These are representative sample records from Science.gov related to your search topic.
For comprehensive and current results, perform a real-time search at Science.gov.
1

Aviation-fuel property effects on combustion  

NASA Technical Reports Server (NTRS)

The fuel chemical property influence on a gas turbine combustor was studied using 25 test fuels. Fuel physical properties were de-emphasized by using fuel injectors which produce highly-atomized, and hence rapidly vaporizing sprays. A substantial fuel spray characterization effort was conducted to allow selection of nozzles which assured that such sprays were achieved for all fuels. The fuels were specified to cover the following wide ranges of chemical properties: hydrogen, 9.1 to 15 (wt) pct; total aromatics, 0 to 100 (vol) pct; and naphthalene, 0 to 30 (vol) pct. standard fuels (e.g., Jet A, JP4), speciality products (e.g., decalin, xylene tower bottoms) and special fuel blends were included. The latter group included six, 4-component blends prepared to achieve parametric variations in fuel hydrogen, total aromatics and naphthalene contents. The principle influences of fuel chemical properties on the combustor behavior were reflected by the radiation, liner temperature, and exhaust smoke number (or equivalently, soot number density) data. Test results indicated that naphthalene content strongly influenced the radiative heat load while parametric variations in total aromatics did not.

Rosfjord, T. J.

1984-01-01

2

COMBUSTION PROPERTIES AND CALCULATION HIGHER HEATING VALUES OF DIESEL FUELS  

Microsoft Academic Search

Physical, chemical, and fuel properties of diesel fuel samples were investigated in the research. Combustion heats as higher heating values (HHV) of the samples were determined experimentally and calculated from ultimate analysis data. The HHV (MJ kg) of the samples as a function of carbon (C, wt%) and hydrogen (H, wt%) was calculated from the following equation :for which the

Ayhan Demirba?

1998-01-01

3

Combustion Properties of Biologically Sourced Alternative Fuels  

NASA Astrophysics Data System (ADS)

The effects of pressure on various properties of ten different syngas fueled flames were analyzed using one and two dimensional simulations. One-dimensional premixed flames were modeled in CANTERA. Flame speed, adiabatic flame temperature and thermal diffusivity as functions of equivalence ratio and pressure were quantified for the fuels using four chemical kinetic mechanisms. Data from the different mechanisms displayed good agreement with data from previous experimental benchmarks. Two-dimensional axisymmetric co-flow flames were simulated in a state of the art computational framework for modeling laminar flames. Flame structure comparisons were made with past experimental and numerical results as well as with theoretical predictions. Good agreement in stoichiometric flame height was observed with past theoretical and numerical flame height measurements. Visible flame heights had little correlation with the stoichiometric flame heights. The flame radius was also noted to be proportional to p -0.35 at high pressures instead of p-0.5 as predicted by theory.

Barnwal, Abhishek

4

Fuel property effects on engine combustion processes. Final report  

SciTech Connect

A major obstacle to improving spark ignition engine efficiency is the limitations on compression ratio imposed by tendency of hydrocarbon fuels to knock (autoignite). A research program investigated the knock problem in spark ignition engines. Objective was to understand low and intermediate temperature chemistry of combustion processes relevant to autoignition and knock and to determine fuel property effects. Experiments were conducted in an optically and physically accessible research engine, static reactor, and an atmospheric pressure flow reactor (APFR). Chemical kinetic models were developed for prediction of species evolution and autoignition behavior. The work provided insight into low and intermediate temperature chemistry prior to autoignition of n-butane, iso-butane, n-pentane, 1-pentene, n-heptane, iso-octane and some binary blends. Study of effects of ethers (MTBE, ETBE, TAME and DIPE ) and alcohols (methanol and ethanol) on the oxidation and autoignition of primary reference fuel (PRF) blends.

Cernansky, N.P.; Miller, D.L.

1995-04-27

5

Effects of Fuel Physical Properties on Diesel Engine Combustion Using Diesel and Bio-Diesel Fuels  

SciTech Connect

A computational study is performed to investigate the effects of physical property on diesel engine combustion characteristics using bio-diesel fuels. Properties of typical bio-diesel fuels that were either calculated or measured are used in the study and the simulation results are compared with those of conventional diesel fuels. Sensitivity of the computational results to individual physical properties is also investigated, and the results can provide information for desirable characteristics of the blended fuels. The properties considered in this study include liquid density, vapor pressure, surface tension, liquid viscosity, liquid thermal conductivity, liquid specific heat, latent heat, vapor specific heat, vapor diffusion coefficient, vapor viscosity and vapor thermal conductivity. The results show significant effects of the fuel physical properties on ignition delay and burning rates at various engine operating conditions. It is seen that there is no single physical property that dominates differences of ignition delay between diesel and bio-diesel fuels. However, among the 11 properties considered in the study, the simulation results were found to be most sensitive to the liquid fuel density, vapor pressure and surface tension through their effects on the mixture preparation processes.

Ra, Youngchul [ORNL; Reitz, Rolf [University of Wisconsin; McFarlane, Joanna [ORNL; Daw, C Stuart [ORNL

2007-01-01

6

Combustion Gas Properties I-ASTM Jet a Fuel and Dry Air  

NASA Technical Reports Server (NTRS)

A series of computations was made to produce the equilibrium temperature and gas composition for ASTM jet A fuel and dry air. The computed tables and figures provide combustion gas property data for pressures from 0.5 to 50 atmospheres and equivalence ratios from 0 to 2.0.

Jones, R. E.; Trout, A. M.; Wear, J. D.; Mcbride, B. J.

1984-01-01

7

An Analysis of the Impact of Selected Fuel Thermochemical Properties on Internal Combustion Engine Efficiency  

SciTech Connect

In this study we model the effects of 23 different fuels on First and Second Law thermodynamic efficiency of an adiabatic internal combustion engine. First Law efficiency is calculated using lower heating value (LHV) while Second Law efficiency is calculated with exergy, which represents the inherent chemical energy available to produce propulsion. We find that First Law efficiency can deviate by as much as nine percentage points between fuels while Second Law efficiency exhibits a much smaller degree of variability. We also find that First and Second Law efficiency can be nearly the same for some fuels (methane and ethane) but differ substantially for other fuels (hydrogen and ethanol). The differences in First and Second Law efficiency are due to differences in LHV and exergy for a given fuel. In order to explain First Law efficiency differences between fuels as well as the differences between LHV and exergy, we introduce a new term: the molar expansion ratio (MER), defined as the ratio of product moles to reactant moles for complete stoichiometric combustion. We find that the MER is a useful expression for providing a physical explanation for fuel-specific efficiency differences as well as differences between First and Second Law efficiency. First and Second Law efficiency are affected by a number of other fuel-specific thermochemical properties, such as the ratio of specific heat and dissociation of combustion products.

Szybist, James P [ORNL; Chakravathy, Kalyana [Oak Ridge National Laboratory (ORNL); Daw, C Stuart [ORNL

2012-01-01

8

Combustion engineering issues for solid fuel systems  

SciTech Connect

The book combines modeling, policy/regulation and fuel properties with cutting edge breakthroughs in solid fuel combustion for electricity generation and industrial applications. This book provides real-life experiences and tips for addressing the various technical, operational and regulatory issues that are associated with the use of fuels. Contents are: Introduction; Coal Characteristics; Characteristics of Alternative Fuels; Characteristics and Behavior of Inorganic Constituents; Fuel Blending for Combustion Management; Fuel Preparation; Conventional Firing Systems; Fluidized-Bed Firing Systems; Post-Combustion Emissions Control; Some Computer Applications for Combustion Engineering with Solid Fuels; Gasification; Policy Considerations for Combustion Engineering.

Bruce Miller; David Tillman [Pennsylvania State University, University Park, PA (United States). Energy Institute

2008-05-15

9

Properties of air and combustion products of fuels with air  

NASA Technical Reports Server (NTRS)

Thermodynamic and transport properties include ratio of specific heats, molecular weight, viscosity, heat capacity, thermal conductivity, and Prandtl number. Properties are calculated from 300 to 2500 degrees K and for pressures of three and ten atmospheres.

Lewandowski, K.; Poferl, D. J.; Svevla, R.

1969-01-01

10

An Analysis of the Impact of Selected Fuel Thermochemical Properties on Internal Combustion Engine Efficiency  

Microsoft Academic Search

In this study we model the effects of 23 different fuels on First and Second Law thermodynamic efficiency of an adiabatic internal combustion engine. First Law efficiency is calculated using lower heating value (LHV) while Second Law efficiency is calculated with exergy, which represents the inherent chemical energy available to produce propulsion. We find that First Law efficiency can deviate

James P Szybist; Kalyana Chakravathy; C Stuart Daw

2012-01-01

11

Fuel-rich catalytic combustion of a high density fuel  

NASA Technical Reports Server (NTRS)

Fuel-rich catalytic combustion (ER is greater than 4) of the high density fuel exo-tetrahydrocyclopentadiene (JP-10) was studied over the equivalence ratio range 5.0 to 7.6, which yielded combustion temperatures of 1220 to 1120 K. The process produced soot-free gaseous products similar to those obtained with iso-octane and jet-A in previous studies. The measured combustion temperature agreed well with that calculated assuming soot was not a combustion product. The process raised the effective hydrogen/carbon (H/C) ratio from 1.6 to over 2.0, thus significantly improving the combustion properties of the fuel. At an equivalence ratio near 5.0, about 80 percent of the initial fuel carbon was in light gaseous products and about 20 percent in larger condensable molecules. Fuel-rich catalytic combustion has now been studied for three fuels with H/C ratios of 2.25 (iso-octane), 1.92 (jet-A), and 1.6 (JP-10). A comparison of the product distribution of these fuels shows that, in general, the measured concentrations of the combustion products were monotonic functions of the H/C ratio with the exception of hydrogen and ethylene. In these cases, data for JP-10 fell between iso-octane and jet-A rather than beyond jet-A. It is suggested that the ring cross-linking structure of JP-10 may be responsible for this behavior. All the fuels studied showed that the largest amounts of small hydrocarbon molecules and the smallest amounts of large condensable molecules occurred at the lower equivalence ratios. This corresponds to the highest combustion temperatures used in these studies. Although higher temperatures may improve this mix, the temperature is limited. First, the life of the present catalyst would be greatly shortened when operated at temperatures of 1300 K or greater. Second, fuel-rich catalytic combustion does not produce soot because the combustion temperatures used in the experiments were well below the threshold temperature (1350 K) for the formation of soot. Increasing the temperature above this value would remove the soot-free nature of the process. Since all the fuels studied show a similar breakdown of the primary fuel into smaller molecular combustion products, this technique can be applied to all hydrocarbon fuels.

Brabbs, Theodore A.; Merritt, Sylvia A.

1993-01-01

12

Fuel and Combustion Characteristics of Organic Wastes  

NASA Astrophysics Data System (ADS)

From a viewpoint of environmental preservation and resource protection, the recycling of wastes has been promoting. Expectations to new energy resource are growing by decrease of fossil fuel. Biomass is one of new energies for prevent global warning. This study is an attempt to burn biomass lamps made from residues in order to thermally recycle waste products of drink industries. The pyrolytic properties of shochu dregs and used tea leaves were observed by thermo-gravimertic analysis (TG) to obtained fundamental data of drink waste pyrolysis. It observed that shochu dregs pyrolyze under lower temperature than used tea leaves. These wastes were compressed by hot press apparatus in the temperature range from 140 to 180 ░C for use as Bio-fuel (BF). The combustion behavior of BF was observed in fall-type electric furnace, where video-recording was carried out at sequential steps, such as ignition, visible envelope flame combustion and char combustion to obtain combustion characteristics such as ignition delay, visible flame combustion time and char combustion time.

Namba, Kunihiko; Ida, Tamio

13

Method of combustion for dual fuel engine  

DOEpatents

Apparatus and a method of introducing a primary fuel, which may be a coal water slurry, and a high combustion auxiliary fuel, which may be a conventional diesel oil, into an internal combustion diesel engine comprises detecting the load conditions of the engine, determining the amount of time prior to the top dead center position of the piston to inject the main fuel into the combustion chamber, and determining the relationship of the timing of the injection of the auxiliary fuel into the combustion chamber to achieve a predetermined specific fuel consumption, a predetermined combustion efficiency, and a predetermined peak cylinder firing pressure. 19 figures.

Hsu, B.D.; Confer, G.L.; Zujing Shen; Hapeman, M.J.; Flynn, P.L.

1993-12-21

14

Method of combustion for dual fuel engine  

DOEpatents

Apparatus and a method of introducing a primary fuel, which may be a coal water slutty, and a high combustion auxiliary fuel, which may be a conventional diesel oil, into an internal combustion diesel engine comprises detecting the load conditions of the engine, determining the amount of time prior to the top dead center position of the piston to inject the main fuel into the combustion chamber, and determining the relationship of the timing of the injection of the auxiliary fuel into the combustion chamber to achieve a predetermined specific fuel consumption, a predetermined combustion efficiency, and a predetermined peak cylinder firing pressure.

Hsu, Bertrand D. (Erie, PA); Confer, Gregory L. (Erie, PA); Shen, Zujing (Erie, PA); Hapeman, Martin J. (Edinboro, PA); Flynn, Paul L. (Fairview, PA)

1993-12-21

15

Fuel for internal combustion engines  

SciTech Connect

A fuel for internal combustion engines is composed of a mixture of alcohol and gasoline in which the alcohol content is 70 to 85 volume % and the gasoline consists essentially of aromatic, alkanic and cycloalkanic hydrocarbons and, optionally, olefinic hydrocarbons the hydrocarbons having 3-11 carbon atoms, the aromatic hydrocarbons constituting 35 to 45 weight % of the gasoline and the aromatic and any olefinic hydrocarbons constituting cumulatively 35 to 60 weight % of the gasoline.

Ema, S.; Ogasawara, N.; Tsuzuki, K.

1981-07-21

16

Update for combustion properties of wood components  

Microsoft Academic Search

The combustion properties of various biomass and wood materials from various references and from our laboratory were reanalysed. The net heat of combustion for cellulosic materials was found to be 13.23 kJ\\/g times the ratio of stoichiometric oxygen mass to fuel mass, ro, regardless of the material composition. Bomb calorimeter data for original, charred and volatilized material components provide gross

Mark Dietenberger

2002-01-01

17

The effect of fuel and sorbent properties on their partitioning between the flyash and bottom ash streams in fluidized bed combustion  

NASA Astrophysics Data System (ADS)

The fluidized bed combustion process has been employed successfully in several applications, among which steam raising is notable. The use of circulating fluidized bed (CFB) combustion for steam and power generation offers a competitive alternative both in the United States and worldwide, yet there remain technical issues, which if addressed, can improve the competitive position of CFB boiler technology, and improve the operating economics of existing plants. Prominent among these technical issues are the performance of limestones and dolostones as sorbents for emissions control, and the ability of a plant's ash handling system to respond to changes in the fuel or sorbent used by the plant. Study of the effects of fuel and sorbent properties on the partitioning of their resultant bed particles between the ash streams, during the fluidized bed combustion process, has been carried out. This work used results from sorbent tests in a commercial CFB boiler and experimentation with laboratory fluid bed reactors. Sorbents varying in petrographic properties were used in the boiler tests as well as the laboratory testing. Fuels tested had varying distributions of ash content by specific gravity, and ranged in composite ash content from 25 to 49 wt%. Sorbent petrographic properties, described by a characteristic crystallite size, influenced the partitioning of calcium to the flyash and bottom ash streams of the boiler. Under the boiler conditions used for the sorbent tests, sorbent petrographic properties significantly influenced the sorbent consumption rate required by the boiler to maintain air quality compliance. Testing of a range of fuels was carried out in a laboratory fluid bed combustor. Ashing of different specific gravity fractions of the coarse fuel particles revealed a trend where higher specific gravity fractions of the fuel yielded coarse ash particles. A trend was found between increased presence of high ash content particles in a fuel, and increased production of bottom ash by the combustor. The results suggested that the distribution of ash content across the range of fuel particles, sorbent attrition properties, and the size classification characteristics of the system will influence the ash split produced by a fluid bed combustion system. (Abstract shortened by UMI.)

Rozelle, Peter Lawrence

2000-10-01

18

Combustion characterization of beneficiated coal-based fuels  

SciTech Connect

The objectives of this project include: (1) the development of an engineering data base which will provide detailed information on the properties of BCFs influencing combustion, ash deposition, ash erosion, particulate collection, and missions; and (2) the application of this technical data base to predict the performance and economic impacts of firing the BCFs in various commercial boiler designs. The technical approach used to develop the technical data includes: bench-scale fuel property, combustion, and ash deposition tests; pilot-scale combustion and ash effects test; and full-scale combustion tests.

Chow, O.K.; Nsakala, N.Y.

1990-06-01

19

Gas turbine alternative fuels combustion characteristics  

NASA Astrophysics Data System (ADS)

An experimental investigation was conducted to obtain combustion performance and exhaust pollutant concentrations for specific synthetic hydrocarbon fuels. Baseline comparison fuels used were gasoline and diesel fuel number two. Testing was done over a range of fuel to air mass ratios, total mass flow rates, and input combustion air temperatures in a flame-tube-type gas turbine combustor. Test results were obtained in terms of released heat and combustion gas emission values. The results were comparable to those obtained with the base fuels with variations being obtained with changing operating conditions. The release of carbon particles during the tests was minimal.

