)

    Salas, M. D.

    1974-01-01

    A numerical method is presented for the computation of inviscid, axisymmetric, underexpanded plumes. The numerical techniques developed by Moretti (1969, 1971, 1972) are used in conjunction with Abbett's (1970) theory for locating the Mach disk. Abbett's theory and three other prediction methods are compared to experimental results. Results are presented for jets exhausting into static ambients and supersonic free stream. Detailed results from a flow field with multiple Mach disks are also presented. Finally, some problems associated with the computation of very small Mach disks are discussed.

  2. Particulate sizing and emission indices for a jet engine exhaust sampled at cruise

    NASA Astrophysics Data System (ADS)

    Hagen, D.; Whitefield, P.; Paladino, J.; Trueblood, M.; Lilenfeld, H.

    Particle size and emission indices measurements for jet engines, primarily the Rolls Royce RB211 engines on a NASA 757 aircraft are reported. These data were used to estimate the fraction of fuel sulfur that was converted to particulates. These measurements were made in-situ with the sampling aircraft several kilometers behind the source. Some complimentary ground measurements on the same source aircraft and engines are also reported. Significant differences are seen between the ground observations and the in-situ observations, indicating that plume processes are changing the aerosol's characteristics.

  3. El chichon: composition of plume gases and particles.

    PubMed

    Kotra, J P; Finnegan, D L; Zoller, W H; Hart, M A; Moyers, J L

    1983-12-01

    Aircraft measurements were made of trace gases, atmospheric particles, and condensed acid volatiles in the plume of El Chichón volcano, Chiapas, Mexico, in November 1982. Hydrogen sulfide was the primary gaseous sulfur species in the plume at the time of collection. Concentrations of 28 elements were determined by neutron activation analysis of particulate material from the plume. Rates of trace element emission to the atmosphere for each species were estimated by normlization to the simultaneously determined total sulfur emission rate. The volatile elements sulfur, chlorine, arsenic, selenium, bromine, antimony, iodine, tungsten, and mercury were enriched relative to bulk pyroclastic material by factors of 60 to 20,000. Arsenic, antimony, and selenium were associated predominantly with small (>/= 3 micrometer) particles. Calcium and sodium were present almost exclusively on larger particles and aluminum and manganese were bimodally distributed. Ashladen particulate material injected into the stratosphere during the early violent eruptions was enriched by factors of 10 to 30 relative to ash in some of the same elements observed in the quiescent plume. PMID:17776246

  4. 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

  5. The ARCTAS aircraft mission: design and execution

    NASA Astrophysics Data System (ADS)

    Jacob, D. J.; Crawford, J. H.; Maring, H. B.; Clarke, A. D.; Dibb, J. E.; Ferrare, R. A.; Hostetler, C. A.; Russell, P. B.; Singh, H. B.; Thompson, A. M.; Shaw, G. E.; McCauley, E.; Pederson, J. R.; Fisher, J. A.

    2009-12-01

    We present an overview of the NASA Arctic Research of the Composition of the Troposphere from Aircraft and Satellites (ARCTAS) mission, conducted in two 3-week deployments based in Alaska (April 2008) and western Canada (June-July 2008). The goal of ARCTAS was to better understand the factors driving current changes in Arctic atmospheric composition and climate, including (1) transport of mid-latitude pollution, (2) boreal forest fires, (3) aerosol radiative forcing, and (4) chemical processes. ARCTAS involved three aircraft: a DC-8 with detailed chemical payload, a P-3 with extensive aerosol payload, and a B-200 with aerosol remote sensing instrumentation. The aircraft augmented satellite observations of Arctic atmospheric composition, in particular from the NASA A-Train, by (1) validating the data, (2) improving constraints on retrievals, (3) making correlated observations, and (4) characterizing chemical and aerosol processes. The April flights (ARCTAS-A) sampled pollution plumes from all three mid-latitude continents, fire plumes from Siberia and Southeast Asia, and halogen radical events. The June-July flights (ARCTAS-B) focused on boreal forest fire influences and sampled fresh fire plumes from northern Saskatchewan as well as older fire plumes from Canada, Siberia, and California. The June-July deployment was preceded by one week of flights over California sponsored by the California Air Resources Board (ARCTAS-CARB). The ARCTAS-CARB goals were to (1) improve state emission inventories for greenhouse gases and aerosols, (2) provide observations to test and improve models of ozone and aerosol pollution. Extensive sampling across southern California and the Central Valley characterized emissions from urban centers, offshore shipping lanes, agricultural crops, feedlots, industrial sources, and wildfires.

  6. Hot streak characterization in serpentine exhaust nozzles

    NASA Astrophysics Data System (ADS)

    Crowe, Darrell S.

    Modern aircraft of the United States Air Force face increasingly demanding cost, weight, and survivability requirements. Serpentine exhaust nozzles within an embedded engine allow a weapon system to fulfill mission survivability requirements by providing denial of direct line-of-sight into the high-temperature components of the engine. Recently, aircraft have experienced material degradation and failure along the aft deck due to extreme thermal loading. Failure has occurred in specific regions along the aft deck where concentrations of hot gas have come in contact with the surface causing hot streaks. The prevention of these failures will be aided by the accurate prediction of hot streaks. Additionally, hot streak prediction will improve future designs by identifying areas of the nozzle and aft deck surfaces that require thermal management. To this end, the goal of this research is to observe and characterize the underlying flow physics of hot streak phenomena. The goal is accomplished by applying computational fluid dynamics to determine how hot streak phenomena is affected by changes in nozzle geometry. The present research first validates the computational methods using serpentine inlet experimental and computational studies. A design methodology is then established for creating six serpentine exhaust nozzles investigated in this research. A grid independent solution is obtained on a nozzle using several figures of merit and the grid-convergence index method. An investigation into the application of a second-order closure turbulence model is accomplished. Simulations are performed for all serpentine nozzles at two flow conditions. The research introduces a set of characterization and performance parameters based on the temperature distribution and flow conditions at the nozzle throat and exit. Examination of the temperature distribution on the upper and lower nozzle surfaces reveals critical information concerning changes in hot streak phenomena due to changes

  7. Remote monitoring of the Gravelly Run thermal plume at Hopewell and the thermal plume at the Surry Nuclear Power Plant on the James River

    NASA Technical Reports Server (NTRS)

    Talay, T. A.; Sykes, K. W.; Kuo, C. Y.

    1979-01-01

    On May 17, 1977, a remote sensing experiment was conducted on the James River, Virginia, whereby thermal spectrometer and near-infrared photography data of thermal discharges at Hopewell and the Surry nuclear power plant were obtained by an aircraft for one tidal cycle. These data were used in subsequent investigations into the near field discharge trajectories. For the Gravelly Run thermal plume at Hopewell, several empirical expressions for the plume centerline were evaluated by comparisons of the computed trajectories and those observed in the remote sensing images.

  8. A new method for GPS-based wind speed determinations during airborne volcanic plume measurements

    USGS Publications Warehouse

    Doukas, Michael P.

    2002-01-01

    Begun nearly thirty years ago, the measurement of gases in volcanic plumes is today an accepted technique in volcano research. Volcanic plume measurements, whether baseline gas emissions from quiescent volcanoes or more substantial emissions from volcanoes undergoing unrest, provide important information on the amount of gaseous output of a volcano to the atmosphere. Measuring changes in gas emission rates also allows insight into eruptive behavior. Some of the earliest volcanic plume measurements of sulfur dioxide were made using a correlation spectrometer (COSPEC). The COSPEC, developed originally for industrial pollution studies, is an upward-looking optical spectrometer tuned to the ultraviolet absorption wavelength of sulfur dioxide (Millán and Hoff, 1978). In airborne mode, the COSPEC is mounted in a fixed-wing aircraft and flown back and forth just underneath a volcanic plume, perpendicular to the direction of plume travel (Casadevall and others, 1981; Stoiber and others, 1983). Similarly, for plumes close to the ground, the COSPEC can be mounted in an automobile and driven underneath a plume if a suitable road system is available (Elias and others, 1998). The COSPEC can also be mounted on a tripod and used to scan a volcanic plume from a fixed location on the ground, although the effectiveness of this configuration declines with distance from the plume (Kyle and others, 1990). In the 1990’s, newer airborne techniques involving direct sampling of volcanic plumes with infrared spectrometers and electrochemical sensors were developed in order to measure additional gases such as CO2 and H2S (Gerlach and others, 1997; Gerlach and others, 1999; McGee and others, 2001). These methods involve constructing a plume cross-section from several measurement traverses through the plume in a vertical plane. Newer instruments such as open-path Fourier transform infrared (FTIR) spectrometers are now being used to measure the gases in volcanic plumes mostly from fixed