Rollbuhler, R. James

1989-02-01

20

Combustion and fuel characterization of coal-water fuels  

SciTech Connect

This five-year research project was established to provide sufficient data on coal-water fuel (CWF) chemical, physical, and combustion properties to assess the potential for commercial firing in furnaces designed for gas or oil firing. Extensive laboratory testing was performed at bench-scale, pilot-scale (4 {times} 10{sup 6}Btu/hr) and commercial-scale (25 {times} 10{sup 6} to 50 {times} 10{sup 6}Btu/hr) on a cross-section of CWFs. Fuel performance characteristics were assessed with respect to coal properties, level of coal beneficiation, and slurry formulation. The performance of four generic burner designs was also assessed. Boiler performance design models were applied to analyze the impacts associated with conversion of seven different generic unit designs to CWF firing. Equipment modifications, operating limitations, and retrofit costs were determined for each design when utilizing several CWFs. This report summarizes studies conducted under Task 4. The objective was to quantify CWF atomization and combustion properties utilizing industrial/utility scale equipment. Burners were evaluated and combustion performance differences identified for various CWF formulations. 12 refs., 23 figs., 6 tabs.

Lachowicz, Y.V.; LaFlesh, R.C.

1987-07-01

21

The Effect of Fuel Types on Porous Alumina Produced via Soft Combustion Reaction for Implant Applications  

Microsoft Academic Search

This article describes the effects of fuel types on the porous structure of alumina produced using a soft combustion reaction. There are several combustion parameters that could affect the porous structure of the alumina produced such as fuel-to-oxidizer ratios, ignition temperature, and type of fuels. In this study, the effect of fuel types on alumina properties was studied. Citric acid,

Radin Shafinaz Jamil; Khairunisak Abdul Razak; Nurfateen Fakhariah Ahmad; Hasmaliza Mohamad

2011-01-01

22

Experimental study of gas turbine combustion with elevated fuel temperatures  

NASA Astrophysics Data System (ADS)

Many thermal management challenges have developed as advancements in gas turbine engine designs are made. As the thermal demands on gas turbine engines continue to increase, the heat sink available in the combustor fuel flow becomes more attractive. Increasing the temperature of fuel by using it as a heat sink can lead to higher combustion efficiency due to the increase in flow enthalpy and improved vaporization of the heated fuel. Emissions levels can also be affected by using heated fuels with the levels of carbon monoxide and unburned hydrocarbons tending to decrease while the amount of the oxides of nitrogen tends to increase. Although there are several benefits associated with using heated fuels in gas turbine engines, some problems can arise from their use including combustion instabilities, flashing within the fuel injector, and fuel coking or deposit formation within the fuel system. Various deoxygenation methods have been created to address the coking problem seen when using heated fuels. In the Gas Turbine Test Cell of the High Pressure Laboratory at Purdue University's Maurice J. Zucrow Laboratories, a 5 MW combustion rig was developed to complete combustion test with heated fuels. The facility's supply systems including heated air, jet fuel, cooling water, and nitrogen were designed and integrated to produce simulated engine conditions within the combustion rig. Heating capabilities produced fuel temperatures ranging up to 600 deg F. Testing was completed with two fuel deoxygenation methods: nitrogen sparging and catalytic deoxygenation. Results from the testing campaign included conventional pressure, temperature, and fuel property measurements; however, the most important measurements were the emissions samples that were analyzed for each test condition. Levels of carbon monoxide, unburned hydrocarbons, and oxides of nitrogen were determined as well as the combustion efficiency calculated from these emissions measurements. The trends in emissions and performance from the increase in fuel temperature will be discussed. In addition, high frequency pressure data were recorded during testing to monitor combustion instabilities. Fuel samples were also taken and analyzed to document the changes in the volatile composition of the fuel from the two deoxygenation methods. The testing campaign was extremely successful. All project objectives were met with the heated fuel testing campaign. The combustion rig was run safely with fuel temperature up to 600 deg F, allowing the effects of elevated fuel temperatures on the performance and emissions of a gas turbine combustor to be evaluated as planned.

Wiest, Heather K.

23

30 CFR 77.1105 - Internal combustion engines; fueling.  

Code of Federal Regulations, 2014 CFR

...2014-07-01 2014-07-01 false Internal combustion engines; fueling. 77.1105 Section... Fire Protection ž 77.1105 Internal combustion engines; fueling. Internal combustion engines, except diesels, shall be shut...

2014-07-01

24

30 CFR 56.4103 - Fueling internal combustion engines.  

Code of Federal Regulations, 2011 CFR

...2011-07-01 2011-07-01 false Fueling internal combustion engines. 56.4103 Section 56.4103 ...housekeeping ž 56.4103 Fueling internal combustion engines. Internal combustion engines shall be switched off before...

2011-07-01

25

30 CFR 57.4103 - Fueling internal combustion engines.  

Code of Federal Regulations, 2010 CFR

...2010-07-01 2010-07-01 false Fueling internal combustion engines. 57.4103 Section 57.4103 ...housekeeping ž 57.4103 Fueling internal combustion engines. Internal combustion engines shall be switched off before...

2010-07-01

26

30 CFR 56.4103 - Fueling internal combustion engines.  

Code of Federal Regulations, 2013 CFR

...2013-07-01 2013-07-01 false Fueling internal combustion engines. 56.4103 Section 56.4103 ...housekeeping ž 56.4103 Fueling internal combustion engines. Internal combustion engines shall be switched off before...

2013-07-01

27

30 CFR 56.4103 - Fueling internal combustion engines.  

Code of Federal Regulations, 2014 CFR

...2014-07-01 2014-07-01 false Fueling internal combustion engines. 56.4103 Section 56.4103 ...housekeeping ž 56.4103 Fueling internal combustion engines. Internal combustion engines shall be switched off before...

2014-07-01

28

30 CFR 57.4103 - Fueling internal combustion engines.  

Code of Federal Regulations, 2014 CFR

...2014-07-01 2014-07-01 false Fueling internal combustion engines. 57.4103 Section 57.4103 ...housekeeping ž 57.4103 Fueling internal combustion engines. Internal combustion engines shall be switched off before...

2014-07-01

29

30 CFR 56.4103 - Fueling internal combustion engines.  

Code of Federal Regulations, 2010 CFR

...2010-07-01 2010-07-01 false Fueling internal combustion engines. 56.4103 Section 56.4103 ...housekeeping ž 56.4103 Fueling internal combustion engines. Internal combustion engines shall be switched off before...

2010-07-01

30

30 CFR 57.4103 - Fueling internal combustion engines.  

Code of Federal Regulations, 2013 CFR

...2013-07-01 2013-07-01 false Fueling internal combustion engines. 57.4103 Section 57.4103 ...housekeeping ž 57.4103 Fueling internal combustion engines. Internal combustion engines shall be switched off before...

2013-07-01

31

30 CFR 57.4103 - Fueling internal combustion engines.  

Code of Federal Regulations, 2011 CFR

...2011-07-01 2011-07-01 false Fueling internal combustion engines. 57.4103 Section 57.4103 ...housekeeping ž 57.4103 Fueling internal combustion engines. Internal combustion engines shall be switched off before...

2011-07-01

32

30 CFR 56.4103 - Fueling internal combustion engines.  

Code of Federal Regulations, 2012 CFR

...2012-07-01 2012-07-01 false Fueling internal combustion engines. 56.4103 Section 56.4103 ...housekeeping ž 56.4103 Fueling internal combustion engines. Internal combustion engines shall be switched off before...

2012-07-01

33

30 CFR 77.1105 - Internal combustion engines; fueling.  

Code of Federal Regulations, 2011 CFR

...2011-07-01 2011-07-01 false Internal combustion engines; fueling. 77.1105 Section... Fire Protection ž 77.1105 Internal combustion engines; fueling. Internal combustion engines, except diesels, shall be shut...

2011-07-01

34

30 CFR 77.1105 - Internal combustion engines; fueling.  

Code of Federal Regulations, 2010 CFR

...2010-07-01 2010-07-01 false Internal combustion engines; fueling. 77.1105 Section... Fire Protection ž 77.1105 Internal combustion engines; fueling. Internal combustion engines, except diesels, shall be shut...

2010-07-01

35

30 CFR 57.4103 - Fueling internal combustion engines.  

Code of Federal Regulations, 2012 CFR

...2012-07-01 2012-07-01 false Fueling internal combustion engines. 57.4103 Section 57.4103 ...housekeeping ž 57.4103 Fueling internal combustion engines. Internal combustion engines shall be switched off before...

2012-07-01

36

30 CFR 77.1105 - Internal combustion engines; fueling.  

Code of Federal Regulations, 2012 CFR

...2012-07-01 2012-07-01 false Internal combustion engines; fueling. 77.1105 Section... Fire Protection ž 77.1105 Internal combustion engines; fueling. Internal combustion engines, except diesels, shall be shut...

2012-07-01

37

30 CFR 77.1105 - Internal combustion engines; fueling.  

Code of Federal Regulations, 2013 CFR

...2013-07-01 2013-07-01 false Internal combustion engines; fueling. 77.1105 Section... Fire Protection ž 77.1105 Internal combustion engines; fueling. Internal combustion engines, except diesels, shall be shut...

2013-07-01

38

Fluidized bed combustion of alternative solid fuels  

Microsoft Academic Search

The fluidized bed combustion of a number of alternative fuels of practical interest has been analyzed by a combination of experimental and modeling techniques. Solid fuels of widely different origin (biomass, agricultural, civil and industrial wastes) have been considered in this work. A lab-scale experimental campaign was carried out to evaluate the comminution (fragmentation, attrition) behavior of the fuels. Experimental

Fabrizio Scala; Riccardo Chirone

2004-01-01

39

Combustion and fuel characterization of coal-water fuels  

SciTech Connect

Pittsburgh Energy Technology Center (PETC) of the Department of Energy initiated a comprehensive effort in 1982 to develop the necessary performance and cost data and to assess the commercial viability of coal-water fuels (CWFs) as applied to representative utility and industrial units. The effort comprised six tasks beginning with coal resource evaluation and culminating in the assessment of the technical and economic consequences of switching representative commercial units from oil to state-of-the-art CWF firing. Extensive bench, pilot and commercial-scale tests were performed to develop necessary CWF combustion and fireside performance data for the subsequent boiler performance analyses and retrofit cost estimates. Discussions on transport, rheology, combustion properties, and ash characterization are included. 11 refs., 9 figs., 7 tabs.

Chow, O.K.; Patel, R.L.; Levasseur, A.A.

1987-07-01

40

Combustion Systems for Biomass Fuel  

Microsoft Academic Search

Biomass is one of humanity's earliest sources of energy. Traditionally, biomass has been utilized through direct combustion, and this process is still widely used in many parts of the world. Biomass thermo-chemical conversion investigations are certainly not the most important options at present; combustion is responsible for over 97% of the world's bio-energy production. Biomass combustion is a series of

Ayhan Demirbas

2007-01-01

41

Fuel Interchangeability Considerations for Gas Turbine Combustion  

SciTech Connect

In recent years domestic natural gas has experienced a considerable growth in demand particularly in the power generation industry. However, the desire for energy security, lower fuel costs and a reduction in carbon emissions has produced an increase in demand for alternative fuel sources. Current strategies for reducing the environmental impact of natural gas combustion in gas turbine engines used for power generation experience such hurdles as flashback, lean blow-off and combustion dynamics. These issues will continue as turbines are presented with coal syngas, gasified coal, biomass, LNG and high hydrogen content fuels. As it may be impractical to physically test a given turbine on all of the possible fuel blends it may experience over its life cycle, the need to predict fuel interchangeability becomes imperative. This study considers a number of historical parameters typically used to determine fuel interchangeability. Also addressed is the need for improved reaction mechanisms capable of accurately modeling the combustion of natural gas alternatives.

Ferguson, D.H.

2007-10-01

42

The hydrogen-fueled internal combustion engine: a technical review  

Microsoft Academic Search

A review is given of contemporary research on the hydrogen-fueled internal combustion engine. The emphasis is on light- to medium-duty engine research. We first describe hydrogen-engine fundamentals by examining the engine-specific properties of hydrogen and surveying the existing literature. Here it will be shown that, due to low volumetric efficiencies and frequent preignition combustion events, the power densities of premixed

C. M. White; R. R. Steeper; A. E. Lutz

2006-01-01

43

Characteristics and combustion of future hydrocarbon fuels. [aircraft fuels  

NASA Technical Reports Server (NTRS)

As the world supply of petroleum crude oil is being depleted, the supply of high-quality crude oil is also dwindling. This dwindling supply is beginning to manifest itself in the form of crude oils containing higher percentages of aromatic compounds, sulphur, nitrogen, and trace constituents. The result of this trend is described and the change in important crude oil characteristics, as related to aircraft fuels, is discussed. As available petroleum is further depleted, the use of synthetic crude oils (those derived from coal and oil shale) may be required. The principal properties of these syncrudes and the fuels that can be derived from them are described. In addition to the changes in the supply of crude oil, increasing competition for middle-distillate fuels may require that specifications be broadened in future fuels. The impact that the resultant potential changes in fuel properties may have on combustion and thermal stability characteristics is illustrated and discussed in terms of ignition, soot formation, carbon deposition flame radiation, and emissions.

Rudey, R. A.; Grobman, J. S.

1978-01-01

44

Combustion characterization of beneficiated coal-based fuels  

SciTech Connect

The Pittsburgh Energy Technology Center of the US Department of Energy has contracted with Combustion Engineering, Inc. (CE) to perform a three-year project on Combustion Characterization of Beneficiated Coal-Based Fuels.'' The beneficiated coals are produced by other contractors under the DOE Coal Preparation Program. Several contractor-developed advanced coal cleaning processes are being run at the cleaning facility in Homer City, Pennsylvania, to produce 20-ton batches of fuels for shipment to CE's laboratory in Windsor, Connecticut. CE then processes the products into either a coal-water fuel (CVVT) or a dry microfine pulverized coal (DMPC) form for combustion testing. The objectives of this project include: (1) the development of an engineering data base which will provide detailed information on the properties of BCFs influencing combustion, ash deposition, ash erosion, particulate collection, and emissions; and (2) the application of this technical data base to predict the performance and economic impacts of firing the BCFs in various commercial boiler designs. The technical approach used to develop the technical data includes: bench-scale fuel property, combustion, and ash deposition tests; pilot-scale combustion and ash effects tests; and full-scale combustion tests. Subcontractors to CE to perform parts of the test work are the Massachusetts Institute of Technology (MIT), Physical Science, Inc. Technology Company (PSIT) and the University of North Dakota Energy and Environmental Research Center (UNDEERC). Twenty fuels will be characterized during the three-year base program: three feed coals, fifteen BCFS, and two conventionally cleaned coals for full-scale tests. Approximately, nine BCFs will be in dry microfine coal (DMPC) form, and six BCFs will be in coal-water fuel (CWF) form. Additional BCFs would be characterized during optional project supplements.

Chow, O.K.; Nsakala, N.Y.

1990-11-01

45

Combustion of biomass and low CV fuels  

Microsoft Academic Search

This paper reviews the progress made in several areas concerning the combustion of biomass and low calorific value fuels at Cardiff over the last 20 years, including:Ľ Efficient utilisation of low calorific value gases.Ľ The use of cyclone combustors with poor quality solid fuels.Ľ Pyrolysis processes and wastes.Ľ Small efficient, well controlled, batch fed biomass stoves.Conclusions are drawn as to

T. ODoherty

2000-01-01

46

Fuel injector for an internal combustion engine  

Microsoft Academic Search

A fuel injector is described for an internal combustion engine, which comprises: a body having an axial bore; a normally closed injection nozzle mounted to the body in alignment with the bore, the injection nozzle being of the differential pressure type including a pressure chamber and a needle valve; injection fuel supply means in the body for supplying a high

T. Yoshinaga; T. Igashira; Y. Sakakibara; Y. Natsuyama

1986-01-01

47

Combustion characteristics of gas turbine alternative fuels  

NASA Technical Reports Server (NTRS)

An experimental investigation was conducted to obtain combustion performance values for specific heavyend, synthetic hydrocarbon fuels. A flame tube combustor modified to duplicate an advanced gas turbine engine combustor was used for the tests. Each fuel was tested at steady-state operating conditions over a range of mass flow rates, fuel-to-air mass ratio, and inlet air temperatures. The combustion pressure, as well as the hardware, were kept nearly constant over the program test phase. Test results were obtained in regards to geometric temperature pattern factors as a function of combustor wall temperatures, the combustion gas temperature, and the combustion emissions, both as affected by the mass flow rate and fuel-to-air ratio. The synthetic fuels were reacted in the combustor such that for most tests their performance was as good, if not better, than the baseline gasoline or diesel fuel tests. The only detrimental effects were that at high inlet air temperature conditions, fuel decomposition occurred in the fuel atomizing nozzle passages resulting in blockage. And the nitrogen oxide emissions were above EPA limits at low flow rate and high operating temperature conditions.

Rollbuhler, R. James

1987-01-01

48

A comprehensive combustion model for biodiesel-fueled engine simulations  

NASA Astrophysics Data System (ADS)

Engine models for alternative fuels are available, but few are comprehensive, well-validated models that include accurate physical property data as well as a detailed description of the fuel chemistry. In this work, a comprehensive biodiesel combustion model was created for use in multi-dimensional engine simulations, specifically the KIVA3v R2 code. The model incorporates realistic physical properties in a vaporization model developed for multi-component fuel sprays and applies an improved mechanism for biodiesel combustion chemistry. A reduced mechanism was generated from the methyl decanoate (MD) and methyl-9-decenoate (MD9D) mechanism developed at Lawrence Livermore National Laboratory. It was combined with a multi-component mechanism to include n-heptane in the fuel chemistry. The biodiesel chemistry was represented using a combination of MD, MD9D and n-heptane, which varied for a given fuel source. The reduced mechanism, which contained 63 species, accurately predicted ignition delay times of the detailed mechanism over a range of engine-specific operating conditions. Physical property data for the five methyl ester components of biodiesel were added to the KIVA library. Spray simulations were performed to ensure that the models adequately reproduce liquid penetration observed in biodiesel spray experiments. Fuel composition impacted liquid length as expected, with saturated species vaporizing more and penetrating less. Distillation curves were created to ensure the fuel vaporization process was comparable to available data. Engine validation was performed against a low-speed, high-load, conventional combustion experiments and the model was able to predict the performance and NOx formation seen in the experiment. High-speed, low-load, low-temperature combustion conditions were also modeled, and the emissions (HC, CO, NOx) and fuel consumption were well-predicted for a sweep of injection timings. Finally, comparisons were made between the results of biodiesel composition (palm vs. soy) and fuel blends (neat vs. B20). The model effectively reproduced the trends observed in the experiments.

Brakora, Jessica L.

49

Internal combustion engine fuel rail assembly joint  

SciTech Connect

This patent describes a fuel rail assembly of an internal combustion engine. It comprises a non-metallic fuel rail containing devices that are part of a fuel injection system of the engine, and also comprising a metal tube which is in fluid communication with a fuel passage in the non-metallic fuel rail and connected with the non-metallic fuel rail by means of a joint, characterized in that the joint comprises a cylindrical metal sleeve that is partially embedded in the non-metallic fuel rail such that a first cylindrical portion of the non-metallic fuel rail lines an interior end portion of the sleeve and is in fluid communication with the fuel passage in the non-metallic fuel rail and such that the sleeve lines the interior of a second cylindrical portion of the non-metallic fuel rail, the metal tube and the first cylindrical portion of the non-metallic fuel rail fit together in a sealed manner to place the metal tube in fluid communication with the fuel passage in the non-metallic fuel rail, the sleeve has another portion that is not embedded in the non-metallic fuel rail, and a retention means coacts with the another axis end segment and with the metal tube to retain the metal tube and the first cylindrical portion of the non-metallic fuel rail fit together in a sealed manner.

Imoehl, W.J.

1992-04-21

50

Combustion and fuel characterization of coal-water fuels  

SciTech Connect

This five-year research project was established to provide sufficient data on coal-water fuel (CWF) chemical, physical, and combustion properties to assess the potential for commercial firing in furnaces designed for gas or oil firing. Extensive laboratory testing was performed at bench-scale, pilot-scale (4 {times} 10{sup 6}Btu/hr) and commercial-scale (25 {times} 10{sup 6} to 50 {times} 10{sup 6}Btu/hr) on a cross-section of CWFs. Fuel performance characteristics were assessed with respect to coal properties, level of coal beneficiation, and slurry formulation. The performance of four generic burner designs was also assessed. Boiler performance design models were applied to analyze the impacts associated with conversion of seven different generic unit designs to CWF firing. Equipment modifications, operating limitations, and retrofit costs were determined for each design when utilizing several CWFs. Unit performance analyses showed significantly better load capacity for utility and industrial boilers as the CWF feed coal ash content is reduced to 5% or 2.6%. In general, utility units had more attractive capacity limits and retrofit costs than the industrial boilers and process heaters studied. Economic analyses indicated that conversion to CWF firing generally becomes feasible when differential fuel costs are above $1.00/10{sup 6}Btu. 60 figs., 24 tabs.

Chow, O.K.; Gralton, G.W.; Lachowicz, Y.V.; Laflesh, R.C.; Levasseur, A.A.; Liljedahl, G.N.

1989-02-01

51

Combustion engine for solid and liquid fuels  

NASA Technical Reports Server (NTRS)

A combustion engine having no piston, a single cylinder, and a dual-action, that is applicable for solid and liquid fuels and propellants, and that functions according to the principle of annealing point ignition is presented. The invention uses environmentally benign amounts of fuel and propellants to produce gas and steam pressure, and to use a simple assembly with the lowest possible consumption and constant readiness for mixing and burning. The advantage over conventional combustion engines lies in lower consumption of high quality igniting fluid in the most cost effective manner.

Pabst, W.

1986-01-01

52

Survey of Hydrogen Combustion Properties  

NASA Technical Reports Server (NTRS)

This literature digest of hydrogen-air combustion fundamentals presents data on flame temperature, burning velocity, quenching distance, flammability limits, ignition energy, flame stability, detonation, spontaneous ignition, and explosion limits. The data are assessed, recommended values are given, and relations among various combustion properties are discussed. New material presented includes: theoretical treatment of variation in spontaneous ignition lag with temperature, pressure, and composition, based on reaction kinetics of hydrogen-air composition range for 0.01 to 100 atmospheres and initial temperatures of 0 degrees to 1400 degrees k.

Drell, Isadore L; Belles, Frank E

1958-01-01

53

Catalytic combustion with incompletely vaporized residual fuel  

NASA Technical Reports Server (NTRS)

Catalytic combustion of fuel lean mixtures of incompletely vaporized residual fuel and air was investigated. The 7.6 cm diameter, graded cell reactor was constructed from zirconia spinel substrate and catalyzed with a noble metal catalyst. Streams of luminous particles exited the rector as a result of fuel deposition and carbonization on the substrate. Similar results were obtained with blends of No. 6 and No. 2 oil. Blends of shale residual oil and No. 2 oil resulted in stable operation. In shale oil blends the combustor performance degraded with a reduced degree of fuel vaporization. In tests performed with No. 2 oil a similar effect was observed.

Rosfjord, T. J.

1981-01-01

54

Method for combustion of gaseous fuels and flue gases  

Microsoft Academic Search

The invention discloses a method for combustion of gaseous fuels and flue gases in which the heat content of the combustion products is partially recycled to the combustion process by heat exchange with combustion air and\\/or gas, and air and gas are fed to a reaction chamber, where a surface combustion takes place separating air and gas regions, and the

1979-01-01

55

Effect of different fuels on structural, photo and thermo luminescence properties of solution combustion prepared Y2SiO5 nanopowders  

NASA Astrophysics Data System (ADS)

Y2SiO5 nanopowders are prepared by solution combustion method using DFH, sugar and urea as fuels. The final product was well characterized by powder X-ray diffraction, Scanning Electron Microscopy and UV-Vis spectroscopy. The average crystallite size was estimated using Debye-Scherer's formula and Williamson-Hall plots and are found to be in the range 34-40 nm for DFH, 45-50 nm for urea and 35-42 nm for sugar respectively. X1-X2 type YSO phase was obtained for all the samples calcined from 1200 to 1400 ░C. The optical energy band gaps (Eg) of the samples were estimated from Tauc relation and varies from 5.58 to 5.60 eV. SEM micrographs of sugar and urea used Y2SiO5 show agglomerated particles with porous morphology. However, for the sample prepared using DFH fuel observed to be almost spherical in shape. Thermoluminescence (TL) properties of ?-irradiated (1-5 kGy) and UV irradiated (1-30 min) Y2SiO5 nanopowder at a heating rate of 2.5 ░C s-1 was studied. The samples prepared by using urea and sugar fuels show a broad TL glow peak at 189 ░C. However, DFH used Y2SiO5 show a well resolved peak at 196 ░C with shouldered peak at 189 ░C. Among the fuels, DFH used Y2SiO5 show simple glow peak structure which perhaps useful in radiation dosimetry. This may be due to fuel and particle size effect. The kinetic parameters such as activation energy (E), frequency factor (s) and order of kinetics are estimated by Chens glow peak shape method.

Ramakrishna, G.; Nagabhushana, H.; Sunitha, D. V.; Prashantha, S. C.; Sharma, S. C.; Nagabhushana, B. M.

2014-06-01

56

Effect of different fuels on structural, photo and thermo luminescence properties of solution combustion prepared Y(2)SiO(5) nanopowders.  

PubMed

Y(2)SiO(5) nanopowders are prepared by solution combustion method using DFH, sugar and urea as fuels. The final product was well characterized by powder X-ray diffraction, Scanning Electron Microscopy and UV-Vis spectroscopy. The average crystallite size was estimated using Debye-Scherer's formula and Williamson-Hall plots and are found to be in the range 34-40nm for DFH, 45-50nm for urea and 35-42nm for sugar respectively. X1-X2 type YSO phase was obtained for all the samples calcined from 1200 to 1400░C. The optical energy band gaps (Eg) of the samples were estimated from Tauc relation and varies from 5.58 to 5.60eV. SEM micrographs of sugar and urea used Y(2)SiO(5) show agglomerated particles with porous morphology. However, for the sample prepared using DFH fuel observed to be almost spherical in shape. Thermoluminescence (TL) properties of ?-irradiated (1-5kGy) and UV irradiated (1-30min) Y(2)SiO(5) nanopowder at a heating rate of 2.5░Cs(-1) was studied. The samples prepared by using urea and sugar fuels show a broad TL glow peak at 189░C. However, DFH used Y(2)SiO(5) show a well resolved peak at 196░C with shouldered peak at 189░C. Among the fuels, DFH used Y(2)SiO(5) show simple glow peak structure which perhaps useful in radiation dosimetry. This may be due to fuel and particle size effect. The kinetic parameters such as activation energy (E), frequency factor (s) and order of kinetics are estimated by Chens glow peak shape method. PMID:24632171

Ramakrishna, G; Nagabhushana, H; Sunitha, D V; Prashantha, S C; Sharma, S C; Nagabhushana, B M

2014-06-01

57

Superheated fuel injection for combustion of liquid-solid slurries  

Microsoft Academic Search

A method and device are claimed for obtaining, upon injection, flash evaporation of a liquid in a slurry fuel to aid in ignition and combustion. The device is particularly beneficial for use of coal-water slurry fuels in internal combustion engines such as diesel engines and gas turbines, and in external combustion devices such as boilers and furnaces. The slurry fuel

Robben

1984-01-01

58

Superheated fuel injection for combustion of liquid-solid slurries  

Microsoft Academic Search

A method and device for obtaining, upon injection, flash evaporation of a liquid in a slurry fuel to aid in ignition and combustion. The device is particularly beneficial for use of coal-water slurry fuels in internal combustion engines such as diesel engines and gas turbines, and in external combustion devices such as boilers and furnaces. The slurry fuel is heated

Robben

1985-01-01

59

The Effect of Fuel Types on Porous Alumina Produced via Soft Combustion Reaction for Implant Applications  

Microsoft Academic Search

This article describes the effects of fuel types on the porous structure of alumina produced using a soft combustion reaction.\\u000a There are several combustion parameters that could affect the porous structure of the alumina produced such as fuel-to-oxidizer\\u000a ratios, ignition temperature, and type of fuels. In this study, the effect of fuel types on alumina properties was studied.\\u000a Citric acid,

Radin Shafinaz Jamil; Khairunisak Abdul Razak; Nurfateen Fakhariah Ahmad; Hasmaliza Mohamad

60

FUEL NOX CONTROL BY CATALYTIC COMBUSTION  

EPA Science Inventory

The report gives results of an experimental study to: (1) define operating conditions for catalytic combustors that give low levels of NOx emissions for fuelbound nitrogen compounds, and (2) quantitatively determine the fate of fuel nitrogen during catalytic combustion. Tests wer...

61

CONTROLLING EMISSIONS FROM FUEL AND WASTE COMBUSTION  

EPA Science Inventory

Control of emissions from combustion of fuels and wastes has been a traditional focus of air pollution regulations. Significant technology developments of the '50s and '60s have been refined into reliable chemical and physical process unit operations. In the U.S., acid rain legis...

62

Fuels Performance: Navigating the Intersection of Fuels and Combustion (Brochure)  

SciTech Connect

Researchers at the National Renewable Energy Laboratory (NREL), the only national laboratory dedicated 100% to renewable energy and energy efficiency, recognize that engine and infrastructure compatibility can make or break the impact of even the most promising fuel. NREL and its industry partners navigate the intersection of fuel chemistry, ignition kinetics, combustion, and emissions, with innovative approaches to engines and fuels that meet drivers' expectations, while minimizing petroleum use and GHGs.

Not Available

2014-12-01

63

Fuel Flexible Combustion Systems for High-Efficiency Utilization of Opportunity Fuels in Gas Turbines  

SciTech Connect

The purpose of this program was to develop low-emissions, efficient fuel-flexible combustion technology which enables operation of a given gas turbine on a wider range of opportunity fuels that lie outside of current natural gas-centered fuel specifications. The program encompasses a selection of important, representative fuels of opportunity for gas turbines with widely varying fundamental properties of combustion. The research program covers conceptual and detailed combustor design, fabrication, and testing of retrofitable and/or novel fuel-flexible gas turbine combustor hardware, specifically advanced fuel nozzle technology, at full-scale gas turbine combustor conditions. This project was performed over the period of October 2008 through September 2011 under Cooperative Agreement DE-FC26-08NT05868 for the U.S. Department of Energy/National Energy Technology Laboratory (USDOE/NETL) entitled "Fuel Flexible Combustion Systems for High-Efficiency Utilization of Opportunity Fuels in Gas Turbines". The overall objective of this program was met with great success. GE was able to successfully demonstrate the operability of two fuel-flexible combustion nozzles over a wide range of opportunity fuels at heavy-duty gas turbine conditions while meeting emissions goals. The GE MS6000B ("6B") gas turbine engine was chosen as the target platform for new fuel-flexible premixer development. Comprehensive conceptual design and analysis of new fuel-flexible premixing nozzles were undertaken. Gas turbine cycle models and detailed flow network models of the combustor provide the premixer conditions (temperature, pressure, pressure drops, velocities, and air flow splits) and illustrate the impact of widely varying fuel flow rates on the combustor. Detailed chemical kinetic mechanisms were employed to compare some fundamental combustion characteristics of the target fuels, including flame speeds and lean blow-out behavior. Perfectly premixed combustion experiments were conducted to provide experimental combustion data of our target fuels at gas turbine conditions. Based on an initial assessment of premixer design requirements and challenges, the most promising sub-scale premixer concepts were evaluated both experimentally and computationally. After comprehensive screening tests, two best performing concepts were scaled up for further development. High pressure single nozzle tests were performed with the scaled premixer concepts at target gas turbine conditions with opportunity fuels. Single-digit NOx emissions were demonstrated for syngas fuels. Plasma-assisted pilot technology was demonstrated to enhance ignition capability and provide additional flame stability margin to a standard premixing fuel nozzle. However, the impact of plasma on NOx emissions was observed to be unacceptable given the goals of this program and difficult to avoid.

Venkatesan, Krishna

2011-11-30

64

The hydrogen-fueled internal combustion engine : a technical review.  

SciTech Connect

A review is given of contemporary research on the hydrogen-fueled internal combustion engine. The emphasis is on light- to medium-duty engine research. We first describe hydrogen-engine fundamentals by examining the engine-specific properties of hydrogen and surveying the existing literature. Here it will be shown that, due to low volumetric efficiencies and frequent preignition combustion events, the power densities of premixed or port-fuel-injected hydrogen engines are diminished relative to gasoline-fueled engines. Significant progress has been made in the development of advanced hydrogen engines with improved power densities. We discuss several examples and their salient features. Finally, we consider the overall progress made and provide suggestions for future work.

Steeper, Richard R.; White, Christopher M.; Lutz, Andrew E.

2005-05-01

65

Automotive fuels and internal combustion engines: a chemical perspective.  

PubMed

Commercial transportation fuels are complex mixtures containing hundreds or thousands of chemical components, whose composition has evolved considerably during the past 100 years. In conjunction with concurrent engine advancements, automotive fuel composition has been fine-tuned to balance efficiency and power demands while minimizing emissions. Pollutant emissions from internal combustion engines (ICE), which arise from non-ideal combustion, have been dramatically reduced in the past four decades. Emissions depend both on the engine operating parameters (e.g. engine temperature, speed, load, A/F ratio, and spark timing) and the fuel. These emissions result from complex processes involving interactions between the fuel and engine parameters. Vehicle emissions are comprised of volatile organic compounds (VOCs), CO, nitrogen oxides (NO(x)), and particulate matter (PM). VOCs and NO(x) form photochemical smog in urban atmospheres, and CO and PM may have adverse health impacts. Engine hardware and operating conditions, after-treatment catalysts, and fuel composition all affect the amount and composition of emissions leaving the vehicle tailpipe. While engine and after-treatment effects are generally larger than fuel effects, engine and after-treatment hardware can require specific fuel properties. Consequently, the best prospects for achieving the highest efficiency and lowest emissions lie with optimizing the entire fuel-engine-after-treatment system. This review provides a chemical perspective on the production, combustion, and environmental aspects of automotive fuels. We hope this review will be of interest to workers in the fields of chemical kinetics, fluid dynamics of reacting flows, atmospheric chemistry, automotive catalysts, fuel science, and governmental regulations. PMID:16565750

Wallington, T J; Kaiser, E W; Farrell, J T

2006-04-01

66

Toward the Impact of Fuel Evaporation-Combustion Interaction on Spray Combustion in Gas Turbine Combustion Chambers. Part I: Effect of Partial Fuel Vaporization on Spray Combustion  

Microsoft Academic Search

\\u000a This work aims at investigating the impact of the interaction between evaporation process and combustion on spray combustion\\u000a characteristics in gas turbine combustion chambers. It is subdivided into two parts. The first part studies how the evaporation\\u000a process affects the behavior of partially pre-vaporized spray combustion. The second part attempts to answer the question\\u000a how the fuel evaporation process behaves

Amsini Sadiki; W. Ahmadi; Mouldi Chrigui; J. Janicka

67

Biomass fuel combustion and health*  

PubMed Central

Biomass fuels (wood, agricultural waste, and dung) are used by about half the world's population as a major, often the only, source of domestic energy for cooking and heating. The smoke emissions from these fuels are an important source of indoor air pollution, especially in rural communities in developing countries. These emissions contain important pollutants that adversely affect healthŚsuch as suspended particulate matter and polycyclic organic matter which includes a number of known carcinogens, such as benzo[a]pyrene, as well as gaseous pollutants like carbon monoxide and formaldehyde. Exposure to large amounts of smoke may present a health risk that is of a similar order of magnitude to the risk from tobacco smoke. The effects on health arising from exposure to air pollution are reviewed, based on what has been reported in the literature so far. Further and more detailed information on exposures and on the epidemiological aspects is urgently required. The persons most frequently affected are women who do the cooking for households in rural villages; they suffer from impaired health due to prolonged and repeated contact with these harmful pollutants. When they are pregnant, the developing fetus may also be exposed and this leads to the risk of excess deaths. In the developing countries, exposure to biomass fuel emissions is probably one of the most important occupational health hazards for women. A conservatively estimated 300-400 million people worldwide, mostly in the rural areas of developing countries, are affected by these problems. PMID:3872729

de Koning, H. W.; Smith, K. R.; Last, J. M.