  9. Exhaust gas ignition

    SciTech Connect

    1996-04-01

    This article describes a system developed for rapid light-off of underbody catalysts that has shown potential to meet Euro Stage III emissions targets and to be more cost-effective than some alternatives. Future emissions legislation will require SI engine aftertreatment systems to approach full operating efficiency within the first few seconds after starting to reduce the high total-emissions fraction currently contributed by the cold phase of driving. A reduction of cold-start emissions during Phase 1 (Euro) or Bag 1 (FTP), which in many cases can be as much as 80% of the total for the cycle, has been achieved by electrical heating of the catalytic converter. But electrically heated catalyst (EHC) systems require high currents (100--200 A) to heat the metallic substrate to light-off temperatures over the first 15--20 seconds. Other viable approaches to reducing cold-start emissions include use of a fuel-powered burner upstream of the catalyst. However, as with EHC, the complexity of parts and the introduction of raw fuel into the exhaust system make this device unsatisfactory. Still another approach, an exhaust gas ignition (EGI) system, was first demonstrated in 1991. The operation of a system developed by engineers at Ford Motor Co., Ltd., Cambustion Ltd., and Tickford Ltd. is described here.

  10. Educating with Aircraft Models

    ERIC Educational Resources Information Center

    Steele, Hobie

    1976-01-01

    Described is utilization of aircraft models, model aircraft clubs, and model aircraft magazines to promote student interest in aerospace education. The addresses for clubs and magazines are included. (SL)

  11. COMPARING AND LINKING PLUMES ACROSS MODELING APPROACHES

    EPA Science Inventory

    River plumes carry many pollutants, including microorganisms, into lakes and the coastal ocean. The physical scales of many stream and river plumes often lie between the scales for mixing zone plume models, such as the EPA Visual Plumes model, and larger-sized grid scales for re...

  12. Ozone production in the New York City urban plume

    NASA Astrophysics Data System (ADS)

    Kleinman, Lawrence I.; Daum, Peter H.; Imre, Dan G.; Lee, Jai H.; Lee, Yin-Nan; Nunnermacker, Linda J.; Springston, Stephen R.; Weinstein-Lloyd, Judith; Newman, Leonard

    2000-06-01

    In the summer of 1996 the Department of Energy G-1 aircraft was deployed in the New York City metropolitan area as part of the North American Research Strategy for Tropospheric Ozone-Northeast effort to determine the causes of elevated O3 levels in the northeastern United States. Measurements of O3, O3 precursors, and other photochemically active trace gases were made upwind and downwind of New York City with the objective of characterizing the O3 formation process and its dependence on ambient levels of NOx and volatile organic compounds (VOCs). Four flights are discussed in detail. On two of these flights, winds were from the W-SW, which is the typical direction for an O3 episode. On the other two flights, winds were from the NW, which puts a cleaner area upwind of the city. The data presented include plume and background values of O3, CO, NOx, and NOy concentration and VOC reactivity. On the W-SW flow days O3 reached 110 ppb. According to surface observations the G-1 intercepted the plume close to the region where maximum O3 occurred. At this point the ratio NOx/NOy was 20-30%, indicating an aged plume. Plume values of CO/NOy agree to within 20% with emission estimates from the core of the New York City metropolitan area. Steady state photochemical calculations were performed using observed or estimated trace gas concentrations as constraints. According to these calculations the local rate of O3 production P(O3) in all four plumes is VOC sensitive, sometimes strongly so. The local sensitivity calculations show that a specified fractional decrease in VOC concentration yields a similar magnitude fractional decrease in P(O3). Imposing a decrease in NOx, however, causes P(O3) to increase. The question of primary interest from a regulatory point of view is the sensitivity of O3 concentration to changes in emissions of NOx and VOCs. A qualitative argument is given that suggests that the total O3 formed in the plume, which depends on the entire time evolution of the

  13. Volatile nanoparticle formation and growth within a diluting diesel car exhaust.

    PubMed

    Uhrner, Ulrich; Zallinger, Michael; von Löwis, Sibylle; Vehkamäki, Hanna; Wehner, Birgit; Stratmann, Frank; Wiedensohler, Alfred

    2011-04-01

    A major source of particle number emissions is road traffic. However, scientific knowledge concerning secondary particle formation and growth of ultrafine particles within vehicle exhaust plumes is still very limited. Volatile nanoparticle formation and subsequent growth conditions were analyzed here to gain a better understanding of "real-world" dilution conditions. Coupled computational fluid dynamics and aerosol microphysics models together with measured size distributions within the exhaust plume of a diesel car were used. The impact of soot particles on nucleation, acting as a condensational sink, and the possible role of low-volatile organic components in growth were assessed. A prescribed reduction of soot particle emissions by 2 orders of magnitude (to capture the effect of a diesel particle filter) resulted in concentrations of nucleation-mode particles within the exhaust plume that were approximately 1 order of magnitude larger. Simulations for simplified sulfuric acid-water vapor gas-oil containing nucleation-mode particles show that the largest particle growth is located in a recirculation zone in the wake of the car. Growth of particles within the vehicle exhaust plume up to detectable size depends crucially on the relationship between the mass rate of gaseous precursor emissions and rapid dilution. Chassis dynamometer measurements indicate that emissions of possible hydrocarbon precursors are significantly enhanced under high engine load conditions and high engine speed. On the basis of results obtained for a diesel passenger car, the contributions from light diesel vehicles to the observed abundance of measured nucleation-mode particles near busy roads might be attributable to the impact of two different time scales: (1) a short one within the plume, marked by sufficient precursor emissions and rapid dilution; and (2) a second and comparatively long time scale resulting from the mix of different precursor sources and the impact of atmospheric

  14. Space shuttle vehicle rocket plume impingement study for separation analysis. Tasks 2 and 3: Definition and preliminary plume impingement analysis for the MSC booster

    NASA Technical Reports Server (NTRS)

    Wojciechowski, C. J.; Penny, M. M.; Prozan, R. J.

    1970-01-01

    The results are presented of a space shuttle plume impingement study for the Manned Spacecraft Center configuration. This study was conducted as two tasks which were to (1) define the orbiter main stage engine exhaust plume flow field, and (2) define the plume impingement heating, force and resulting moment environments on the booster during the staging maneuver. To adequately define these environments during the staging maneuver and allow for deviation from the nominal separation trajectory, a multitude of relative orbiter/booster positions are analyzed which map the region that contains the separation trajectories. The data presented can be used to determine a separation trajectory which will result in acceptable impingement heating rates, forces, and the resulting moments. The data, presented in graphical form, include the effect of roll, pitch and yaw maneuvers for the booster. Quasi-steady state analysis methods were used with the orbiter engine operating at full thrust. To obtain partial thrust results, simple ratio equations are presented.

  15. Precursor gases of aerosols in the Mount St. Helens eruption plumes at stratospheric altitudes

    NASA Technical Reports Server (NTRS)

    Inn, E. C. Y.; Vedder, J. F.; Condon, E. P.; Ohara, D.

    1982-01-01

    Nineteen stratospheric samples from the eruption plumes of Mount St. Helens were collected in five flight experiments. The plume samples were collected at various altitudes from 13.1 to 20.7 km by using the Ames cryogenic sampling system on board the NASA U-2 aircraft. The enriched, cryogenically collected samples were analyzed by chromatography. The concentrations of aerosols precursor gases (OCS, SO2, and CS2), CH3Cl, N2O, CF2Cl2, and CFCl3 were measured by gas chromatography. Large enhancement of the mixing ratio of SO2 and moderate enhancement of CS2 and OCS were found in the plume samples compared with similar measurement under pre-volcanic conditions. A fast decay rate of the SO2 mixing ratio in the plume was observed. Measurement of Cl(-), SO2(2-), and NO3(-) by ion chromatography was also carried out on water solutions prepared from the plume samples. The results obtained with this technique imply large mixing ratios of HCl, (NO + NO2 + HNO3), and SO2, in which these constituents are the respective sources of the anions. Measurement of the Rn222 concentration in the plume was made. Other stratospheric constituents in the plume samples, such as H2O, CO2, CH4, and CO, were also observed.