1985-01-01

68

Fuel effects on gas turbine combustion systems  

SciTech Connect

The effects of variations in properties and characteristics of liquid hydrocarbon base fuels in gas turbine engine combustors was investigated. Baseline fuels consisted of military specification materials processed from petroleum and shale oil. Experimental fuels were comprised of liquid petroleum blends that were prepared specifically to exhibit desired physical and chemical properties. These fuels were assessed for their influence on ignition and performance characteristics in combustors of the F100, TF30, and J57 (TF33) engines at simulated operating conditions. In general, during relatively short duration tests, combustor ignition and performance became increasingly poorer as fuel quality deviated from specification or historical values.

Mosier, S.A.

1984-01-01

69

Performance/combustion characteristics of six Canadian alternative fuels tested in a bombardier medium speed diesel  

SciTech Connect

Six experimental fuels representative of Canadian future fuel options were tested against a reference fuel in a bombardier 12 cylinder, 4 stroke, 3000 hp, medium speed diesel. The reference fuel was a straight run ASTM number2-d. Each fuel was analyzed for physical and chemical properties. The engine was tested under a marine application propeller law load curve at 8 different engine speeds. Correlations between fuel properties and engine performance/combustion behaviour indicated that the longest ignition delays were observed for fuels with the lowest cetane numbers. Rates of combustion pressure rise increased proportionately with decreased cetane numbers and increased levels of aromatic components. Increases in peak combustion pressures and rates of pressure rise at low engine speeds are not expected to pose durability problems with medium speed engines operating at or near rated speed and load for the fuels tested.

Grimsey, R.G.; Stoneman, R.T.; Webster, G.D.; Chan, D.Y.

1985-01-01

70

Studies of oscillatory combustion and fuel vaporization  

NASA Technical Reports Server (NTRS)

Research projects involving oscillatory combustion and fuel vaporization are reported. Comparisons of experimental and theoretical droplet vaporization histories under ambient conditions such that the droplet may approach its thermodynamic critical point are presented. Experimental data on instantaneous heat transfer from a gas to a solid surface under conditions of oscillatory pressure with comparisons to an unsteady one-dimensional model are analyzed. Droplet size and velocity distribution in a spray as obtained by use of a double flash fluorescent method were investigated.

Borman, G. L.; Myers, P. S.; Uyehara, O. A.

1972-01-01

71

Numerical modeling of hydrogen-fueled internal combustion engines  

SciTech Connect

The planned use of hydrogen as the energy carrier of the future introduces new challenges and opportunities, especially to the engine design community. Hydrogen is a bio-friendly fuel that can be produced from renewable resources and has no carbon dioxide combustion products; and in a properly designed ICE, almost zero NO{sub x} and hydrocarbon emissions can be achieved. Because of the unique properties of hydrogen combustion - in particular the highly wrinkled nature of the laminar flame front due to the preferential diffusion instability - modeling approaches for hydrocarbon gaseous fuels are not generally applicable to hydrogen combustion. This paper reports on the current progress to develop a engine design capability based on KIVA family of codes for hydrogen-fueled, spark-ignited engines in support of the National Hydrogen Program. A turbulent combustion model, based on a modified eddy-turnover model in conjunction with an intake flow valve model, is found to describe well the efficiency and NO{sub x} emissions of this engine satisfy the Equivalent Zero Emission Vehicle (EZEV) standard established by the California Resource Board. 26 refs., 10 figs., 1 tab.

Johnson, N.L.; Amsden, A.A.

1996-12-31

72

Demonstration of catalytic combustion with residual fuel  

NASA Technical Reports Server (NTRS)

An experimental program was conducted to demonstrate catalytic combustion of a residual fuel oil. Three catalytic reactors, including a baseline configuration and two backup configurations based on baseline test results, were operated on No. 6 fuel oil. All reactors were multielement configurations consisting of ceramic honeycomb catalyzed with palladium on stabilized alumina. Stable operation on residual oil was demonstrated with the baseline configuration at a reactor inlet temperature of about 825 K (1025 F). At low inlet temperature, operation was precluded by apparent plugging of the catalytic reactor with residual oil. Reduced plugging tendency was demonstrated in the backup reactors by increasing the size of the catalyst channels at the reactor inlet, but plugging still occurred at inlet temperature below 725 K (845 F). Operation at the original design inlet temperature of 589 K (600 F) could not be demonstrated. Combustion efficiency above 99.5% was obtained with less than 5% reactor pressure drop. Thermally formed NO sub x levels were very low (less than 0.5 g NO2/kg fuel) but nearly 100% conversion of fuel-bound nitrogen to NO sub x was observed.

Dodds, W. J.; Ekstedt, E. E.

1981-01-01

73

Combustion characterization of beneficiated coal-based fuels  

SciTech Connect

The objectives of this project include: (1) the development of an engineering data base which will provide detailed information on the properties of BCFs influencing combustion, ash deposition, ash erosion, particulate collection, and emissions; and (2) the application of this technical data base to predict the performance and economic impacts of firing the BCFs in various commercial boiler designs. The technical approach used to develop the technical data includes: bench-scale fuel property, conbustion, and ash deposition tests; pilot-scale combustion and ash effects tests; and full-scale combustion tests. Subcontractors to CE to perform parts of the test work are the Massachusetts Institute of Technology (MIT), Physical Sciences, Inc. Technology Company (PSIT) and the University of North Dakota Energy and Environmental Research Center (UNDEERC). Twenty fuels will be characterized during the three-year base program: three feed coals, fifteen BCFs, and two conventionally cleaned coals for the full-scale tests. Approximately nine BCFs will be in dry ultra-fine coal (DUC) form, and six BCFs will be in coal-water fuel (CWF) form. Additional BCFs would be characterized during optional project supplements.

Chow, O.K.; Nsakala, N.Y.

1990-08-01

74

Fuel Property Effects on Emissions from High Efficiency Clean Combustion in a Diesel Engine (SAE Paper Number 2006-01-0080)  

SciTech Connect

High-efficiency clean combustion (HECC) modes provide simultaneous reductions in diesel particulate matter and nitrogen-oxides emissions while retaining efficiencies characteristic of normal diesel engines. Fuel parameters may have significant impacts on the ability to operate in HECC modes and on the emissions produced in HECC modes. In this study, 3 diesel-range fuels and 2 oxygenated blends are burned in both normal and HECC modes at 3 different engine conditions. The results show that fuel effects play an important role in the emissions of hydrocarbons, particulate matter, and carbon monoxide but do not significantly impact NOX emissions in HECC modes. HECC modes are achievable with 5% biodiesel blends in addition to petroleum-based and oil-sands derived fuels. Soot precursor and oxygenated compound concentrations in the exhaust were observed to generally increase with the sooting tendency of the fuel in HECC modes.

Sluder, Scott [ORNL; Wagner, Robert M [ORNL; Lewis Sr, Samuel Arthur [ORNL; Storey, John Morse [ORNL

2006-01-01

75

Introduction Fossil fuel combustion by aviation, shipping and road  

E-print Network

96 Introduction Fossil fuel combustion by aviation, shipping and road traffic contributes about one. here we summarize some of the first findings. Emissions by transport modes Emissions from fossil fuel to global CO emissions are estimated to be much smaller, likely due to more efficient fuel combustion. Road

Haak, Hein

76

Recent advances in the combustion of water fuel emulsion  

Microsoft Academic Search

Recent advances in the combustion of water fuel emulsion which consists of base fuel and water doped with or without a trace content of surfactant are reviewed. The focus is on the fundamental mechanism relevant to the micro-explosion phenomena leading to the secondary atomization which is not common to the combustion of pure fuel. Described at first are the kinetic

T. Kadota; H. Yamasaki

2002-01-01

77

Investigation of Bio-Diesel Fueled Engines under Low-Temperature Combustion Strategies  

SciTech Connect

In accordance with meeting DOE technical targets this research was aimed at developing and optimizing new fuel injection technologies and strategies for the combustion of clean burning renewable fuels in diesel engines. In addition a simultaneous minimum 20% improvement in fuel economy was targeted with the aid of this novel advanced combustion system. Biodiesel and other renewable fuels have unique properties that can be leveraged to reduce emissions and increase engine efficiency. This research is an investigation into the combustion characteristics of biodiesel and its impacts on the performance of a Low Temperature Combustion (LTC) engine, which is a novel engine configuration that incorporates technologies and strategies for simultaneously reducing NOx and particulate emissions while increasing engine efficiency. Generating fundamental knowledge about the properties of biodiesel and blends with petroleum-derived diesel and their impact on in-cylinder fuel atomization and combustion processes was an important initial step to being able to optimize fuel injection strategies as well as introduce new technologies. With the benefit of this knowledge experiments were performed on both optical and metal LTC engines in which combustion and emissions could be observed and measured under realistic conditions. With the aid these experiments and detailed combustion models strategies were identified and applied in order to improve fuel economy and simultaneously reduce emissions.

Chia-fon F. Lee; Alan C. Hansen

2010-09-30

78

Vaporization and combustion of fuel droplets at supercritical conditions  

NASA Technical Reports Server (NTRS)

Vaporization and combustion liquid-fuel droplets in both sub- and super-critical environments have been examined. The formulation is based on the complete conservation equations for both gas and liquid phases, and accommodates finite-rate chemical kinetics and a full treatment of liquid-vapor phase equilibrium at the droplet surface. The governing equations and the associated interface boundary conditions are solved numerically using a fully coupled, implicit scheme with the dual time-stepping integration technique. The model is capable of treating the entire droplet history, including the transition from the subcritical to the supercritical state. As a specific example, the combustion of n-pentane fuel droplets in air is studied for pressures of 5-140 atm. In addition, the dynamic responses of droplet vaporization and combustion to ambient-pressure oscillations are investigated. Results indicate that the droplet gasification and burning mechanisms depend greatly on the ambient pressure. In particular, a rapid enlargement of the vaporization and combustion responses occurs when the droplet surface reaches its critical point, mainly due to the strong variations of latent heat of vaporization and thermophysical properties at the critical state.

Yang, Vigor

1991-01-01

79

Influence of combustion conditions and coal properties on physical properties of fly ash generated from pulverized coal combustion  

SciTech Connect

To develop combustion technology for upgrading the quality of fly ash, the influences of the coal properties, such as the size of pulverized coal particles and the two-stage combustion ratio during the combustion, on the fly ash properties were investigated using our test furnace. The particle size, density, specific surface area (obtained by the Blaine method), and shape of fly ash particles of seven types of coal were measured. It was confirmed that the size of pulverized coal particles affects the size of the ash particles. Regarding the coal properties, the fuel ratio affected the ash particle size distribution. The density and shape of the ash particles strongly depended on their ash size. Our results indicated that the shape of the ash particles and the concentration of unburned carbon affected the specific surface area. The influence of the two-stage combustion ratio was limited. 8 refs., 13 figs., 3 tabs.

Hiromi Shirai; Hirofumi Tsuji; Michitaka Ikeda; Toshinobu Kotsuji [Central Research Institute of Electric Power Industry, Kanagawa (Japan)

2009-07-15

80

Hydrogen-fueled internal combustion engines.  

SciTech Connect

The threat posed by climate change and the striving for security of energy supply are issues high on the political agenda these days. Governments are putting strategic plans in motion to decrease primary energy use, take carbon out of fuels and facilitate modal shifts. Taking a prominent place in these strategic plans is hydrogen as a future energy carrier. A number of manufacturers are now leasing demonstration vehicles to consumers using hydrogen-fueled internal combustion engines (H{sub 2}ICEs) as well as fuel cell vehicles. Developing countries in particular are pushing for H{sub 2}ICEs (powering two- and three-wheelers as well as passenger cars and buses) to decrease local pollution at an affordable cost. This article offers a comprehensive overview of H{sub 2}ICEs. Topics that are discussed include fundamentals of the combustion of hydrogen, details on the different mixture formation strategies and their emissions characteristics, measures to convert existing vehicles, dedicated hydrogen engine features, a state of the art on increasing power output and efficiency while controlling emissions and modeling.

Verhelst, S.; Wallner, T.; Energy Systems; Ghent Univ.

2009-12-01

81

Synthetic fuel aromaticity and staged combustion  

SciTech Connect

Samples of middle and heavy SRC-II distillates were distilled into 50 C boiling point range fractions. These were characterized by measurements of their molecular weight, elemental analysis and basic nitrogen content and calculation of average molecular structures. The structures typically consisted of 1 to 3 aromatic rings fused to alicyclic rings with short, 1 to 3 carbon aliphatic side chains. The lower boiling fractions contained significant amounts (1 atom/molecule) of oxygen while the heavier fractions contained so few heteroatoms that they were essentially hydrocarbons. Laboratory scale oxidative-pyrolysis experiments were carried out at pyrolysis temperatures of 500 to 1100 C and oxygen concentrations from 0 to 100 percent of stoichiometry. Analysis of liquid products, collected in condensers cooled with liquid nitrogen showed that aromatization is a major reaction in the absence of oxygen. The oxygen-containing materials (phenolics) seem to be more resistant to thermal pyrolysis than unsubstituted aromatics. Nitrogen converts from basic to nonbasic forms at about 500 C. The nonbasic nitrogen is more stable and survives up to 700 C after which it is slowly removed. A recently constructed 50,000 Btu/hr staged combustor was used to study the chemistry of the nitrogen and aromatics. SRC II combustion was studied under fuel-rich, first-stage conditions at air/fuel ratios from 0.6 to 1.0 times stoichiometric. The chemistry of the fuel during combustion calls for further investigation in order to examine the mechanism by which HCN is evolved as a common intermediate for the formation of the nitrogen-containing gaseous combustion products. 25 references, 45 figures, 25 tables.

Longanbach, J. R.; Chan, L. K.; Levy, A.

1982-11-15

82

Vaporized fuel control apparatus for internal combustion engines  

Microsoft Academic Search

A vaporized fuel control apparatus is described for an internal combustion engine, the apparatus comprising: a refuelling canister for adsorbing fuel vapor formed in the fuel tank during a refuelling thereof; a running canister for adsorbing fuel vapor formed in the fuel tank during a running of the engine; a first electromagnetic valve provided in a path for discharging the

T. Abe; M. Kiyono; M. Takao

1989-01-01

83

Carbonaceous fuel combustion with improved desulfurization  

DOEpatents

Lime utilization for sulfurous oxides adsorption in fluidized combustion of carbonaceous fuels is improved by impregnation of porous lime particulates with iron oxide. The impregnation is achieved by spraying an aqueous solution of mixed iron sulfate and sulfite on the limestone before transfer to the fluidized bed combustor, whereby the iron compounds react with the limestone substrate to form iron oxide at the limestone surface. The iron oxide present in the spent limestone is found to catalyze the regeneration rate of the spent limestone in a reducing environment. Thus both the calcium and iron components may be recycled.

Yang, Ralph T. (Middle Island, NY); Shen, Ming-shing (Rocky Point, NY)

1980-01-01

84

Broad Specification Fuels Combustion Technology Program, Phase 2  

NASA Technical Reports Server (NTRS)

An experimental evaluation of two advanced technology combustor concepts was conducted to evolve and assess their capability for operation on broadened properties fuels. The concepts were based on the results of Phase 1 of the Broad Specification Fuel Combustor Technology Program which indicated that combustors with variable geometry or staged combustion zones had a flexibility of operation that could facilitate operation on these fuels. Emphasis in defining these concepts included the use of single pipe as opposed to duplex or staged fuels systems to avoid the risk of coking associated with the reduction in thermal stability expected in broadened properties fuels. The first concept was a variable geometry combustor in which the airflow into the primary zone could be altered through valves on the front while the second was an outgrowth of the staged Vorbix combustor, evolved under the NASA/P&W ECCP and EEE programs incorporating simplified fuel and air introduction. The results of the investigation, which involved the use of Experimental Referee Broad Specification (ERBS) fuel, indicated that in the form initially conceived, both of these combustor concepts were deficient in performance relative to many of the program goals for performance emissions. However, variations of both combustors were evaluated that incorporated features to simulate conceptual enhancement to demonstrate the long range potential of the combustor. In both cases, significant improvements relative to the program goals were observed.

Lohmann, R. P.; Jeroszko, R. A.; Kennedy, J. B.

1990-01-01

85

Combustion characterization of beneficiated coal-based fuels. Quarterly report No. 4, February--April 1990  

SciTech Connect

The objectives of this project include: (1) the development of an engineering data base which will provide detailed information on the properties of BCFs influencing combustion, ash deposition, ash erosion, particulate collection, and missions; and (2) the application of this technical data base to predict the performance and economic impacts of firing the BCFs in various commercial boiler designs. The technical approach used to develop the technical data includes: bench-scale fuel property, combustion, and ash deposition tests; pilot-scale combustion and ash effects test; and full-scale combustion tests.

Chow, O.K.; Nsakala, N.Y.

1990-06-01

86

Self-oscillations of an unstable fuel combustion in the combustion chamber of a liquid-propellant rocket engine  

NASA Astrophysics Data System (ADS)

The form of the self-oscillations of a vibrating combustion of a fuel in the combustion chamber of a liquidpropellant rocket engine, caused by the fuel-combustion lag and the heat release, was determined. The character of change in these self-oscillations with increase in the time of the fuel-combustion lag was investigated.

Gotsulenko, V. V.; Gotsulenko, V. N.

2013-01-01

87

Fossil Fuel Combustion and the Major Sedimentary Cycle  

Microsoft Academic Search

The combustion of the fossil fuels coal, oil, and lignite potentially can mobilize many elements into the atmosphere at rates, in general, less than but comparable to their rates of flow through natural waters during the weathering cycle. Since the principal sites of fossil fuel combustion are in the mid-latitudes of the Northern Hemisphere, changes in the composition of natural

K. K. Bertine; Edward D. Goldberg

1971-01-01

88

Chemically enhanced combustion of water-slurry fuels  

Microsoft Academic Search

A method of enhancing the combustion of solid fuel\\/-water slurries by the addition of about 100 to 5,000 ppm of a stable water-soluble explosive, which will detonate early in the combustion process, thereby producing a secondary dispersion of fuel particles, and an 80-65% coal\\/20-35% water composition suitable for secondary dispersion during combustion containing about 100-5,000 ppm of a water-soluble explosive,

Olen

1984-01-01

89

Basic Considerations in the Combustion of Hydrocarbon Fuels with Air  

NASA Technical Reports Server (NTRS)

Basic combustion research is collected, collated, and interpreted as it applies to flight propulsion. The following fundamental processes are treated in separate chapters: atomization and evaporation of liquid fuels, flow and mixing processes in combustion chambers, ignition and flammability of hydrocarbon fuels, laminar flame propagation, turbulent flames, flame stabilization, diffusion flames, oscillations in combustors, and smoke and coke formation in the combustion of hydrocarbon-air mixtures. Theoretical background, basic experimental data, and practical significance to flight propulsion are presented.

Barnett, Henry C; Hibbard, Robert R

1957-01-01

90

Combustion of liquid-fuel droplets in supercritical conditions  

NASA Technical Reports Server (NTRS)

A comprehensive analysis of liquid-fuel droplet combustion in both subcritical and supercritical environments has been conducted. The formulation is based on the complete conservation equations for both gas and liquid phases, and accommodates variable thermophysical properties, finite-rate chemical kinetics, and a full treatment of liquid-vapor phase equilibrium at the drop surface. The governing equations and associated interfacial boundary conditions are solved numerically using a fully coupled, implicit scheme with the dual time-stepping integration technique. The model is capable of treating the entire droplet history, including the transition from the subcritical to supercritical state. As a specific example, the combustion of n-pentane fuel droplets in air is studied for pressures in the range of 5-140 atm. Results indicate that the ambient gas pressure exerts significant control of droplet gasification and burning processes through its influence on fluid transport, gas-liquid interfacial thermodynamics, and chemical reactions. The droplet gasification rate increases progressively with pressure. However, the data for the overall burnout time exhibit a considerable change in the combustion mechanism at the critical pressure, mainly as a result of reduced mass diffusivity and latent heat of vaporization with increased pressure.

Shuen, J. S.; Yang, Vigor; Hsaio, C. C.

1992-01-01

91

Oxy-combustion of high water content fuels  

NASA Astrophysics Data System (ADS)

As the issues of global warming and the energy crisis arouse extensive concern, more and more research is focused on maximizing energy efficiency and capturing CO2 in power generation. To achieve this, in this research, we propose an unconventional concept of combustion - direct combustion of high water content fuels. Due to the high water content in the fuels, they may not burn under air-fired conditions. Therefore, oxy-combustion is applied. Three applications of this concept in power generation are proposed - direct steam generation for the turbine cycle, staged oxy-combustion with zero flue gas recycle, and oxy-combustion in a low speed diesel-type engine. The proposed processes could provide alternative approaches to directly utilize fuels which intrinsically have high water content. A large amount of energy to remove the water, when the fuels are utilized in a conventional approach, is saved. The properties and difficulty in dewatering high water content fuels (e.g. bioethanol, microalgae and fine coal) are summarized. These fuels include both renewable and fossil fuels. In addition, the technique can also allow for low-cost carbon capture due to oxy-combustion. When renewable fuel is utilized, the whole process can be carbon negative. To validate and evaluate this concept, the research focused on the investigation of the flame stability and characteristics for high water content fuels. My study has demonstrated the feasibility of burning fuels that have been heavily diluted with water in a swirl-stabilized burner. Ethanol and 1-propanol were first tested as the fuels and the flame stability maps were obtained. Flame stability, as characterized by the blow-off limit -- the lowest O2 concentration when a flame could exist under a given oxidizer flow rate, was determined as a function of total oxidizer flow rate, fuel concentration and nozzle type. Furthermore, both the gas temperature contour and the overall ethanol concentration in the droplets along the spray were measured in the chamber for a stable flame. The experimental results indicate significant preferential vaporization of ethanol over water. Modeling results support this observation and indicate that the vaporization process is best described as the distillation limit mode with enhanced mass transfer by convection. Further, the influence of preferential vaporization on flame stability was investigated. A procedure was developed to evaluate the extent of preferential vaporization and subsequent flame stability of a fuel in aqueous solution. Various water soluble fuels were analyzed via this procedure in order to identify a chemical fuel showing strong preferential vaporization. t-Butanol was identified as having excellent physical and chemical properties, indicating stronger preferential vaporization than ethanol. Flame stability tests were run for aqueous solutions of both t-butanol and ethanol under identical flow conditions. Flame stability was characterized by the blow-off limit. In each comparison, the energy contents in the two solutions were kept the same. For the experiments under high swirl flow conditions (100% swirl flow), 12.5 wt% t-butanol has slightly lower blow-off limits than 15 wt% ethanol, and 8.3 wt% t-butanol has much lower blow-off limits than 10 wt% ethanol. For the experiments under a low swirl flow condition (50% swirl/50% axial flow), 12.5 wt% t-butanol has a much lower blow-off limit than 15 wt% ethanol. The time to release the fuel from a droplet was also calculated for both ethanol and t-butanol. For the same size droplet, the time to release t-butanol is much shorter than that of ethanol under the same conditions. Faster release of the fuel from water enhances flame stability, which is consistent with the experimental results. For the oxy-combustion characteristics of low-volatility fuel with high water content, glycerol was chosen as the fuel to study. It is found that self-sustained flame can be obtained for glycerol solution with concentration as high as 60 wt%, when burned in pure O2. However, the flame is lifted far away f

Yi, Fei

92

LIEKKI and JALO: Combustion and fuel conversion  

NASA Astrophysics Data System (ADS)

LIEKKI and JALO are well conceived and structured programs designed to strengthen Finland's special needs in combustion and gasification to utilize a diversity of fuels, increase the ratio of electrical to heat output, and to support the export market. Started in 1988, these two programs provide models of how universities, Technical research center's laboratories (VTT's), and industry can collaborate successfully in order to achieve national goals. The research is focused on long term goals in certain targeted niche areas. This is an effective way to use limited resources. The niche areas were chosen in a rational manner and appear to be appropriate for Finland. The LIEKKl and JALO programs have helped pull together research efforts that were previously more fragmented. For example, the combustion modeling area still appears fragmented. Individual project objectives should be tied to program goals at a very early stage to provide sharper focusing to the research. Both the LIEKKl and JALO programs appear to be strongly endorsed by industry. Industrial members of the Executive Committees were very supportive of these programs. There are good mechanisms for technology transfer in place, and the programs provide opportunities to establish good interfaces between industrial people and the individual researchers. The interest of industry is shown by the large number of applied projects that are supported by industry. This demonstrates the relevancy of the programs. There is a strong interaction between the JALO program and industry in black liquor gasification.

Grace, Thomas M.; Renz, Ulrich; Sarofim, Adel F.

93

Construction of combustion models for rapeseed methyl ester bio-diesel fuel for internal combustion engine applications.  

PubMed

Bio-diesel fuels are non-petroleum-based diesel fuels consisting of long chain alkyl esters produced by the transesterification of vegetable oils, that are intended for use (neat or blended with conventional fuels) in unmodified diesel engines. There have been few reports of studies proposing theoretical models for bio-diesel combustion simulations. In this study, we developed combustion models based on ones developed previously. We compiled the liquid fuel properties, and the existing detailed mechanism of methyl butanoate ester (MB, C(5)H(10)O(2)) oxidation was supplemented by sub-mechanisms for two proposed fuel constituent components, C(7)H(16) and C(7)H(8)O (and then, by mp2d, C(4)H(6)O(2) and propyne, C(3)H(4)) to represent the combustion model for rapeseed methyl ester described by the chemical formula, C(19)H(34)O(2) (or C(19)H(36)O(2)). The main fuel vapor thermal properties were taken as those of methyl palmitate C(19)H(36)O(2) in the NASA polynomial form of the Burcat database. The special global reaction was introduced to "crack" the main fuel into its constituent components. This general reaction included 309 species and 1472 reactions, including soot and NO(x) formation processes. The detailed combustion mechanism was validated using shock-tube ignition-delay data under diesel engine conditions. For constant volume and diesel engine (Volvo D12C) combustion modeling, this mechanism could be reduced to 88 species participating in 363 reactions. PMID:19409477

Golovitchev, Valeri I; Yang, Junfeng

2009-01-01

94

The Impact of Alternative Fuels on Combustion Kinetics  

SciTech Connect

The research targets the development of detailed kinetic models to quantitatively characterize the impact of alternative fuels on the performance of Navy turbines and diesel engines. Such impacts include kinetic properties such as cetane number, flame speed, and emissions as well as physical properties such as the impact of boiling point distributions on fuel vaporization and mixing. The primary focus will be Fischer-Tropsch liquids made from natural gas, coal or biomass. The models will include both the effects of operation with these alternative fuels as well as blends of these fuels with conventional petroleum-based fuels. The team will develop the requisite kinetic rules for specific reaction types and incorporate these into detailed kinetic mechanisms to predict the combustion performance of neat alternative fuels as well as blends of these fuels with conventional fuels. Reduced kinetic models will be then developed to allow solution of the coupled kinetics/transport problems. This is a collaboration between the Colorado School of Mines (CSM) and the Lawrence Livermore National Laboratory (LLNL). The CSM/LLNL team plans to build on the substantial progress made in recent years in developing accurate detailed chemical mechanisms for the oxidation and pyrolysis of conventional fuels. Particular emphasis will be placed upon reactions of the isoalkanes and the daughter radicals, especially tertiary radicals, formed by abstraction from the isoalkanes. The various components of the program are described. We have been developing the kinetic models for two iso-dodecane molecules, using the same kinetic modeling formalisms that were developed for the gasoline and diesel primary reference fuels. These mechanisms, and the thermochemical and transport coefficient submodels for them, are very close to completion at the time of this report, and we expect them to be available for kinetic simulations early in the coming year. They will provide a basis for prediction and selection of desirable F-T molecules for use in jet engine simulations, where we should be able to predict the ignition, combustion and emissions characteristics of proposed fuel components. These mechanisms include the reactions and chemical species needed to describe high temperature phenomena such as shock tube ignition and flammability behavior, and they will also include low temperature kinetics to describe other ignition phenomena such as compression ignition and knocking. During the past years, our hydrocarbon kinetics modeling group at LLNL has focused a great deal on fuels typical of gasoline and diesel fuel. About 10 years ago, we developed kinetic models for the fuel octane primary reference fuels, n-heptane [1] and iso-octane [2], which have 7 and 8 carbon atoms and are therefore representative of typical gasoline fuels. N-heptane represents the low limit of knock resistance with an octane number of 0, while iso-octane is very knock resistant with an octane number of 100. High knock resistance in iso-octane was attributed largely to the large fraction of primary C-H bonds in the molecule, including 15 of the 18 C-H bonds, and the high bond energy of these primary bonds plays a large role in this knock resistance. In contrast, in the much more ignitable n-heptane, 10 of its 16 C-H bonds are much less strongly bound secondary C-H bonds, leading to its very low octane number. All of these factors, as well as a similarly complex kinetic description of the equally important role of the transition state rings that transfer H atoms within the reacting fuel molecules, were quantified and collected into large kinetic reaction mechanisms that are used by many researchers in the fuel chemistry world.

Pitz, W J; Westbrook, C K

2009-07-30

95

Pilot fuel ignited stratified charge rotary combustion engine and fuel injector therefor  

Microsoft Academic Search

For a pilot fuel ignited stratified charge rotary, internal combustion engine, the fuel injection system and a fuel injector therefor comprises a fuel injector having plural discharge ports with at least one of the discharge ports located to emit a ''pilot'' fuel charge (relatively rich fuel-air mixture) into a passage in the engine housing, which passage communicates with the engine

Loyd

1980-01-01

96

Fuel/oxidizer-rich high-pressure preburners. [staged-combustion rocket engine  

NASA Technical Reports Server (NTRS)

The analyses, designs, fabrication, and cold-flow acceptance testing of LOX/RP-1 preburner components required for a high-pressure staged-combustion rocket engine are discussed. Separate designs of injectors, combustion chambers, turbine simulators, and hot-gas mixing devices are provided for fuel-rich and oxidizer-rich operation. The fuel-rich design addresses the problem of non-equilibrium LOX/RP-1 combustion. The development and use of a pseudo-kinetic combustion model for predicting operating efficiency, physical properties of the combustion products, and the potential for generating solid carbon is presented. The oxygen-rich design addresses the design criteria for the prevention of metal ignition. This is accomplished by the selection of materials and the generation of well-mixed gases. The combining of unique propellant injector element designs with secondary mixing devices is predicted to be the best approach.

Schoenman, L.

1981-01-01

97

Engine combustion control at low loads via fuel reactivity stratification  

DOEpatents

A compression ignition (diesel) engine uses two or more fuel charges during a combustion cycle, with the fuel charges having two or more reactivities (e.g., different cetane numbers), in order to control the timing and duration of combustion. By appropriately choosing the reactivities of the charges, their relative amounts, and their timing, combustion can be tailored to achieve optimal power output (and thus fuel efficiency), at controlled temperatures (and thus controlled NOx), and with controlled equivalence ratios (and thus controlled soot). At low load and no load (idling) conditions, the aforementioned results are attained by restricting airflow to the combustion chamber during the intake stroke (as by throttling the incoming air at or prior to the combustion chamber's intake port) so that the cylinder air pressure is below ambient pressure at the start of the compression stroke.

Reitz, Rolf Deneys; Hanson, Reed M; Splitter, Derek A; Kokjohn, Sage L

2014-10-07

98

Combustion of hydrocarbon fuels within porous inert media  

Microsoft Academic Search

There has been a recent surge of interest in the combustion of hydrocarbon fuels within porous inert media. The interest has been directed by the needs of industry to develop high performance radiant heaters while complying with increasingly stringent emissions regulations. This paper reviews the processes associated with non-catalytic combustion within porous media, and describes related experimental and modeling research.

J. R. Howell; M. J. Hall; J. L. Ellzey

1996-01-01

99

Oscillatory Flame Response in Acoustically Coupled Fuel Droplet Combustion  

E-print Network

internal combustion engine performance, i. standing waves inwithin engine and turbine systems. Fuel performance is ofengines in aviation and industry with the ultimate goal of reducing nitrogen oxide and sulfur emissions while fulfilling performance

Sevilla Esparza, Cristhian Israel

2013-01-01

100

Pollutant Emissions from Gasoline Combustion. 1. Dependence on Fuel  

E-print Network

-paraffins number: n for paraffins. A number of studies have been published concerning the combustion chemistry of paraffinic gasoline mechanism based on the chemistry of n-heptane and isooctanesthe two indicator fuels for octane

Utah, University of

101

Fuel Vapor Pressures and the Relation of Vapor Pressure to the Preparation of Fuel for Combustion in Fuel Injection Engines  

NASA Technical Reports Server (NTRS)

This investigation on the vapor pressure of fuels was conducted in connection with the general research on combustion in fuel injection engines. The purpose of the investigation was to study the effects of high temperatures such as exist during the first stages of injection on the vapor pressures of several fuels and certain fuel mixtures, and the relation of these vapor pressures to the preparation of the fuel for combustion in high-speed fuel injection engines.