  16. Variable area exhaust nozzle

    NASA Technical Reports Server (NTRS)

    Johnston, E. A. (Inventor)

    1979-01-01

    An exhaust nozzle for a gas turbine engine comprises a number of arcuate flaps pivotally connected to the trailing edge of a cylindrical casing which houses the engine. Seals disposed within the flaps are spring biased and extensible beyond the side edges of the flaps. The seals of adjacent flaps are maintained in sealing engagement with each other when the flaps are adjusted between positions defining minimum nozzle flow area and the cruise position. Extensible, spring biased seals are also disposed within the flaps adjacent to a supporting pylon to thereby engage the pylon in a sealing arrangement. The flaps are hinged to the casing at the central portion of the flaps' leading edges and are connected to actuators at opposed outer portions of the leading edges to thereby maximize the mechanical advantage in the actuation of the flaps.

  17. Interactive aircraft flight control and aeroelastic stabilization

    NASA Technical Reports Server (NTRS)

    Weisshaar, T. A.; Schmidt, D. K.

    1984-01-01

    The potential benefits and costs of optimizing both the structural stiffness and the active control of aircraft in a rational manner are investigated. The ultimate goal is to arrive at a unified treatment of structural and active control design for the stability augmentation of flexible aircraft. An exhaustive literature evaluation in the area of passive tailoring for aircraft performance is undertaken. A mathematical technique to be used for aeroservoelastic tailoring studies is described. Two analytical models, one elementary, the other sophisticated, are developed to illustrate the potential for aeroservoelastic tailoring. Both models have essential features of real world hardware, yet the physical understanding is not buried in a myriad of detail. These models are also described.

  18. 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

    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%). However, the blended fuels had less of a reduction (reductions of 30-44%) than initially measured (64%). The likely explanation is that the reduced soot emissions in the blended fuel exhaust plume results in promotion of new particle formation microphysics, rather than coating on pre-existing soot particles, which is dominant in the JP-8 exhaust plume. Downwind particle volume emissions were reduced for both the pure (79 and 86% reductions) and blended FT fuels (36 and 46%) due to the large reductions in soot emissions. In addition, the alternative fuels had reduced particulate sulfate production (near zero for FT fuels) due to decreased fuel sulfur content. To study the formation of volatile aerosols (defined as any aerosol formed as the plume ages) in more detail, tests were performed at varying ambient temperatures (-4 to 20 °C). At idle, particle number and volume emissions were reduced linearly with increasing ambient temperature, with best fit slopes corresponding to -8 × 1014 particles (kg fuel)-1 °C-1 for particle number emissions and -10 mm3 (kg fuel)-1 °C-1 for particle volume emissions. The temperature dependency of aerosol formation can have large effects on local air quality surrounding airports in cold regions. Aircraft-produced aerosols in these regions will be much larger than levels expected based solely on measurements made directly at the engine exit plane. The majority (90% at idle) of the volatile aerosol mass formed as nucleation-mode aerosols, with a smaller fraction as a soot coating. Conversion efficiencies of up to 2.8% were measured for the partitioning of gas-phase precursors (unburned hydrocarbons and SO2) to form volatile aerosols. Highest conversion efficiencies were measured at 45% power.

  19. Comprehensive simultaneous shipboard and airborne characterization of exhaust from a modern container ship at sea.

    PubMed

    Murphy, Shane M; Agrawal, Harshit; Sorooshian, Armin; Padró, Luz T; Gates, Harmony; Hersey, Scott; Welch, W A; Lung, H; Miller, J W; Cocker, David R; Nenes, Athanasios; Jonsson, Haflidi H; Flagan, Richard C; Seinfeld, John H

    2009-07-01

    We report the first joint shipboard and airborne study focused on the chemical composition and water-uptake behavior of particulate ship emissions. The study focuses on emissions from the main propulsion engine of a Post-Panamax class container ship cruising off the central coast of California and burning heavy fuel oil. Shipboard sampling included micro-orifice uniform deposit impactors (MOUDI) with subsequent off-line analysis, whereas airborne measurements involved a number of real-time analyzers to characterize the plume aerosol, aged from a few seconds to over an hour. The mass ratio of particulate organic carbon to sulfate at the base of the ship stack was 0.23 +/- 0.03, and increased to 0.30 +/- 0.01 in the airborne exhaust plume, with the additional organic mass in the airborne plume being concentrated largely in particles below 100 nm in diameter. The organic to sulfate mass ratio in the exhaust aerosol remained constant during the first hour of plume dilution into the marine boundary layer. The mass spectrum of the organic fraction of the exhaust aerosol strongly resembles that of emissions from other diesel sources and appears to be predominantly hydrocarbon-like organic (HOA) material. Background aerosol which, based on air mass back trajectories, probably consisted of aged ship emissions and marine aerosol, contained a lower organic mass fraction than the fresh plume and had a much more oxidized organic component. A volume-weighted mixing rule is able to accurately predict hygroscopic growth factors in the background aerosol but measured and calculated growth factors do not agree for aerosols in the ship exhaust plume. Calculated CCN concentrations, at supersaturations ranging from 0.1 to 0.33%, agree well with measurements in the ship-exhaust plume. Using size-resolved chemical composition instead of bulk submicrometer composition has little effect on the predicted CCN concentrations because the cutoff diameter for CCN activation is larger than the

  20. Active Volcanic Plumes on Io

    NASA Technical Reports Server (NTRS)

    1997-01-01

    This color image, acquired during Galileo's ninth orbit around Jupiter, shows two volcanic plumes on Io. One plume was captured on the bright limb or edge of the moon (see inset at upper right), erupting over a caldera (volcanic depression) named Pillan Patera after a South American god of thunder, fire and volcanoes. The plume seen by Galileo is 140 kilometers (86 miles) high and was also detected by the Hubble Space Telescope. The Galileo spacecraft will pass almost directly over Pillan Patera in 1999 at a range of only 600 kilometers (373 miles).

    The second plume, seen near the terminator (boundary between day and night), is called Prometheus after the Greek fire god (see inset at lower right). The shadow of the 75-kilometer (45- mile) high airborne plume can be seen extending to the right of the eruption vent. The vent is near the center of the bright and dark rings. Plumes on Io have a blue color, so the plume shadow is reddish. The Prometheus plume can be seen in every Galileo image with the appropriate geometry, as well as every such Voyager image acquired in 1979. It is possible that this plume has been continuously active for more than 18 years. In contrast, a plume has never been seen at Pillan Patera prior to the recent Galileo and Hubble Space Telescope images.

    North is toward the top of the picture. The resolution is about 6 kilometers (3.7 miles) per picture element. This composite uses images taken with the green, violet and near infrared filters of the solid state imaging (CCD) system on NASA's Galileo spacecraft. The images were obtained on June 28, 1997, at a range of more than 600,000 kilometers (372,000 miles).

    The Jet Propulsion Laboratory, Pasadena, CA manages the Galileo mission for NASA's Office of Space Science, Washington, DC. JPL is an operating division of California Institute of Technology (Caltech).

    This image and other images and data received from Galileo are posted on the World Wide Web, on the Galileo mission home page

  1. Particle Rotation Effects in Rarefied Two-Phase Plume Flows

    NASA Astrophysics Data System (ADS)

    Burt, Jonathan M.; Boyd, Iain D.

    2005-05-01

    We evaluate the effects of solid particle rotation in high-altitude solid rocket exhaust plume flows, through the development and application of methods for the simulation of two phase flows involving small rotating particles and a nonequilibrium gas. Green's functions are derived for the force, moment, and heat transfer rate to a rotating solid sphere within a locally free-molecular gas, and integration over a Maxwellian gas velocity distribution is used to determine the influence of particle rotation on the heat transfer rate at the equilibrium limit. The use of these Green's functions for the determination of particle phase properties through the Direct Simulation Monte Carlo method is discussed, and a procedure is outlined for the stochastic modeling of interphase collisions. As a test case, we consider the nearfield plume flow for a Star-27 solid rocket motor exhausting into a vacuum, and vary particle angular velocities at the nozzle exit plane in order to evaluate the influence of particle rotation on various flow properties. Simulation results show that rotation may lead to slightly higher particle temperatures near the central axis, but for the case considered the effects of particle rotation are generally found to be negligible.

  2. Community sensitivity to changes in aircraft noise exposure

    NASA Technical Reports Server (NTRS)

    Fidell, S.; Horonjeff, R.; Teffeteller, S.; Pearsons, K.

    1981-01-01

    Interviews were conducted in the vicinity of Burbank Airport during a four month period during which a counterbalanced series of changes in aircraft noise exposure occurred due to runway repairs. Another interview was undertaken approximately one year after completion of the initial runway repairs. Noise measurements were made in conjunction with administration of a brief questionnaire to a near exhaustive sample of residents in four airport neighborhoods. The magnitude and direction of change of annoyance with aircraft noise exposure corresponded closely to the actual changes in physical exposure. Estimates were made of time constants for the rate of change of attitudes toward aircraft noise.

  3. Trace gas measurements in the Kuwait oil fire smoke plume

    SciTech Connect

    Luke, W.T.; Kok, G.L.; Schillawski, R.D.; Zimmerman, P.R.; Greenberg, J.P.; Kadavanich, M.

    1992-09-20

    The authors report trace gas measurements made both inside and outside the Kuwait oil-fire smoke plume during a flight of an instrumented research aircraft on May 30, 1991. Concentrations of SO{sub 2}, CO, and NO{sub x} averaged vertically and horizontally throughout the plume 80 km downwind of Kuwait City were 106, 127, and 9.1 parts per billion by volume (ppbv), respectively, above background concentrations. With the exception of SO{sub 2}, trace gas concentrations were far below typical US urban levels and primary national ambient air quality standards. Ambient ozone was titrated by NO in the dark, dense core of the smoke plume close to the fires, and photochemical ozone production was limited to the diffuse edge of the plume. Photochemical O{sub 3} production was noted throughout the plume at a distance of 160 km downwind of Kuwait City, and averaged 2.3 ppbv per hour during the first 3 hours of transport. Little additional photochemical production was noted at a downwind range of 340 km. The fluxes of sulfur dioxide, carbon monoxide, and reactive nitrogen from the roughly 520 fires still burning on May 30, 1991 are estimated at 1.4 x 10{sup 7} kg SO{sub 2}/d, 6.9 x 10{sup 6} kg CO/d, and 2.7 x 10{sup 5} kg N/d, respectively. Generally low concentrations of CO and NO{sub x} indicate that the combustion was efficient and occurred at low temperatures. Low total nonmethane hydrocarbon concentrations suggest that the volatile components of the petroleum were burned efficiently. 37 refs., 4 figs., 4 tabs.

  4. Modelling concentrations of volcanic ash encountered by aircraft in past eruptions

    NASA Astrophysics Data System (ADS)

    Witham, Claire; Webster, Helen; Hort, Matthew; Jones, Andrew; Thomson, David

    2012-03-01

    Prolonged disruption to aviation during the April-May 2010 eruption of Eyjafjallajökull, Iceland resulted in pressure to predict volcanic ash plume concentrations for the purpose of allowing aircraft to fly in regions with low ash contamination. Over the past few decades there have been a number of incidents where aircraft have encountered volcanic ash resulting in damage to the aircraft and loss of power to engines. Understanding the volcanic ash concentrations that these aircraft have encountered provides important input to determining a safe concentration limit. Aircraft encounters with six volcanic eruption plumes have been studied and ash concentrations predicted using the atmospheric dispersion model NAME. The eruptions considered are Galunggung 1982, Soputan 1985, Redoubt 1989, Pinatubo 1991, Hekla 2000 and Manam 2006. Uncertainties in the eruption source details (start time, stop time and eruption height) and in the aircraft encounter location and flight path are found to be major limitations in some cases. Errors in the driving meteorological data (which is often coarse in resolution for historic studies) and the lack of eruption plume dynamics (e.g. umbrella cloud representation) results in further uncertainties in the predicted ash concentrations. In most of the case studies, the dispersion modelling shows the presence of ash at the aircraft encounter location. Maximum ash concentrations in the vicinity of the aircraft are predicted to be at least 4000 μg m -3 although confidence in the estimated concentrations is low and uncertainties of orders of magnitude are shown to be possible.

  5. THE STRUCTURE AND ORIGIN OF SOLAR PLUMES: NETWORK PLUMES

    SciTech Connect

    Gabriel, A.; Tison, E.; Bely-Dubau, F.; Wilhelm, K.

    2009-07-20

    This study is based upon plumes seen close to the solar limb within coronal holes in the emission from ions formed in the temperature region of 1 MK, in particular, the band of Fe IX 171 A from EIT on the Solar and Heliospheric Observatory. It is shown, using geometric arguments, that two distinct classes of structure contribute to apparently similar plume observations. Quasi-cylindrical structures are anchored in discrete regions of the solar surface (beam plumes), and faint extended structures require integration along the line of sight (LOS) in order to reproduce the observed brightness. This second category, sometimes called 'curtains', are ubiquitous within the polar holes and are usually more abundant than the beam plumes, which depend more on the enhanced magnetic structures detected at their footpoints. It is here proposed that both phenomena are based on plasma structures in which emerging magnetic loops interact with ambient monopolar fields, involving reconnection. The important difference is in terms of physical scale. It is proposed that curtains are composed of a large number of microplumes, distributed along the LOS. The supergranule network provides the required spatial structure. It is shown by modeling that the observations can be reproduced if microplumes are concentrated within some 5 Mm of the cell boundaries. For this reason, we propose to call this second population 'network plumes'. The processes involved could represent a major contribution to the heating mechanism of the solar corona.

  6. 14 CFR 27.1123 - Exhaust piping.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Exhaust piping. 27.1123 Section 27.1123... STANDARDS: NORMAL CATEGORY ROTORCRAFT Powerplant Exhaust System § 27.1123 Exhaust piping. (a) Exhaust piping... operating temperatures. (b) Exhaust piping must be supported to withstand any vibration and inertia loads...

  7. 14 CFR 29.1123 - Exhaust piping.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Exhaust piping. 29.1123 Section 29.1123... STANDARDS: TRANSPORT CATEGORY ROTORCRAFT Powerplant Exhaust System § 29.1123 Exhaust piping. (a) Exhaust... by operating temperatures. (b) Exhaust piping must be supported to withstand any vibration...

  8. Automotive Fuel and Exhaust Systems.

    ERIC Educational Resources Information Center

    Irby, James F.; And Others

    Materials are provided for a 14-hour course designed to introduce the automotive mechanic to the basic operations of automotive fuel and exhaust systems incorporated on military vehicles. The four study units cover characteristics of fuels, gasoline fuel system, diesel fuel systems, and exhaust system. Each study unit begins with a general…

  9. Treatment of power utilities exhaust

    DOEpatents

    Koermer, Gerald

    2012-05-15

    Provided is a process for treating nitrogen oxide-containing exhaust produced by a stationary combustion source by the catalytic reduction of nitrogen oxide in the presence of a reductant comprising hydrogen, followed by ammonia selective catalytic reduction to further reduce the nitrogen oxide level in the exhaust.

  10. Assessing and controlling the effect of aircraft on the environment: Pollution

    NASA Technical Reports Server (NTRS)

    Poppoff, I. G.; Grobman, J. S.

    1975-01-01

    The air pollution created by aircraft engines around airports and the global atmospheric problem of supersonic aircraft operating in the stratosphere are discussed. Methods for assessing the air pollution impact are proposed. The use of atmospheric models to determine the air pollution extent is described. Methods for controlling the emissions of aircraft engines are examined. Diagrams of the atmospheric composition resulting from exhaust gas emissions are developed.