Joachim, William F; Rothrock, A M

1930-01-01

102

Explosively Driven Combustion of Shock-Dispersed Fuels  

Microsoft Academic Search

The paper presents small-scale experiments with 1-g charges that explore the topic of post-detonation energy release due to the combustion of explosively dispersed fuels in the ambient air. To this end we have designed a new prototype small-scale charge, called Shock-Dispersed Fuel (SDF) charge. It consists of a lightweight, small paper cylinder filled with about one gram of a combustible

P. Neuwald

2006-01-01

103

Vaporizer design criteria for ethanol fueled internal combustion engines  

E-print Network

VAPORIZER DESIGN CRITERIA FOR ETHANOL FUELED INTERNAL COMBUSTION ENGINES A Thesis by ARACHCHI RALLAGE ARIYARATNE Submitted to the Graduate College of Texas ASM University in partial fulfillment of the requirements for the degree of MASTER... OF SCIENCE May 1985 Major Subject: Agricultural Engineering VAPORIZER DESIGN CRITERIA FOR ETHANOL FUELED INTERNAL COMBUSTION ENGINES A Thesis by ARACHCHI RALLAGE ARIYARATNE Approved as to style and content by: Wayne A. LePori (Chairman) Bill A...

Ariyaratne, Arachchi Rallage

1985-01-01

104

Hydrocarbon-fuel/combustion-chamber-liner materials compatibility  

NASA Technical Reports Server (NTRS)

Results of material compatibility experiments using hydrocarbon fuels in contact with copper-based combustion chamber liner materials are presented. Mil-Spec RP-1, n- dodecane, propane, and methane fuels were tested in contact with OFHC, NASA-Z, and ZrCu coppers. Two distinct test methods were employed. Static tests, in which copper coupons were exposed to fuel for long durations at constant temperature and pressure, provided compatibility data in a precisely controlled environment. Dynamic tests, using the Aerojet Carbothermal Test Facility, provided fuel and copper compatibility data under realistic booster engine service conditions. Tests were conducted using very pure grades of each fuel and fuels to which a contaminant, e.g., ethylene or methyl mercaptan, was added to define the role played by fuel impurities. Conclusions are reached as to degradation mechanisms and effects, methods for the elimination of these mechanisms, selection of copper alloy combustion chamber liners, and hydrocarbon fuel purchase specifications.

Gage, Mark L.

1990-01-01

105

Broad specification fuels combustion technology program  

NASA Technical Reports Server (NTRS)

Design and development efforts to evolve promising aircraft gas turbine combustor configurations for burning broadened-properties fuels were discussed. Design and experimental evaluations of three different combustor concepts in sector combustor rig tests was conducted. The combustor concepts were a state of the art single-annular combustor, a staged double-annular combustor, and a short single-annular combustor with variable geometry to control primary zone stoichiometry. A total of 25 different configurations of the three combustor concepts were evaluated. Testing was conducted over the full range of CF6-80A engine combustor inlet conditions, using four fuels containing between 12% and 14% hydrogen by weight. Good progress was made toward meeting specific program emissions and performance goals with each of the three combustor concepts. The effects of reduced fuel hydrogen content, including increased flame radiation, liner metal temperature, smoke, and NOx emissions were documented. The most significant effect on the baseline combustor was a projected 33% life reduction, for a reduction from 14% to 13% fuel hydrogen content, due to increased liner temperatures.

Dodds, W. J.; Ekstedt, E. E.

1984-01-01

106

Solid fuel combustion system for gas turbine engine  

DOEpatents

A solid fuel, pressurized fluidized bed combustion system for a gas turbine engine includes a carbonizer outside of the engine for gasifying coal to a low Btu fuel gas in a first fraction of compressor discharge, a pressurized fluidized bed outside of the engine for combusting the char residue from the carbonizer in a second fraction of compressor discharge to produce low temperature vitiated air, and a fuel-rich, fuel-lean staged topping combustor inside the engine in a compressed air plenum thereof. Diversion of less than 100% of compressor discharge outside the engine minimizes the expense of fabricating and maintaining conduits for transferring high pressure and high temperature gas and incorporation of the topping combustor in the compressed air plenum of the engine minimizes the expense of modifying otherwise conventional gas turbine engines for solid fuel, pressurized fluidized bed combustion.

Wilkes, Colin (Lebanon, IN); Mongia, Hukam C. (Carmel, IN)

1993-01-01

107

Dynamic stability, blowoff, and flame characteristics of oxy-fuel combustion  

E-print Network

Oxy-fuel combustion is a promising technology to implement carbon capture and sequestration for energy conversion to electricity in power plants that burn fossil fuels. In oxy-fuel combustion, air separation is used to ...

Shroll, Andrew Philip

2011-01-01

108

Size dependent electrical and magnetic properties of ZnFe2O4 nanoparticles synthesized by the combustion method: Comparison between aspartic acid and glycine as fuels  

NASA Astrophysics Data System (ADS)

Using two different fuels such as aspartic acid and glycine, the spinel zinc ferrite nanoparticles were synthesized by the combustion method at different pH values. The thermochemical calculations for both the fuel assisted materials and its adiabatic flame temperature were calculated. The X-ray diffraction (XRD) pattern revealed the formation of single phase ZnFe2O4 with high crystallinity. The characteristic functional groups of Fe3O and Zn3O were identified through FTIR analysis. Uniform size distribution of spherical particle in the average size range of 35-100 nm was inferred from SEM images. The room temperature DC conductivities of ZnFe2O4 particles prepared by using aspartic and glycine are in the order of 10-7 and 10-8 respectively. The dielectric spectral analysis inferred that the obtained dielectric constant is high at low frequency and decreases with increase in frequency. This dielectric behavior is in accordance with the Maxwell-Wagner interfacial polarization. VSM and M÷ssbauer analysis revealed that the prepared material exhibits paramagnetic behavior and Fe3+ state of iron content in ZnFe2O4 at room temperature.

Shanmugavani, A.; Kalai Selvan, R.; Layek, Samar; Sanjeeviraja, C.

2014-03-01

109

Investigation of combustion characteristics of methane-hydrogen fuels  

NASA Astrophysics Data System (ADS)

Numerical investigations of combustion characteristics of methane-hydrogen fuel used at present in tube furnaces of some petroleum refineries are carried out and possible problems related to change-over of existing furnaces from natural gas to methane-hydrogen fuel are analyzed. The effect of the composition of the blended fuel, associated temperature and emissivity of combustion products, temperature of combustion chamber walls, mean beam length, and heat release on variation in the radiation heat flux is investigated. The methane concentration varied from 0 to 100%. The investigations were carried out both at arbitrary given gas temperatures and at effective temperatures determined based on solving a set of equations at various heat-release rates of the combustion chamber and depended on the adiabatic combustion temperature and the temperature at the chamber output. The approximation dependence for estimation of the radiation heat exchange rate in the radiant chamber of the furnace at change-over to fuel with a greater hydrogen content is obtained. Hottel data were applied in the present work in connection with the impossibility to use approximated formulas recommended by the normative method for heat calculation of boilers to determine the gas emissivity, which are limited by the relationship of partial pressures of water steam and carbon dioxide in combustion products . The effect of the methane-hydrogen fuel on the equilibrium concentration of nitrogen oxides is also investigated.

Vetkin, A. V.; Suris, A. L.; Litvinova, O. A.

2015-01-01

110

Combustion characterization of beneficiated coal-based fuels. Quarterly report No. 6, July 1990--September 1990  

SciTech Connect

The Pittsburgh Energy Technology Center of the US Department of Energy has contracted with Combustion Engineering, Inc. (CE) to perform a three-year project on ``Combustion Characterization of Beneficiated Coal-Based Fuels.`` The beneficiated coals are produced by other contractors under the DOE Coal Preparation Program. Several contractor-developed advanced coal cleaning processes are being run at the cleaning facility in Homer City, Pennsylvania, to produce 20-ton batches of fuels for shipment to CE`s laboratory in Windsor, Connecticut. CE then processes the products into either a coal-water fuel (CVVT) or a dry microfine pulverized coal (DMPC) form for combustion testing. The objectives of this project include: (1) the development of an engineering data base which will provide detailed information on the properties of BCFs influencing combustion, ash deposition, ash erosion, particulate collection, and emissions; and (2) the application of this technical data base to predict the performance and economic impacts of firing the BCFs in various commercial boiler designs. The technical approach used to develop the technical data includes: bench-scale fuel property, combustion, and ash deposition tests; pilot-scale combustion and ash effects tests; and full-scale combustion tests. Subcontractors to CE to perform parts of the test work are the Massachusetts Institute of Technology (MIT), Physical Science, Inc. Technology Company (PSIT) and the University of North Dakota Energy and Environmental Research Center (UNDEERC). Twenty fuels will be characterized during the three-year base program: three feed coals, fifteen BCFS, and two conventionally cleaned coals for full-scale tests. Approximately, nine BCFs will be in dry microfine coal (DMPC) form, and six BCFs will be in coal-water fuel (CWF) form. Additional BCFs would be characterized during optional project supplements.

Chow, O.K.; Nsakala, N.Y.

1990-11-01

111

Combustion Properties of Biomass Flash Pyrolysis Oils: Final Project Report  

SciTech Connect

Thermochemical pyrolysis of solid biomass feedstocks, with subsequent condensation of the pyrolysis vapors, has been investigated in the U.S. and internationally as a means of producing a liquid fuel for power production from biomass. This process produces a fuel with significantly different physical and chemical properties from traditional petroleum-based fuel oils. In addition to storage and handling difficulties with pyrolysis oils, concern exists over the ability to use this fuel effectively in different combustors. The report endeavors to place the results and conclusions from Sandia's research into the context of international efforts to utilize pyrolysis oils. As a special supplement to this report, Dr. Steven Gust, of Finland's Neste Oy, has provided a brief assessment of pyrolysis oil combustion research efforts and commercialization prospects in Europe.

C. R. Shaddix; D. R. Hardesty

1999-04-01

112

FUEL INTERCHANGEABILITY FOR LEAN PREMIXED COMBUSTION IN GAS TURBINE ENGINES  

SciTech Connect

In response to environmental concerns of NOx emissions, gas turbine manufacturers have developed engines that operate under lean, pre-mixed fuel and air conditions. While this has proven to reduce NOx emissions by lowering peak flame temperatures, it is not without its limitations as engines utilizing this technology are more susceptible to combustion dynamics. Although dependent on a number of mechanisms, changes in fuel composition can alter the dynamic response of a given combustion system. This is of particular interest as increases in demand of domestic natural gas have fueled efforts to utilize alternatives such as coal derived syngas, imported liquefied natural gas and hydrogen or hydrogen augmented fuels. However, prior to changing the fuel supply end-users need to understand how their system will respond. A variety of historical parameters have been utilized to determine fuel interchangeability such as Wobbe and Weaver Indices, however these parameters were never optimized for todayĺs engines operating under lean pre-mixed combustion. This paper provides a discussion of currently available parameters to describe fuel interchangeability. Through the analysis of the dynamic response of a lab-scale Rijke tube combustor operating on various fuel blends, it is shown that commonly used indices are inadequate for describing combustion specific phenomena.

Don Ferguson; Geo. A. Richard; Doug Straub

2008-06-13

113

Superheated fuel injection for combustion of liquid-solid slurries  

SciTech Connect

A method and device for obtaining, upon injection, flash evaporation of a liquid in a slurry fuel to aid in ignition and combustion. The device is particularly beneficial for use of coal-water slurry fuels in internal combustion engines such as diesel engines and gas turbines, and in external combustion devices such as boilers and furnaces. The slurry fuel is heated under pressure to near critical temperature in an injector accumulator, where the pressure is sufficiently high to prevent boiling. After injection into a combustion chamber, the water temperature will be well above boiling point at a reducted pressure in the combustion chamber, and flash boiling will preferentially take place at solid-liquid surfaces, resulting in the shattering of water droplets and the subsequent separation of the water from coal particles. This prevents the agglomeration of the coal particles during the subsequent ignition and combustion process, and reduces the energy required to evaporate the water and to heat the coal particles to ignition temperature. The overall effect will be to accelerate the ignition and combustion rates, and to reduce the size of the ash particles formed from the coal.

Robben, F. A.

1985-12-17

114

Superheated fuel injection for combustion of liquid-solid slurries  

DOEpatents

A method and device are claimed for obtaining, upon injection, flash evaporation of a liquid in a slurry fuel to aid in ignition and combustion. The device is particularly beneficial for use of coal-water slurry fuels in internal combustion engines such as diesel engines and gas turbines, and in external combustion devices such as boilers and furnaces. The slurry fuel is heated under pressure to near critical temperature in an injector accumulator, where the pressure is sufficiently high to prevent boiling. After injection into a combustion chamber, the water temperature will be well above boiling point at a reduced pressure in the combustion chamber, and flash boiling will preferentially take place at solid-liquid surfaces, resulting in the shattering of water droplets and the subsequent separation of the water from coal particles. This prevents the agglomeration of the coal particles during the subsequent ignition and combustion process, and reduces the energy required to evaporate the water and to heat the coal particles to ignition temperature. The overall effect will be to accelerate the ignition and combustion rates, and to reduce the size of the ash particles formed from the coal. 2 figs., 2 tabs.

Robben, F.A.

1984-10-19

115

Superheated fuel injection for combustion of liquid-solid slurries  

DOEpatents

A method and device for obtaining, upon injection, flash evaporation of a liquid in a slurry fuel to aid in ignition and combustion. The device is particularly beneficial for use of coal-water slurry fuels in internal combustion engines such as diesel engines and gas turbines, and in external combustion devices such as boilers and furnaces. The slurry fuel is heated under pressure to near critical temperature in an injector accumulator, where the pressure is sufficiently high to prevent boiling. After injection into a combustion chamber, the water temperature will be well above boiling point at a reduced pressure in the combustion chamber, and flash boiling will preferentially take place at solid-liquid surfaces, resulting in the shattering of water droplets and the subsequent separation of the water from coal particles. This prevents the agglomeration of the coal particles during the subsequent ignition and combustion process, and reduces the energy required to evaporate the water and to heat the coal particles to ignition temperature. The overall effect will be to accelerate the ignition and combustion rates, and to reduce the size of the ash particles formed from the coal.

Robben, Franklin A. (Berkeley, CA)

1985-01-01

116

A combustion model for IC engine combustion simulations with multi-component fuels  

SciTech Connect

Reduced chemical kinetic mechanisms for the oxidation of representative surrogate components of a typical multi-component automotive fuel have been developed and applied to model internal combustion engines. Starting from an existing reduced mechanism for primary reference fuel (PRF) oxidation, further improvement was made by including additional reactions and by optimizing reaction rate constants of selected reactions. Using a similar approach to that used to develop the reduced PRF mechanism, reduced mechanisms for the oxidation of n-tetradecane, toluene, cyclohexane, dimethyl ether (DME), ethanol, and methyl butanoate (MB) were built and combined with the PRF mechanism to form a multi-surrogate fuel chemistry (MultiChem) mechanism. The final version of the MultiChem mechanism consists of 113 species and 487 reactions. Validation of the present MultiChem mechanism was performed with ignition delay time measurements from shock tube tests and predictions by comprehensive mechanisms available in the literature. A combustion model was developed to simulate engine combustion with multi-component fuels using the present MultiChem mechanism, and the model was applied to simulate HCCI and DI engine combustion. The results show that the present multi-component combustion model gives reliable performance for combustion predictions, as well as computational efficiency improvements through the use of reduced mechanism for multi-dimensional CFD simulations. (author)

Ra, Youngchul; Reitz, Rolf D. [Engine Research Center, University of Wisconsin-Madison (United States)

2011-01-15

117

Combustion of coal-gas fuels in a staged combustor  

SciTech Connect

Gaseous fuels produced from coal resources have been considered for use in industrial gas turbines. Such fuels generally have heating values much lower than the typical gaseous fuel, natural gas; the low heating value could result in unstable or inefficient combustion. Additionally, coal gas fuels may contain ammonia which if oxidized in an uncontrolled manner could result in unacceptable NO/sub x/ exhaust emission levels. Previous investigations have indicated that staged, rich-lean combustion represents a desirable approach to achieve stable, efficient, low NO/sub x/ emission operation for coal-derived liquid fuels containing up to 0.8-wt % nitrogen. An experimental program has been conducted to determine whether this fuel tolerance can be extended to include coal-derived gaseous fuels. The results of tests with three nitrogen-free fuels having heating values of 100, 250, and 350 Btu/scf and a 250 Btu/scf heating value doped to contain 0.7% ammonia are presented. The test results permit the following conclusions to be drawn: (1) Staged, rich-lean combustion represents the desirable approach to achieve ultra-low NO/sub x/ and CO emissions for coal gas fuels with heating values of 210 kJ/mol (238 Btu/scf) or higher. (2) Lean combustion represents the desirable approach to achieve ultra-low NO/sub x/ and CO emissions for coal gas fuels with low heating values (84 kJ/mol (95 Btu/scf)). (3) Staged combustion has the ability to limit NH/sub 3/ to NO/sub x/ conversion rates to less than 5%. NO/sub x/ emissions below the EPA limit can readily be achieved.

Rosfjord, T J; McVey, J B; Sederquist, R A; Schultz, D F

1982-01-01

118

Orifices For Fuel-Film Cooling Of Combustion Chamber  

NASA Technical Reports Server (NTRS)

Boundary-layer film of fuel flows along wall of combustion chamber mentioned in article, "Rhenium-Foil Witness Cylinders" (NPO-18224), cooling wall and neutralizing excess of oxidizer in vicinity of wall. Enters chamber through 16 small, replaceable nozzles placed around periphery of fuel-and-oxidizer injector. Adjusted, independently of main injected flow of fuel and oxidizer, by selection of nozzle passing larger or smaller flow.

Knight, B. L.

1992-01-01

119

Oxy-fuel combustion with integrated pollution control  

DOEpatents

An oxygen fueled integrated pollutant removal and combustion system includes a combustion system and an integrated pollutant removal system. The combustion system includes a furnace having at least one burner that is configured to substantially prevent the introduction of air. An oxygen supply supplies oxygen at a predetermine purity greater than 21 percent and a carbon based fuel supply supplies a carbon based fuel. Oxygen and fuel are fed into the furnace in controlled proportion to each other and combustion is controlled to produce a flame temperature in excess of 3000 degrees F. and a flue gas stream containing CO2 and other gases. The flue gas stream is substantially void of non-fuel borne nitrogen containing combustion produced gaseous compounds. The integrated pollutant removal system includes at least one direct contact heat exchanger for bringing the flue gas into intimated contact with a cooling liquid to produce a pollutant-laden liquid stream and a stripped flue gas stream and at least one compressor for receiving and compressing the stripped flue gas stream.

Patrick, Brian R. (Chicago, IL); Ochs, Thomas Lilburn (Albany, OR); Summers, Cathy Ann (Albany, OR); Oryshchyn, Danylo B. (Philomath, OR); Turner, Paul Chandler (Independence, OR)

2012-01-03

120

Global impact of fossil fuel combustion on atmospheric NO x Larry W. Horowitz  

E-print Network

Global impact of fossil fuel combustion on atmospheric NO x Larry W. Horowitz Advanced Study University, Cambridge, MA 02138 (email djj@io.harvard.edu) #12; Abstract. Fossil fuel combustion of fossil fuel combustion on the global distribution of NO x . In the model, we tag fossil fuel NO x and its

Jacob, Daniel J.

121

Surrogate Model Development for Fuels for Advanced Combustion Engines  

SciTech Connect

The fuels used in internal-combustion engines are complex mixtures of a multitude of different types of hydrocarbon species. Attempting numerical simulations of combustion of real fuels with all of the hydrocarbon species included is highly unrealistic. Thus, a surrogate model approach is generally adopted, which involves choosing a few representative hydrocarbon species whose overall behavior mimics the characteristics of the target fuel. The present study proposes surrogate models for the nine fuels for advanced combustion engines (FACE) that have been developed for studying low-emission, high-efficiency advanced diesel engine concepts. The surrogate compositions for the fuels are arrived at by simulating their distillation profiles to within a maximum absolute error of 4% using a discrete multi-component (DMC) fuel model that has been incorporated in the multi-dimensional computational fluid dynamics (CFD) code, KIVA-ERC-CHEMKIN. The simulated surrogate compositions cover the range and measured concentrations of the various hydrocarbon classes present in the fuels. The fidelity of the surrogate fuel models is judged on the basis of matching their specific gravity, lower heating value, hydrogen/carbon (H/C) ratio, cetane number, and cetane index with the measured data for all nine FACE fuels.

Anand, Krishnasamy [University of Wisconsin, Madison; Ra, youngchul [University of Wisconsin, Madison; Reitz, Rolf [University of Wisconsin; Bunting, Bruce G [ORNL

2011-01-01

122

High-pressure combustion of binary fuel sprays  

NASA Technical Reports Server (NTRS)

The ultimate objective of this study is to obtain fundamental information relevant to combustion processes that occur in fuel sprays of practical interest at high pressures in internal combustion engines. Since practical fuels are multicomponent and derived from petroleum, the present work involves the model alkane mixture of n-heptane and n-hexadecane. Since burning droplets in sprays can interact with each other, the present work involves investigation of the effects of this interaction on flame shapes and droplet burning times. The small droplets in practical combustion chambers are not significantly influenced by buoyancy. Since such small droplets are difficult to study experimentally, the present work takes advantage of microgravity to lessen buoyancy and enable information about droplet interactions to be obtained by studying larger droplets. The results are intended to provide fundamental understanding that can be used in improving descriptions of practical spray combustion.

Mikami, Masato; Kono, Michikata; Sato, Jun'ichi; Dietrich, Daniel L.; Williams, Forman A.

1995-01-01

123

Experimental Study of Unsupported Nonane fuel Droplet Combustion in Microgravity  

NASA Technical Reports Server (NTRS)

Soot formation in droplet flames is the basic component of the particulate emission process that occurs in spray combustion. The complexity of soot formation motivates a one-dimensional transport condition which has obvious advantages in modeling. Recent models of spherically symmetric droplet combustion have made this assumption when incorporating such aspects as detailed chemistry and radiation. Interestingly, spherical symmetry does not necessarily restrict the results because it has been observed that the properties of carbon formed in flames are not strongly affected by the nature of the fuel or flaming configuration. What is affected, however, are the forces acting on the soot aggregates and where they are trapped by a balance of drag and thermophoretic forces. The distribution of these forces depends on the transport conditions of the flame. Prior studies of spherical droplet flames have examined the droplet burning history of alkanes, alcohols and aromatics. Data are typically the evolution of droplet, flame, extinction, and soot shell diameters. These data are only now just beginning to find their way into comprehensive numerical models of droplet combustion to test proposed oxidation schemes for fuels such as methanol and heptane. In the present study, we report new measurements on the burning history of unsupported nonane droplets in a convection-free environment to promote spherical symmetry. The far-field gas is atmospheric pressure air at room temperature. The evolution of droplet diameter was measured using high speed cine photography of a spark-ignited, droplet within a confined volume in a drop tower. The initial droplet diameters varied between 0.5 mm and 0.6 mm. The challenge of unsupported droplets is to form, deploy and ignite them with minimal disturbance, and then to keep them in the camera field of view. Because of the difficulty of this undertaking, more sophisticated diagnostics for studying soot than photographic were not used. Supporting the test droplet by a fiber fixes the droplet position but the fiber can perturb the burning process especially for a sooting fuel. Prior studies on heptane showed little evidence for soot formation due to g-droplets of similar size the relationship between sooting and droplet diameter. For nonane droplets we expect increased sooting due to the greater number of carbon atoms. As a sooting droplet burns and its diameter decreases, proportionally less soot should form. This reduced soot, as well as the influence of soot formed earlier in the burning process which collects in a 'shell', on heat transport to the flame offers the potential for a time-varying burning rate. Such an effect was investigated and revealed in results reported here. Speculation is offered for the cause of this effect and its possible relation to soot formation.

Callahan, B. J.; Avedisian, C. T.; Hertzog, D. E.; Berkery, J. W.

1999-01-01

124

Straw pellets as fuel in biomass combustion units  

SciTech Connect

In order to estimate the suitability of straw pellets as fuel in small combustion units, the Danish Technological Institute accomplished a project including a number of combustion tests in the energy laboratory. The project was part of the effort to reduce the use of fuel oil. The aim of the project was primarily to test straw pellets in small combustion units, including the following: ash/slag conditions when burning straw pellets; emission conditions; other operational consequences; and necessary work performance when using straw pellets. Five types of straw and wood pellets made with different binders and antislag agents were tested as fuel in five different types of boilers in test firings at 50% and 100% nominal boiler output.

Andreasen, P.; Larsen, M.G. [Danish Technological Inst., Aarhus (Denmark)

1996-12-31

125

Alternate-Fueled Combustion-Sector Emissions  

NASA Technical Reports Server (NTRS)

In order to meet rapidly growing demand for fuel, as well as address environmental concerns, the aviation industry has been testing alternate fuels for performance and technical usability in commercial and military aircraft. Currently, alternate aviation fuels must satisfy MIL-DTL- 83133F(2008) (military) or ASTM D 7566- Annex(2011) (commercial) standards and are termed drop-in fuel replacements. Fuel blends of up to 50% alternative fuel blended with petroleum (JP-8), which have become a practical alternative, are individually certified on the market. In order to make alternate fuels (and blends) a viable option for aviation, the fuel must be able to perform at a similar or higher level than traditional petroleum fuel. They also attempt to curb harmful emissions, and therefore a truly effective alternate fuel would emit at or under the level of currently used fuel. This paper analyzes data from gaseous and particulate emissions of an aircraft combustor sector. The data were evaluated at various inlet conditions, including variation in pressure and temperature, fuel-to-air ratios, and percent composition of alternate fuel. Traditional JP-8+100 data were taken as a baseline, and blends of JP- 8+100 with synthetic-paraffinic-kerosene (SPK) fuel (Fischer-Tropsch (FT)) were used for comparison. Gaseous and particulate emissions, as well as flame luminosity, were assessed for differences between FT composition of 0%, 50%, and 100%. The data showed that SPK fuel (a FT-derived fuel) had slightly lower harmful gaseous emissions, and smoke number information corroborated the hypothesis that SPK-FT fuels are cleaner burning fuels.

Saxena, Nikita T.; Thomas, Anna E.; Shouse, Dale T.; Neuroth, Craig; Hendricks, Robert C.; Lynch, Amy; Frayne, Charles W.; Stutrud, Jeffrey S.; Corporan, Edwin; Hankins, Terry

2012-01-01

126

Effects of ambient conditions and fuel composition on combustion stability  

SciTech Connect

Recent regulations on NO, emissions are promoting the use of lean premix (LPM) combustion for industrial gas turbines. LPM combustors avoid locally stoichiometric combustion by premixing fuel and the air upstream of the reaction region, thereby eliminating the high temperatures that produce thermal NO.. Unfortunately, this style of combustor is prone to combustion oscillation. Significant pressure fluctuations can occur when variations in heat release periodically couple pressure to acoustic modes in the combustion chamber. These oscillations must be controlled because resulting vibration can shorten the life of engine hardware. Laboratory and engine field testing have shown that instability regimes can vary with environmental conditions. These observations prompted this study of the effects of ambient conditions and fuel composition on combustion stability. Tests are conducted on a sub-scale combustor burning natural gas, propane, and some hydrogen/hydrocarbon mixtures. A premix, swirl-stabilized fuel nozzle typical of industrial gas turbines is used. Experimental and numerical results describe how stability regions may shift as inlet air temperature, humidity, and fuel composition are altered. Results appear to indicate that shifting instability instability regimes are primarily caused by changes in reaction rate.

Janus, M.C.; Richards, G.A.; Yip, M.J. [USDOE Federal Energy Technology Center, Morgantown, WV (United States); Robey, E.H. [EG& G Technical Services of West Virginia (United States)

1997-04-01

127

Catalytic combustion of heavy partially-vaporized fuels  

NASA Technical Reports Server (NTRS)

An experimental program to demonstrate efficient catalytic combustion of fuel-lean and fuel-rich mixtures of residual fuel and air, and to assess the influence of incomplete fuel vaporization on the performance of a catalytic reactor is being conducted. A 7.5-cm diameter catalytic reactor was designed and will be tested over a matrix of conditions representative of a gas turbine combustor inlet. For each of three test phases, two series of tests with a uniform but poorly vaporized (less than 50 percent) mixture of No. 6 fuel oil and air will be performed. In the first series, the non-vaporized fuel will be contained in a spray of droplets with a Sauter Mean Diameter (SMD) less than 30 microns. In the second series, the non-vaporized fuel will be characterized by a spray SMD approximately equal to 100 microns. The designs of the fuel injection system and the catalytic reactor are described in this paper.

Rosfjord, T. J.

1980-01-01

128

Combustion characterization of beneficiated coal-based fuels. Quarterly report No. 13, April--June 1992  

SciTech Connect

The Pittsburgh Energy Technology Center of the US Department of Energy has contracted with Combustion Engineering, Inc. (CE) to perform a five-year project on ``Combustion Characterization of Beneficiated Coal-Based Fuels.`` The beneficiated coals are produced by other contractors under the DOE Coal Preparation Program. Several contractor-developed advanced coal cleaning processes are run at pilot-scale cleaning facilities to produce 20-ton batches of fuels for shipment to CE`s laboratory in Windsor, Connecticut. CE then processes the products into either a coal-water fuel (CWF) or a dry microfine pulverized coa1 (DMPC) form for combustion testing. The objectives of this project include: (1) the development of an engineering data base which will provide detailed information on the properties of BCFs influencing combustion, ash deposition, ash erosion, particulate collection, and emissions; and (2) the application of this technical data base to predict the performance and economic impacts of firing the BCFs in various commercial boiler designs. The technical approach used to develop the technical data includes: bench-scale fuel property, combustion, and ash deposition tests; pilot-scale combustion and ash effects tests; and full-scale combustion tests. During the third quarter of 1992, the following technical progress was made: Continued analyses of drop tube furnace samples to determine devolatilization kinetics; completed analyses of the samples from the pilot-scale ash deposition tests of unweathered Upper Freeport feed coal; published two technical papers at conferences; and prepared for upcoming tests of new BCFs being produced.

Chow, O.K.; Nsakala, N.Y.

1992-09-01

129

Method and system for low-NO.sub.x dual-fuel combustion of liquid and/or gaseous fuels  

DOEpatents

A method and apparatus for combustion in which a pressurized preheated liquid fuel is atomized and a portion thereof flash vaporized, creating a mixture of fuel vapor and liquid droplets. The mixture is mixed with primary combustion oxidant, producing a fuel/primary oxidant mixture which is then injected into a primary combustion chamber in which the fuel/primary oxidant mixture is partially combusted, producing a secondary gaseous fuel containing hydrogen and carbon oxides. The secondary gaseous fuel is mixed with a secondary combustion oxidant and injected into the second combustion chamber wherein complete combustion of the secondary gaseous fuel is carried out. The resulting second stage flue gas containing very low amounts of NO.sub.x is then vented from the second combustion chamber.

Gard, Vincent; Chojnacki, Dennis A; Rabovitser, Ioseph K

2014-12-02

130

Combustion in a Bomb with a Fuel-Injection System  

NASA Technical Reports Server (NTRS)

Fuel injected into a spherical bomb filled with air at a desired density and temperature could be ignited with a spark a few thousandths of a second after injection, an interval comparable with the ignition lag in fuel-injection engines. The effect of several variables on the extent and rate of combustion was investigated: time intervals between injection and ignition of fuel of 0.003 to 0.06 second and one of 5 minutes; initial air temperatures of 100 degrees C. to 250 degrees C.; initial air densities equivalent to 5, 10, and 15 absolute atmospheres pressure at 100 degrees C.; and air-fuel ratios of 5 to 25.

Cohn, Mildred; Spencer, Robert C

1935-01-01

131

Effect of fuel nitrogen and hydrogen content on emissions in hydrocarbon combustion  

NASA Technical Reports Server (NTRS)

The results of an investigation of the effect of operating conditions and fuel properties on emission for the two-stage combustion of fuels with significant organic nitrogen content are presented. The way in which the emissions of nitrogen oxides and carbon monoxide are affected by the decreased hydrogen content and the increased organic nitrogen content of coal-derived fuels is discussed. Limited measurements of smoke from the rich-lean combustion of simulated syncrude fuels indicate relatively high smoke emissions in spite of the very lean second-stage burning. This fact, together with the high observed carbon monoxide emissions, suggests that trade-offs will be necessary between the conditions that minimize NOx and those that control CO and smoke emissions.

Bittker, D. A.; Wolfbrandt, G.

1981-01-01

132

Kinetic Modeling of Combustion Characteristics of Real Biodiesel Fuels  

SciTech Connect

Biodiesel fuels are of much interest today either for replacing or blending with conventional fuels for automotive applications. Predicting engine effects of using biodiesel fuel requires accurate understanding of the combustion characteristics of the fuel, which can be acquired through analysis using reliable detailed reaction mechanisms. Unlike gasoline or diesel that consists of hundreds of chemical compounds, biodiesel fuels contain only a limited number of compounds. Over 90% of the biodiesel fraction is composed of 5 unique long-chain C{sub 18} and C{sub 16} saturated and unsaturated methyl esters. This makes modeling of real biodiesel fuel possible without the need for a fuel surrogate. To this end, a detailed chemical kinetic mechanism has been developed for determining the combustion characteristics of a pure biodiesel (B100) fuel, applicable from low- to high-temperature oxidation regimes. This model has been built based on reaction rate rules established in previous studies at Lawrence Livermore National Laboratory. Computed results are compared with the few fundamental experimental data that exist for biodiesel fuel and its components. In addition, computed results have been compared with experimental data for other long-chain hydrocarbons that are similar in structure to the biodiesel components.

Naik, C V; Westbrook, C K

2009-04-08

133

Global impact of fossil fuel combustion on atmospheric NOx Larry W. Horowitz  

E-print Network

Global impact of fossil fuel combustion on atmospheric NOx Larry W. Horowitz Advanced Study Program, MA 02138 (email djj@io.harvard.edu) #12;Abstract. Fossil fuel combustion is the largest global source-dimensional model of tropospheric chemistry and transport to study the impact of fossil fuel combustion

Jacob, Daniel J.

134

Improving the Carbon Dioxide Emission Estimates from the Combustion of Fossil Fuels in California  

E-print Network

Improving the Carbon Dioxide Emission Estimates from the Combustion of Fossil Fuels in California Estimates from the Combustion of Fossil Fuels in California" and augmentation to contract number 05 Dioxide Emission Estimates from the Combustion of Fossil Fuels in California" and augmentation to contract

135

Combustion and deposition, erosion, and corrosion tests of coal turbine fuels  

Microsoft Academic Search

This paper discusses the results obtained from the rich-quench-lean (RQL) combustion system running on distillate fuel and coal water slurry (CWS). Estimates of fuel bound nitrogen (FBN) yield indicate that rich lean combustion is successful in reducing the yield from coal water slurry fuel to between 8% and 12%. Some improvements in combustion efficiency are required when burning coal water

C. Wilkes; R. Wenglarz; D. W. Clark

1985-01-01

136

Chemically enhanced combustion of water-slurry fuels  

SciTech Connect

A method of enhancing the combustion of solid fuel/-water slurries by the addition of about 100 to 5,000 ppm of a stable water-soluble explosive, which will detonate early in the combustion process, thereby producing a secondary dispersion of fuel particles, and an 80-65% coal/20-35% water composition suitable for secondary dispersion during combustion containing about 100-5,000 ppm of a water-soluble explosive, preferably selected from at least one member of a group consisting of picric acid; alkali picrates, such as ammonium picrate, sodium picrate, potassium picrate, calcium picrate, etc., and heavy metal picrates, such as iron picrate, lead picrate, zinc picrate, etc.; guanidine and nitroguanidine. The addition of the explosive may be made to the water makeup of the slurry or may be added to the formed slurry.