  11. Distributed Exhaust Nozzles for Jet Noise Reduction

    NASA Technical Reports Server (NTRS)

    Ahuja, K. K.; Gaeta, R. J.; Hellman, B.; Schein, D. B.; Solomon, W. D., Jr.; Huff, Dennis (Technical Monitor)

    2001-01-01

    The main objective of this study is to validate the jet noise reduction potential of a concept associated with distributed exhaust nozzles. Under this concept the propulsive thrust is generated by a larger number of discrete plumes issuing from an array of small or mini-nozzles. The potential of noise reduction of this concept stems from the fact that a large number of small jets will produce very high frequency noise and also, if spaced suitably, they will coalesce at a smaller velocity to produce low amplitude, low frequency noise. This is accomplished through detailed acoustic and fluid measurements along with a Computational Fluidic Dynamic (CFD) solution of the mean (DE) Distributed Exhaust nozzle flowfield performed by Northrop-Grumman. The acoustic performance is quantified in an anechoic chamber. Farfield acoustic data is acquired for a DE nozzle as well as a round nozzle of the same area. Both these types of nozzles are assessed numerically using Computational Fluid Dynamic (CFD) techniques. The CFD analysis ensures that both nozzles issued the same amount of airflow for a given nozzle pressure ratio. Data at a variety of nozzle pressure ratios are acquired at a range of polar and azimuthal angles. Flow visualization of the DE nozzle is used to assess the fluid dynamics of the small jet interactions. Results show that at high subsonic jet velocities, the DE nozzle shifts its frequency of peak amplitude to a higher frequency relative to a round nozzle of equivalent area (from a S(sub tD) = 0.24 to 1. 3). Furthermore, the DE nozzle shows reduced sound pressure levels (as much as 4 - 8 dB) in the low frequency part of the spectrum (less than S(sub tD) = 0.24 ) compared to the round nozzle. At supersonic jet velocities, the DE nozzle does not exhibit the jet screech and the shock-associated broadband noise is reduced by as much as 12 dB.

  12. The NASA research program on propulsion for supersonic cruise aircraft

    NASA Technical Reports Server (NTRS)

    Weber, R. J.

    1975-01-01

    The objectives and status of the propulsion portion of a program aimed at advancing the technology and establishing a data base appropriate for the possible future development of supersonic cruise aircraft are reviewed. Research related to exhaust nozzles, combustors, and inlets that is covered by the noise, pollution, and dynamics programs is described.

  13. Subsonic Jet Noise Reduced With Improved Internal Exhaust Gas Mixers

    NASA Technical Reports Server (NTRS)

    1996-01-01

    Aircraft noise pollution is becoming a major environmental concern for the world community. The Federal Aviation Administration (FAA) is responding to this concern by imposing more stringent noise restrictions for aircraft certification then ever before to keep the U.S. industry competitive with the rest of the world. At the NASA Lewis Research Center, attempts are underway to develop noise-reduction technology for newer engines and for retrofitting existing engines so that they are as quiet as (or quieter than) required. Lewis conducted acoustic and Laser Doppler Velocimetry (LDV) tests using Pratt & Whitney's Internal Exhaust Gas Mixers (IEGM). The IEGM's mix the core flow with the fan flow prior to their common exhaust. All tests were conducted in Lewis' Aero-Acoustic Propulsion Laboratory--a semihemispheric dome open to the ambient atmosphere. This was the first time Laser Doppler Velocimetry was used in such a facility at Lewis. Jet exhaust velocity and turbulence and the internal velocity fields were detailed. Far-field acoustics were also measured. Pratt & Whitney provided 1/7th scale model test hardware (a 12-lobe mixer, a 20-lobe mixer, and a splitter) for 1.7 bypass ratio engines, and NASA provided the research engineers, test facility, and test time. The Pratt & Whitney JT8D-200 engine power conditions were used for all tests.

  14. Exhaust Nozzle Materials Development for the High Speed Civil Transport

    NASA Technical Reports Server (NTRS)

    Grady, J. E.

    1999-01-01

    The United States has embarked on a national effort to develop the technology necessary to produce a Mach 2.4 High Speed Civil Transport (HSCT) for entry into service by the year 2005. The viability of this aircraft is contingent upon its meeting both economic and environmental requirements. Two engine components have been identified as critical to the environmental acceptability of the HSCT. These include a combustor with significantly lower emissions than are feasible with current technology, and a lightweight exhaust nozzle that meets community noise standards. The Enabling Propulsion Materials (EPM) program will develop the advanced structural materials, materials fabrication processes, structural analysis and life prediction tools for the HSCT combustor and low noise exhaust nozzle. This is being accomplished through the coordinated efforts of the NASA Lewis Research Center, General Electric Aircraft Engines and Pratt & Whitney. The mission of the EPM Exhaust Nozzle Team is to develop and demonstrate this technology by the year 1999 to enable its timely incorporation into HSCT propulsion systems.

  15. DOAS measurements of NO2 from an ultralight aircraft during the Earth Challenge expedition

    NASA Astrophysics Data System (ADS)

    Merlaud, A.; van Roozendael, M.; van Gent, J.; Fayt, C.; Maes, J.; Toledo, X.; Ronveaux, O.; de Mazière, M.

    2012-02-01

    We report on airborne Differential Optical Absorption Spectroscopy (DOAS) measurements of NO2 tropospheric columns above South Asia, Arabic peninsula, North Africa, and Italy in November and December 2009. The DOAS instrument was installed on an ultralight aircraft involved in the Earth Challenge project, an expedition of seven pilots flying on four ultralight aircraft between Australia and Belgium. The instrument recorded spectra in limb geometry with a large field-of-view, a set-up which provides a high sensitivity to the boundary layer NO2 while minimizing the uncertainties related to the attitude variations. We compare our measurements with OMI and GOME-2 tropospheric NO2 products when the latter are available. Above Rajasthan and the Po Valley, two areas where the NO2 field is homogeneous, data sets agree very well. Our measurements in this areas are respectively 0.1 ± 0.1 to 2.8 ± 1 × 1015 molec cm-2 and 2.5 ± 0.5 × 1016 molec cm-2. Flying downwind of Riyadh, our NO2 measurements show with a higher spatial resolution than OMI the structure of the megacities'exhaust plume. Moreover, our measurements indicate larger columns (up to 70%) than the one seen by satellites. We also derived tropopsheric columns when no satellite data was available, if it was possible to get information on the visibility from satellite measurements of aerosol optical thickness. The maximum column we measured was above Benghazi, with 5.7 ± 2 × 1016 molec cm-2. This experiment also provides a confirmation for the recent finding of a soil signature above desert.

  16. DOAS measurements of NO2 from an ultralight aircraft during the Earth Challenge expedition

    NASA Astrophysics Data System (ADS)

    Merlaud, A.; Van Roozendael, M.; van Gent, J.; Fayt, C.; Maes, J.; Toledo-Fuentes, X.; Ronveaux, O.; De Mazière, M.

    2012-08-01

    We report on airborne Differential Optical Absorption Spectroscopy (DOAS) measurements of NO2 tropospheric columns above South Asia, the Arabic peninsula, North Africa, and Italy in November and December 2009. The DOAS instrument was installed on an ultralight aircraft involved in the Earth Challenge project, an expedition of seven pilots flying on four ultralight aircraft between Australia and Belgium. The instrument recorded spectra in limb geometry with a large field of view, a set-up which provides a high sensitivity to the boundary layer NO2 while minimizing the uncertainties related to the attitude variations. We compare our measurements with OMI (Ozone Monitoring Instrument) and GOME-2 (Global Ozone Monitoring Experiment 2) tropospheric NO2 products when the latter are available. Above Rajasthan and the Po Valley, two areas where the NO2 field is homogeneous, data sets agree very well. Our measurements in these areas are 0.1 ± 0.1 to 3 ± 1 × 1015 molec cm-2 and 2.6 ± 0.8 × 1016 molec cm-2, respectively. Flying downwind of Riyadh, our NO2 measurements show the structure of the megacity's exhaust plume with a higher spatial resolution than OMI. Moreover, our measurements are larger (up to 40%) than those seen by satellites. We also derived tropospheric columns when no satellite data were available if it was possible to get information on the visibility from satellite measurements of aerosol optical thickness. This experiment also provides a confirmation for the recent finding of a soil signature above desert.

  17. 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.

  18. Laser induced fluorescence measurements of the cylindrical Hall thruster plume

    SciTech Connect

    Spektor, R.; Diamant, K. D.; Beiting, E. J.; Raitses, Y.; Fisch, N. J.

    2010-09-15

    An investigation of a fully cylindrical Hall thruster was performed using laser induced fluorescence (LIF) to measure ion velocity profiles in the plume. The measurements confirm a previously reported 9% increase in the exhaust energy when the cathode keeper draws an excess current (overrun mode). Furthermore, the velocity directions in the plume remain relatively unchanged for the cusped and direct magnetic field configuration in both overrun and nonoverrun modes. Previously reported plume narrowing in the overrun mode was confirmed and found to be due to the shift of the acceleration and ionization regions toward the anode. The electric field inferred from the LIF measurements allowed calculation of the electron ExB drift. Close to the centerline of the thruster, electrons drift azimuthally with velocity decreasing away from the centerline, thus creating shear. This shear can be a source of plasma instabilities and influence electron transport. Further away from the centerline, electrons drift in the opposite direction with their velocity increasing with increasing radius. In that region, electrons rotate without shear.

  19. Aircraft Electric Secondary Power

    NASA Technical Reports Server (NTRS)

    1983-01-01

    Technologies resulted to aircraft power systems and aircraft in which all secondary power is supplied electrically are discussed. A high-voltage dc power generating system for fighter aircraft, permanent magnet motors and generators for aircraft, lightweight transformers, and the installation of electric generators on turbine engines are among the topics discussed.

  20. World commercial aircraft accidents

    SciTech Connect

    Kimura, C.Y.

    1993-01-01

    This report is a compilation of all accidents world-wide involving aircraft in commercial service which resulted in the loss of the airframe or one or more fatality, or both. This information has been gathered in order to present a complete inventory of commercial aircraft accidents. Events involving military action, sabotage, terrorist bombings, hijackings, suicides, and industrial ground accidents are included within this list. Included are: accidents involving world commercial jet aircraft, world commercial turboprop aircraft, world commercial pistonprop aircraft with four or more engines and world commercial pistonprop aircraft with two or three engines from 1946 to 1992. Each accident is presented with information in the following categories: date of the accident, airline and its flight numbers, type of flight, type of aircraft, aircraft registration number, construction number/manufacturers serial number, aircraft damage, accident flight phase, accident location, number of fatalities, number of occupants, cause, remarks, or description (brief) of the accident, and finally references used. The sixth chapter presents a summary of the world commercial aircraft accidents by major aircraft class (e.g. jet, turboprop, and pistonprop) and by flight phase. The seventh chapter presents several special studies including a list of world commercial aircraft accidents for all aircraft types with 100 or more fatalities in order of decreasing number of fatalities, a list of collision accidents involving commercial aircrafts, and a list of world commercial aircraft accidents for all aircraft types involving military action, sabotage, terrorist bombings, and hijackings.

  1. 40 CFR 87.82 - Sampling and analytical procedures for measuring smoke exhaust emissions.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... measuring smoke exhaust emissions. 87.82 Section 87.82 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) Definitions. Test Procedures for Engine Smoke Emissions (Aircraft Gas Turbine Engines) § 87.82 Sampling and analytical procedures for measuring smoke...

  2. Tomographic reconstruction of polar plumes

    NASA Astrophysics Data System (ADS)

    Auchère, F.; Guennou, C.; Barbey, N.

    2012-06-01

    We present a tomographic reconstruction of polar plumes as observed in the Extreme Ultraviolet in January 2010. Plumes are elusive structures visible in polar coronal holes that may play an important role in the acceleration of the solar wind. However, despite numerous observations, little is irrefutably known about them. Because of line of sight effects, even their geometry is subject to debate. Are they genuine cylindrical features of the corona or are they only chance alignments along the line of sight? Tomography provides a means to reconstruct the volume of an optically thin object from a set of observations taken from different vantage points. In the case of the Sun, these are typically obtained by using a solar rotation worth of images, which limits the ability to reconstruct short lived structures. We present here a tomographic inversion of the solar corona obtained using only 6 days of data. This is achieved by using simultaneously three space telescopes (EUVI/STEREO and SWAP/PROBA2) in a very specific orbital configuration. The result is the shortest possible tomographic snapshot of polar plumes. The 3D reconstruction shows both quasi-cylindrical plumes and a network pattern that can mimic them by line of sight superimpositions. This suggests that the controversy on plume geometry is due to the coexistence of both types of structures.

  3. Stationary Plasma Thruster Plume Characteristics

    NASA Technical Reports Server (NTRS)

    Myers, Roger M.; Manzella, David H.

    1994-01-01

    Stationary Plasma Thrusters (SPT's) are being investigated for application to a variety of near-term missions. This paper presents the results of a preliminary study of the thruster plume characteristics which are needed to assess spacecraft integration requirements. Langmuir probes, planar probes, Faraday cups, and a retarding potential analyzer were used to measure plume properties. For the design operating voltage of 300 V the centerline electron density was found to decrease from approximately 1.8 x 10 exp 17 cubic meters at a distance of 0.3 m to 1.8 X 10 exp 14 cubic meters at a distance of 4 m from the thruster. The electron temperature over the same region was between 1.7 and 3.5 eV. Ion current density measurements showed that the plume was sharply peaked, dropping by a factor of 2.6 within 22 degrees of centerline. The ion energy 4 m from the thruster and 15 degrees off-centerline was approximately 270 V. The thruster cathode flow rate and facility pressure were found to strongly affect the plume properties. In addition to the plume measurements, the data from the various probe types were used to assess the impact of probe design criteria

  4. Numerical modeling of exhaust smoke dispersion for a generic frigate and comparisons with experiments

    NASA Astrophysics Data System (ADS)

    Ergin, Selma; Dobrucalı, Erinç

    2014-06-01

    The exhaust smoke dispersion for a generic frigate is investigated numerically through the numerical solution of the governing fluid flow, energy, species and turbulence equations. The main objective of this work is to obtain the effects of the yaw angle, velocity ratio and buoyancy on the dispersion of the exhaust smoke. The numerical method is based on the fully conserved control-volume representation of the fully elliptic Navier-Stokes equations. Turbulence is modeled using a two-equation ( k- ɛ) model. The flow visualization tests using a 1/100 scale model of the frigate in the wind tunnel were also carried out to determine the exhaust plume path and to validate the computational results. The results show that down wash phenomena occurs for the yaw angles between ψ =10° and 20°. The results with different exhaust gas temperatures show that the buoyancy effect increases with the increasing of the exhaust gas temperature. However, its effect on the plume rise is less significant in comparison with its momentum. A good agreement between the predictions and experiment results is obtained.

  5. Large-eddy simulation of turbulence in the free atmosphere and behind aircraft

    NASA Astrophysics Data System (ADS)

    Schumann, U.; Dörnbrack, A.; Dürbeck, T.; Gerz, T.

    1997-02-01

    The method of large-eddy simulation has been used for a wide variety of atmospheric flow problems. This paper gives an overview on recent applications of this method to turbulence in the free atmosphere under stably stratified conditions. In particular, flows in the wake of aircraft are studied in light of the potential impact of aircraft exhausts on the chemical and climatological state of the atmosphere. It is shown that different profiles of heat and moisture in the initial conditions of a jet representing engine exhaust gases may cause larger water saturation and hence earlier contrail formation than assumed up to now. The instability of trailing vortices in the wake of an aircraft is simulated up to the fully turbulent regime. The vertical diffusivity of aircraft exhaust is large in the vortex regime and much smaller than horizontal diffusivities in the later diffusion regime. The three-dimensional formation of a critical layer and breaking of gravity waves is simulated.

  6. GASOLINE VEHICLE EXHAUST PARTICLE SAMPLING STUDY

    SciTech Connect

    Kittelson, D; Watts, W; Johnson, J; Zarling, D Schauer,J Kasper, K; Baltensperger, U; Burtscher, H

    2003-08-24

    The University of Minnesota collaborated with the Paul Scherrer Institute, the University of Wisconsin (UWI) and Ricardo, Inc to physically and chemically characterize the exhaust plume from recruited gasoline spark ignition (SI) vehicles. The project objectives were: (1) Measure representative particle size distributions from a set of on-road SI vehicles and compare these data to similar data collected on a small subset of light-duty gasoline vehicles tested on a chassis dynamometer with a dilution tunnel using the Unified Drive Cycle, at both room temperature (cold start) and 0 C (cold-cold start). (2) Compare data collected from SI vehicles to similar data collected from Diesel engines during the Coordinating Research Council E-43 project. (3) Characterize on-road aerosol during mixed midweek traffic and Sunday midday periods and determine fleet-specific emission rates. (4) Characterize bulk- and size-segregated chemical composition of the particulate matter (PM) emitted in the exhaust from the gasoline vehicles. Particle number concentrations and size distributions are strongly influenced by dilution and sampling conditions. Laboratory methods were evaluated to dilute SI exhaust in a way that would produce size distributions that were similar to those measured during laboratory experiments. Size fractionated samples were collected for chemical analysis using a nano-microorifice uniform deposit impactor (nano-MOUDI). In addition, bulk samples were collected and analyzed. A mixture of low, mid and high mileage vehicles were recruited for testing during the study. Under steady highway cruise conditions a significant particle signature above background was not measured, but during hard accelerations number size distributions for the test fleet were similar to modern heavy-duty Diesel vehicles. Number emissions were much higher at high speed and during cold-cold starts. Fuel specific number emissions range from 1012 to 3 x 1016 particles/kg fuel. A simple

  7. Lidar sounding of volcanic plumes

    NASA Astrophysics Data System (ADS)

    Fiorani, Luca; Aiuppa, Alessandro; Angelini, Federico; Borelli, Rodolfo; Del Franco, Mario; Murra, Daniele; Pistilli, Marco; Puiu, Adriana; Santoro, Simone

    2013-10-01

    Accurate knowledge of gas composition in volcanic plumes has high scientific and societal value. On the one hand, it gives information on the geophysical processes taking place inside volcanos; on the other hand, it provides alert on possible eruptions. For this reasons, it has been suggested to monitor volcanic plumes by lidar. In particular, one of the aims of the FP7 ERC project BRIDGE is the measurement of CO2 concentration in volcanic gases by differential absorption lidar. This is a very challenging task due to the harsh environment, the narrowness and weakness of the CO2 absorption lines and the difficulty to procure a suitable laser source. This paper, after a review on remote sensing of volcanic plumes, reports on the current progress of the lidar system.

  8. A Survey of Challenges in Aerodynamic Exhaust Nozzle Technology for Aerospace Propulsion Applications

    NASA Technical Reports Server (NTRS)

    Shyne, Rickey J.

    2002-01-01

    The current paper discusses aerodynamic exhaust nozzle technology challenges for aircraft and space propulsion systems. Technology advances in computational and experimental methods have led to more accurate design and analysis tools, but many major challenges continue to exist in nozzle performance, jet noise and weight reduction. New generations of aircraft and space vehicle concepts dictate that exhaust nozzles have optimum performance, low weight and acceptable noise signatures. Numerous innovative nozzle concepts have been proposed for advanced subsonic, supersonic and hypersonic vehicle configurations such as ejector, mixer-ejector, plug, single expansion ramp, altitude compensating, lobed and chevron nozzles. This paper will discuss the technology barriers that exist for exhaust nozzles as well as current research efforts in place to address the barriers.

  9. Observations of volatile organic compounds during ARCTAS - Part 1: Biomass burning emissions and plume enhancements

    NASA Astrophysics Data System (ADS)

    Hornbrook, R. S.; Blake, D. R.; Diskin, G. S.; Fuelberg, H. E.; Meinardi, S.; Mikoviny, T.; Sachse, G. W.; Vay, S. A.; Weinheimer, A. J.; Wiedinmyer, C.; Wisthaler, A.; Hills, A.; Riemer, D. D.; Apel, E. C.

    2011-05-01

    Mixing ratios of a large number of volatile organic compounds (VOCs) were observed by the Trace Organic Gas Analyzer (TOGA) on board the NASA DC-8 as part of the Arctic Research of the Composition of the Troposphere from Aircraft and Satellites (ARCTAS) field campaign. Many of these VOCs were observed concurrently by one or both of two other VOC measurement techniques on board the DC-8: proton-transfer-reaction mass spectrometry (PTR-MS) and whole air canister sampling (WAS). A comparison of these measurements to the data from TOGA indicates good agreement for the majority of co-measured VOCs. The ARCTAS study, which included both spring and summer deployments, provided opportunities to sample a large number of biomass burning (BB) plumes with origins in Asia, California and Central Canada, ranging from very recent emissions to plumes aged one week or more. For this analysis, identified BB plumes were grouped by flight, source region and, in some cases, time of day, generating 40 individual plume groups, each consisting of one or more BB plume interceptions. Normalized excess mixing ratios (EMRs) to CO were determined for each of the 40 plume groups for up to 19 different VOCs or VOC groups, many of which show significant variability, even within relatively fresh plumes. This variability demonstrates the importance of assessing BB plumes both regionally and temporally, as emissions can vary from region to region, and even within a fire over time. Comparisons with literature confirm that variability of EMRs to CO over an order of magnitude for many VOCs is consistent with previous observations. However, this variability is often diluted in the literature when individual observations are averaged to generate an overall regional EMR from a particular study. Previous studies give the impression that emission ratios are generally consistent within a given region, and this is not necessarily the case, as our results show. For some VOCs, earlier assumptions may lead to

  10. Summary of Experiments Performed to Investigate the Effects of Ion Thruster Plumes on Microwave Propagation

    NASA Technical Reports Server (NTRS)

    Lambert, Kevin M.; Zaman, Afroz J.

    1999-01-01

    Electric propulsion systems have now reached a level of maturity where they are being used on operational spacecraft. One concern for the designers however, is the effect of the ion exhaust plumes produced by the systems, on microwave communication with the spacecraft. To better understand these effects, a number of propagation experiments were performed at the NASA Glenn Research Center with an operating ion thruster. This report describes the experiments and presents the results of the data obtained.

  11. Modeling Leaking Gas Plume Migration

    SciTech Connect

    Silin, Dmitriy; Patzek, Tad; Benson, Sally M.

    2007-08-20

    In this study, we obtain simple estimates of 1-D plume propagation velocity taking into account the density and viscosity contrast between CO{sub 2} and brine. Application of the Buckley-Leverett model to describe buoyancy-driven countercurrent flow of two immiscible phases leads to a transparent theory predicting the evolution of the plume. We obtain that the plume does not migrate upward like a gas bubble in bulk water. Rather, it stretches upward until it reaches a seal or until the fluids become immobile. A simple formula requiring no complex numerical calculations describes the velocity of plume propagation. This solution is a simplification of a more comprehensive theory of countercurrent plume migration that does not lend itself to a simple analytical solution (Silin et al., 2006). The range of applicability of the simplified solution is assessed and provided. This work is motivated by the growing interest in injecting carbon dioxide into deep geological formations as a means of avoiding its atmospheric emissions and consequent global warming. One of the potential problems associated with the geologic method of sequestration is leakage of CO{sub 2} from the underground storage reservoir into sources of drinking water. Ideally, the injected green-house gases will stay in the injection zone for a geologically long time and eventually will dissolve in the formation brine and remain trapped by mineralization. However, naturally present or inadvertently created conduits in the cap rock may result in a gas leak from primary storage. Even in supercritical state, the carbon dioxide viscosity and density are lower than those of the indigenous formation brine. Therefore, buoyancy will tend to drive the CO{sub 2} upward unless it is trapped beneath a low permeability seal. Theoretical and experimental studies of buoyancy-driven supercritical CO{sub 2} flow, including estimation of time scales associated with plume evolution, are critical for developing technology

  12. Simulation of Europa's water plume .

    NASA Astrophysics Data System (ADS)

    Lucchetti, A.; Cremonese, G.; Schneider, N. M.; Plainaki, C.; Mazzotta Epifani, E.; Zusi, M.; Palumbo, P.

    Plumes on Europa would be extremely interesting science and mission targets, particularly due to the unique opportunity to obtain direct information on the subsurface composition, thereby addressing Europa's potential habitability. The existence of water plume on the Jupiter's moon Europa has been long speculated until the recent discover. HST imaged surpluses of hydrogen Lyman alpha and oxygen emissions above the southern hemisphere in December 2012 that are consistent with two 200 km high plumes of water vapor (Roth et al. 2013). In previous works ballistic cryovolcanism has been considered and modeled as a possible mechanism for the formation of low-albedo features on Europa's surface (Fagents et al. 2000). Our simulation agrees with the model of Fagents et al. (2000) and consists of icy particles that follow ballistic trajectories. The goal of such an analysis is to define the height, the distribution and the extension of the icy particles falling on the moon's surface as well as the thickness of the deposited layer. We expect to observe high albedo regions in contrast with the background albedo of Europa surface since we consider that material falling after a cryovolcanic plume consists of snow. In order to understand if this phenomenon is detectable we convert the particles deposit in a pixel image of albedo data. We consider also the limb view of the plume because, even if this detection requires optimal viewing geometry, it is easier detectable in principle against sky. Furthermore, we are studying the loss rates due to impact electron dissociation and ionization to understand how these reactions decrease the intensity of the phenomenon. We expect to obtain constraints on imaging requirements necessary to detect potential plumes that could be useful for ESA's JUICE mission, and in particular for the JANUS camera (Palumbo et al. 2014).

  13. Effect of contamination on the optical properties of transmitting and reflecting materials exposed to a MMH/N2O4 rocket exhaust

    NASA Technical Reports Server (NTRS)

    Bowman, R. L.; Spisz, E. W.; Jack, J. R.

    1973-01-01

    The changes are presented in spectral transmittance, and reflectance due to exposure of various optical materials to the exhaust plume of a 5-pound thrust bipropellant rocket. The engine was fired in a pulsed mode for a total exposure of 223.7 second. Spectral optical properties were measured in air before and after exposure to the exhaust plume in vacuum. The contaminating layer resulted in both absorption and scattering effects which caused changes as large as 30-50% for transmitting elements and 15% for mirrors in the near ultraviolet wavelengths. The changes in spectral properties of materials exposed to the exhaust plume for 44 and 223.7 seconds are compared and found to be similar.

  14. Aerodynamics of powered missile separation from F/A-18 aircraft

    NASA Technical Reports Server (NTRS)

    Ahmad, J. U.; Shanks, S. P.; Buning, P. G.

    1993-01-01

    A 3D dynamic 'chimera' algorithm that solves the thin-layer Navier-Stokes equations over multiple moving bodies was modified to numerically simulate the aerodynamics, missile dynamics, and missile plume interactions of a missile separating from a generic wing and from an F/A-18 aircraft in transonic flow. The missile is mounted below the wing for missile separation from the wing and on the F/A-18 fuselage at the engine inlet side for missile separation from aircraft. Static and powered missile separation cases are considered to examine the influence of the missile and plume on the wing and F/A-18 fuselage and engine inlet. The aircraft and missile are at two degrees angle of attack, Reynolds number of 10 million, freestream Mach number of 1.05 and plume Mach number of 3.0. The computational results show the details of the flow field.

  15. Mobile Bay turbidity plume study

    NASA Technical Reports Server (NTRS)

    Crozier, G. F.

    1976-01-01

    Laboratory and field transmissometer studies on the effect of suspended particulate material upon the appearance of water are reported. Quantitative correlations were developed between remotely sensed image density, optical sea truth data, and actual sediment load. Evaluation of satellite image sea truth data for an offshore plume projects contours of transmissivity for two different tidal phases. Data clearly demonstrate the speed of change and movement of the optical plume for water patterns associated with the mouth of Mobile bay in which relatively clear Gulf of Mexico water enters the bay on the eastern side. Data show that wind stress in excess of 15 knots has a marked impact in producing suspended sediment loads.

  16. POD Analysis of Jet-Plume/Afterbody-Wake Interaction

    NASA Astrophysics Data System (ADS)

    Murray, Nathan E.; Seiner, John M.; Jansen, Bernard J.; Gui, Lichuan; Sockwell, Shuan; Joachim, Matthew

    2009-11-01

    The understanding of the flow physics in the base region of a powered rocket is one of the keys to designing the next generation of reusable launchers. The base flow features affect the aerodynamics and the heat loading at the base of the vehicle. Recent efforts at the National Center for Physical Acoustics at the University of Mississippi have refurbished two models for studying jet-plume/afterbody-wake interactions in the NCPA's 1-foot Tri-Sonic Wind Tunnel Facility. Both models have a 2.5 inch outer diameter with a nominally 0.5 inch diameter centered exhaust nozzle. One of the models is capable of being powered with gaseous H2 and O2 to study the base flow in a fully combusting senario. The second model uses hi-pressure air to drive the exhaust providing an unheated representative flow field. This unheated model was used to acquire PIV data of the base flow. Subsequently, a POD analysis was performed to provide a first look at the large-scale structures present for the interaction between an axisymmetric jet and an axisymmetric afterbody wake. PIV and Schlieren data are presented for a single jet-exhaust to free-stream flow velocity along with the POD analysis of the base flow field.

  17. Airborne radiological sampling of Mount St. Helens plumes

    SciTech Connect

    Andrews, V.E.

    1981-04-01

    Particulate and gaseous samples for radiologial analyses were collected from the plumes created by eruptions of Mount St. Helens. The sampling aircraft and equipment used are routinely employed in aerial radiological surveillance at the Nevada Test Site by the Environmental Protection Agency's Environmental Monitoring Systems Laboratory in Las Vegas, Nevada. An initial sample set was collected on April 4, 1980, during the period of recurring minor eruptions. Samples were collected again on May 19 and 20 following the major eruption of May 18. The Environmental Protection Agency's Office of Radiation Programs analyzed the samples for uranium and thorium isotopes, radium-226, lead-210, polonium-210, and radon-222. Other laboratories analyzed samples to determine particle size distribution and elemental composition. The only samples containing radioactivity above normal ambient levels were collected on May 20. Polonium-210 concentrations in the plume, determined from a sample collected between 5 and 30 km from the crater, were approximately an order of magnitude above background. Radon-222 concentrations in samples collected from the plume centerline at a distance of 15 km averaged approximately four times the average surface concentrations. The small increases in radioactivity would cause no observable adverse health effects.

  18. Effect of water to ablative performance under solid rocket exhaust environment

    NASA Astrophysics Data System (ADS)

    Miller, M. J.; Koo, J. H.; Sickler, F. M.; Lecureux, F.; Dash, S. M.

    1993-06-01

    The local environment during a missile firing is particularly hostile. Thermal protection of the missile launcher structure is often achieved with ablatives. Ablatives erode when subjected to high-temperature rocket exhaust, but the backside temperature of the protected structure remains relatively cool due to the insulative nature of ablatives. Multiple missile firings can completely erode the ablative, exposing the launching system components to an extremely high temperature. This investigation addresses the concept of injecting water into the missile plume to reduce the amount of ablative erosion per missile firing. This concept also reduces the amount of ablative materials needed in missile launching systems. Injecting water into the exhaust plume in a controlled laboratory environment was performed. Heat flux and material erosion measurements were compared in this study.

  19. Air pollution from aircraft. [jet exhaust - aircraft fuels/combustion efficiency

    NASA Technical Reports Server (NTRS)

    Heywood, J. B.; Chigier, N. A.

    1975-01-01

    A model which predicts nitric oxide and carbon monoxide emissions from a swirl can modular combustor is discussed. A detailed analysis of the turbulent fuel-air mixing process in the swirl can module wake region is reviewed. Hot wire anemometry was employed, and gas sampling analysis of fuel combustion emissions were performed.

  20. Underexpanded Supersonic Plume Surface Interactions: Applications for Spacecraft Landings on Planetary Bodies

    NASA Technical Reports Server (NTRS)

    Mehta, M.; Sengupta, A.; Renno, N. O.; Norman, J. W.; Gulick, D. S.

    2011-01-01

    Numerical and experimental investigations of both far-field and near-field supersonic steady jet interactions with a flat surface at various atmospheric pressures are presented in this paper. These studies were done in assessing the landing hazards of both the NASA Mars Science Laboratory and Phoenix Mars spacecrafts. Temporal and spatial ground pressure measurements in conjunction with numerical solutions at altitudes of approx.35 nozzle exit diameters and jet expansion ratios (e) between 0.02 and 100 are used. Data from steady nitrogen jets are compared to both pulsed jets and rocket exhaust plumes at Mach approx.5. Due to engine cycling, overpressures and the plate shock dynamics are different between pulsed and steady supersonic impinging jets. In contrast to highly over-expanded (e <1) and underexpanded exhaust plumes, results show that there is a relative ground pressure load maximum for moderately underexpanded (e approx.2-5) jets which demonstrate a long collimated plume shock structure. For plumes with e much >5 (lunar atmospheric regime), the ground pressure is minimal due to the development of a highly expansive shock structure. We show this is dependent on the stability of the plate shock, the length of the supersonic core and plume decay due to shear layer instability which are all a function of the jet expansion ratio. Asymmetry and large gradients in the spatial ground pressure profile and large transient overpressures are predominantly linked to the dynamics of the plate shock. More importantly, this study shows that thruster plumes exhausting into martian environments possess the largest surface pressure loads and can occur at high spacecraft altitudes in contrast to the jet interactions at terrestrial and lunar atmospheres. Theoretical and analytical results also show that subscale supersonic cold gas jets adequately simulate the flow field and loads due to rocket plume impingement provided important scaling parameters are in agreement. These