Olen, K.R.

1984-06-19

137

Fuel correlations for combustion purposes, a summary of progress within the past fifteen years. Part 2  

SciTech Connect

Over the years, many correlations for fuel properties have been developed at Laval University. The main goal in this was to provide tools to estimate unknown fuel properties from the known values of the density and the viscosity at one temperature and the ASTM D-86 distillation, since these data are easily determined. The first part of this paper dealt with properties of liquid fuels. Most of the correlations in this second part are not so much pertinent to fuel properties per se, but rather to lean premixed flame behavior. Much of the behavior is related to two postulated temperatures, T{sub auig} and T{sub i}. The first (the auto ignition temperature) may be regarded as the start of a reaction and the second (the instantaneous, spontaneous ignition temperature) may be regarded as that temperature at which the reaction first becomes self-sustaining. Between them they account for a good deal of premixed combustion behavior. 48 refs.

Kretschmer, D.; Odgers, J. [Laval Univ., Quebec City, Quebec (Canada). Dept. of Mechanical Engineering

1996-12-31

138

Characterization of fuels for atmospheric fluidized bed combustion  

SciTech Connect

The Electric Power Research Institute (EPRI) has sponsored a fuels characterization program for the past several years with the intention of assisting utilities and boiler manufacturers in evaluating fuel quality impact on atmospheric fluidized bed combustion (AFBC) performance. The goal has been to provide an improved framework for making fuel switching decisions and consolidating operating experience. Results from this program include a set of bench-scale testing procedures, a fuel characterization data base, and a performance simulation model that links fuel characteristics to combustion performance. This paper reviews the major results of the fuels characterization program. The testing procedures, data base, and performance simulation models are briefly described and their application illustrated with examples. Performance predictions for the B W 1-ft{sup 2} bench-scale AFBC and the Tennessee Valley Authority (TVA) 20 MW(e) AFBC Pilot Plant are compared with actual test data. The relationship of coal rank to combustion is discussed. 11 refs., 12 figs., 5 tabs.

Daw, C.S. (Oak Ridge National Lab., TN (USA)); Rowley, D.R.; Perna, M.A. (Babcock and Wilcox Co., Alliance, OH (USA). Research Center); Stallings, J.W. (Electric Power Research Inst., Palo Alto, CA (USA)); Divilio, R.J. (Combustion Systems, Inc., Silver Spring, MD (USA))

1990-01-01

139

Air\\/fuel ratio sensor for an internal combustion engine  

Microsoft Academic Search

A sensor is described for detecting the air\\/fuel ratio of the exhaust gas from an internal combustion engine comprising: a housing, said housing defining a closed air chamber, said air chamber being fluidly sealed from the exhaust gas, an oxygen diffusion cell constructed of an electrolytic material, said diffusion cell having one side exposed to the exhaust gas and a

Hunt

1993-01-01

140

Solid Surface Combustion Experiment: Thick Fuel Results  

NASA Technical Reports Server (NTRS)

The results of experiments for spread over polymethylmethacrylate, PMMA, samples in the microgravity environment of the Space Shuttle are described. The results are coupled with modelling in an effort to describe the physics of the spread process for thick fuels in a quiescent, microgravity environment and uncover differences between thin and thick fuels. A quenching phenomenon not present for thin fuels is delineated, namely the fact that for thick fuels the possibility exists that, absent an opposing flow of sufficient strength to press the flame close enough to the fuel surface to allow the heated layer in the solid to develop, the heated layer fails to become 'fully developed.' The result is that the flame slows, which in turn causes an increase in the relative radiative loss from the flame, leading eventually to extinction. This potential inability of a thick fuel to develop a steady spread rate is not present for a thin fuel because the heated layer is the fuel thickness, which reaches a uniform temperature across the thickness relatively rapidly.

Altenkirch, Robert A.; Bhattacharjee, Subrata; West, Jeff; Tang, Lin; Sacksteder, Kurt; Delichatsios, Michael A.

1997-01-01

141

Combustion of liquid fuels in diesel engine  

NASA Technical Reports Server (NTRS)

Hitherto, definite specifications have always been made for fuel oils and they have been classified as more or less good or non-utilizable. The present aim, however, is to build Diesel engines capable of using even the poorest liquid fuels and especially the waste products of the oil industry, without special chemical or physical preparation.

Alt, Otto

1924-01-01

142

Experimental Investigation of the Effects of Fuel Characteristics on High Efficiency Clean Combustion (HECC) in a Light-Duty Diesel Engine  

SciTech Connect

An experimental study was performed to understand fuel property effects on low temperature combustion (LTC) processes in a light-duty diesel engine. These types of combustion modes are often collectively referred to as high efficiency clean combustion (HECC). A statistically designed set of research fuels, the Fuels for Advanced Combustion Engines (FACE), were used for this study. Engine conditions consistent with low speed cruise (1500 rpm, 2.6 bar BMEP) were chosen for investigating fuel property effects on HECC operation in a GM 1.9-L common rail diesel engine. The FACE fuel matrix includes nine combinations of fuel properties including cetane number (30 to 55), aromatic contents (20 to 45 %), and 90 % distillation temperature (270 to 340 C). HECC operation was achieved with high levels of EGR and adjusting injection parameters, e.g. higher fuel rail pressure and single injection event, which is also known as Premixed Charge Compression Ignition (PCCI) combustion. Engine performance, pollutant emissions, and details of the combustion process are discussed in this paper. Cetane number was found to significantly affect the combustion process with variations in the start of injection (SOI) timing, which revealed that the ranges of SOI timing for HECC operation and the PM emission levels were distinctively different between high cetane number (55) and low cetane number fuels (30). Low cetane number fuels showed comparable levels of regulated gas emissions with high cetane number fuels and had an advantage in PM emissions.

Cho, Kukwon [ORNL; Han, Manbae [ORNL; Wagner, Robert M [ORNL; Sluder, Scott [ORNL

2009-01-01

143

Combustion characteristics of hydrogen-carbon monoxide based gaseous fuels  

NASA Technical Reports Server (NTRS)

The results of trials with a staged combustor designed to use coal-derived gaseous fuels and reduce the NO(x) emissions from nitrogen-bound fuels to 75 ppm and 37 ppm without bound nitrogen in 15% O2 are reported. The combustor was outfitted with primary zone regenerative cooling, wherein the air cooling the primary zone was passed into the combustor at 900 F and mixed with the fuel. The increase in the primary air inlet temperature eliminated flashback and autoignition, lowered the levels of CO, unburned hydrocarbons, and smoke, and kept combustion efficiencies to the 99% level. The combustor was also equipped with dual fuel injection to test various combinations of liquid/gas fuel mixtures. Low NO(x) emissions were produced burning both Lurgi and Winkler gases, regardless of the inlet pressure and temperature conditions. Evaluation of methanation of medium energy gases is recommended for providing a fuel with low NO(x) characteristics.

White, D. J.; Kubasco, A. J.; Lecren, R. T.; Notardonato, J. J.

1982-01-01

144

Atomization and combustion properties of flashing injectors  

NASA Astrophysics Data System (ADS)

Flashing injection involves expanding a fluid through an injector until a supersaturated state is reached, causing a portion of the fluid to flash to a vapor. This investigation considered the flow, atomization and spreading properties of flashing injectors flowing liquids containing dissolved gases (Jet A/air) as well as superheated liquids (Freon 11). The use of a two stage expansion process, separated by an expansion chamber, was found to be beneficial for good atomization properties of flashing injection - particularly for dissolved gas systems. Both locally homogeneous and separated flow models provided good predictions of injector flow properties. Conventional correlations for drop sizes from pressure atomized and airblast injectors were successfully modified, using the separated flow model to prescribe injector exit conditions, to correlate drop size measurements. Additional experimental results are provided for spray angle and combustion properties of sprays from flashing injectors.

Solomon, A. S. P.; Rupprecht, S. D.; Chen, L.-D.; Faeth, G. M.

1982-01-01

145

Elimination of abnormal combustion in a hydrogen-fueled engine  

SciTech Connect

This report covers the design, construction, and testing of a dedicated hydrogen-fueled engine. Both part-load and full-load data were taken under laboratory conditions. The engine design included a billet aluminum single combustion chamber cylinder-head with one intake valve, two sodium coiled exhaust valves, and two spark plugs. The cylinder-head design also included drilled cooling passages. The fuel-delivery system employed two modified Siemens electrically actuated fuel injectors, The exhaust system included two separate headers, one for each exhaust port. The piston/ring combination was designed specifically for hydrogen operation.

Swain, M.R.; Swain, M.N. [Analytical Technologies, Inc., Miami, FL (United States)

1995-11-01

146

Municipal solid waste combustion: Fuel testing and characterization  

SciTech Connect

The objective of this study is to screen and characterize potential biomass fuels from waste streams. This will be accomplished by determining the types of pollutants produced while burning selected municipal waste, i.e., commercial mixed waste paper residential (curbside) mixed waste paper, and refuse derived fuel. These materials will be fired alone and in combination with wood, equal parts by weight. The data from these experiments could be utilized to size pollution control equipment required to meet emission standards. This document provides detailed descriptions of the testing methods and evaluation procedures used in the combustion testing and characterization project. The fuel samples will be examined thoroughly from the raw form to the exhaust emissions produced during the combustion test of a densified sample.

Bushnell, D.J.; Canova, J.H.; Dadkhah-Nikoo, A.

1990-10-01

147

Numerical analysis of supersonic combustion ramjet with upstream fuel injection  

NASA Astrophysics Data System (ADS)

This paper describes possible fuel injection scheme for airbreathing engines that use hydrocarbon fuels. The basic idea is to inject fuel at the spike tip of the supersonic inlet to achieve mixing and combustion efficiency with a limited length combustion chamber. A numerical code, able to solve the full Navier-Stokes equations in turbulent and reacting flows, is employed to obtain numerical simulations of the thermo-fluidynamic fields at different scramjet flight conditions, at Mach numbers of M=6.5 and 8. The feasibility of the idea of the upstream injection is checked for a simple axisymmetric configuration and relatively small size. The results are discussed in connection with the potential benefits deriving from the use of new ultra high temperature ceramics (UHTC).

Savino, Raffaele; Pezzella, Giuseppe

2003-09-01

148

Combustion characterization of beneficiated coal-based fuels. Quarterly report No. 11, October--December 1991  

SciTech Connect

The objectives of this project include: (1) the development of an engineering data base which will provide detailed information on the properties of beneficiated coal-based fuels (BCFs) influencing combustion, ash deposition, ash erosion, particulate collection, and emissions; and (2) the application of this technical data base to predict the performance and economic impacts of firing the BCFs in various commercial boiler designs. The technical approach used to develop the technical data includes: bench-scale fuel property, combustion, and ash deposition tests; pilot-scale combustion and ash effects tests; and full-scale combustion tests. Subcontractors perform parts of the test work are the Massachusetts Institute of Technology Physical Science, Inc. Technology Company and the University of North Dakota Energy and Environmental Research Center. Twenty fuels will be characterized during the three-year base program: three feed coals, fifteen BCFs, and two conventionally cleaned coals for full-scale tests. Approximately nine BCFs will be in dry ultra fine coal (DUC) form, and six BCFs will be in coal-water fuel (CWF) form. Additional BCFs would be characterized during optional project supplements. During the third quarter of 1991, the following technical progress was made: Continued analyses of drop tube furnace samples to determine devolatilization kinetics; completed analyses of the samples from the pilot-scale ash deposition tests of three Freeport Pittsburgh 8 fuels; conducted pilot-scale combustion and ash deposition tests of a fresh batch of Upper Freeport parent coal in the CE fireside Performance Test Facility; and completed editing of the fourth quarterly report and sent it to the publishing office.

Chow, O.K.; Nsakala, N.Y.

1992-03-01

149

FUNDAMENTAL INVESTIGATION OF FUEL TRANSFORMATIONS IN PULVERIZED COAL COMBUSTION AND GASIFICATION TECHNOLOGIES  

SciTech Connect

The goal of this project was to carry out the necessary experiments and analyses to extend current capabilities for modeling fuel transformations to the new conditions anticipated in next-generation coal-based, fuel-flexible combustion and gasification processes. This multi-organization, multi-investigator project has produced data, correlations, and submodels that extend present capabilities in pressure, temperature, and fuel type. The combined experimental and theoretical/computational results are documented in detail in Chapters 1-8 of this report, with Chapter 9 serving as a brief summary of the main conclusions. Chapters 1-3 deal with the effect of elevated pressure on devolatilization, char formation, and char properties. Chapters 4 and 5 deal with advanced combustion kinetic models needed to cover the extended ranges of pressure and temperature expected in next-generation furnaces. Chapter 6 deals with the extension of kinetic data to a variety of alternative solid fuels. Chapter 7 focuses on the kinetics of gasification (rather than combustion) at elevated pressure. Finally, Chapter 8 describes the integration, testing, and use of new fuel transformation submodels into a comprehensive CFD framework. Overall, the effects of elevated pressure, temperature, heating rate, and alternative fuel use are all complex and much more work could be further undertaken in this area. Nevertheless, the current project with its new data, correlations, and computer models provides a much improved basis for model-based design of next generation systems operating under these new conditions.

Robert Hurt; Joseph Calo; Thomas H. Fletcher; Alan Sayre

2005-04-29

150

Explosively Driven Combustion of Shock-Dispersed Fuels  

NASA Astrophysics Data System (ADS)

The paper presents small-scale experiments with 1-g charges that explore the topic of post-detonation energy release due to the combustion of explosively dispersed fuels in the ambient air. To this end we have designed a new prototype small-scale charge, called Shock-Dispersed Fuel (SDF) charge. It consists of a lightweight, small paper cylinder filled with about one gram of a combustible powder (e.g., flake aluminum) surrounding a spherical PETN booster of 0.5 g. We have tested the SDF charges in a number of different environments, realized as closed steel vessels of simple geometry (barometric bombs). Three of the bombs vary in volume (6.6 1, 21.2 1 and 40.5 1), while their aspect ratio L/D is kept constant at about 1. Two further bombs are comparable to the smallest bomb in volume (6.3 1), but provide different aspect ratios: L/D = 4.6 and 12.5. In addition, we have also performed tests in a tunnel-model with an L/D = 37.5. Our basic goal is to assess the performance of the charges by means of the combustion-related pressure built-up. Thus we contrast experiments on SDF charges in air with tests in nitrogen, to inhibit combustion, and with tests on conventional charges. Experiments and theoretical estimates on the expected overpressure allow one to formulate various indicators of the combustion effectiveness. For SDF charges these indicate that the combustion effectiveness decreases with increasing volume of the barometric bomb, and also with increasing aspect ratio at constant volume. This bears importance to the performance of SDF charges in tunnel environments. The performance losses reflect Ś at least in part Ś geometry-specific constraints on the mixing between fuel and air.

Neuwald, P.

2006-07-01

151

Numerical modeling of hydrogen-fueled internal combustion engines  

SciTech Connect

Major progress was achieved in the last year in advancing the modeling capabilities of hydrogen-fueled engines, both in support of the multi-laboratory project with SNL and LLNL to develop a high-efficiency, low emission powerplant and to provide the engine design tools to industry and research laboratories for hydrogen-fueled engines and stationary power generators. The culmination of efforts on many fronts was the excellent comparison of the experimental data from the Onan engine, operated by SNL.These efforts include the following. An extensive study of the intake flow culminated in a major understanding of the interdependence of the details of the intake port design and the engine operating condition on the emissions and efficiency. This study also resulted in design suggestions for future engines and general scaling laws for turbulence that enables the KIVA results to be applied to a wide variety of operating conditions. The research on the turbulent combustion of hydrogen brought into perspective the effect of the unique aspects of hydrogen combustion and their influence on possible models of turbulent combustion. The effort culminated in a proposed model for turbulent hydrogen combustion that is in agreement with available literature. Future work will continue the development in order to provide a generally predictive model for hydrogen combustion. The application of the combustion model to the Onan experiments elucidated the observed improvement of the efficiency of the engine with the addition of a shroud on the intake valve. This understanding will give guidance to future engine design for optimal efficiency. Finally, a brief summary is given of the extensions and refinements of the KIVA-3 code, in support of future designers of hydrogen-fueled engines.

Johnson, N.L.; Amsden, A.A.; Butler, T.D. [Los Alamos National Lab., NM (United States). Theoretical Div.

1996-07-01

152

Enhancing the combustible properties of bamboo by torrefaction.  

PubMed

Bamboo has wide range of moisture content, low bulk energy density and is difficult to transport, handle, store and feed into existing combustion and gasification systems. Because of its important fuel characteristics such as low ash content, alkali index and heating value, bamboo is a promising energy crop for the future. The aim of this study was to evaluate the effects of torrefaction on the main energy properties of Bambusa vulgaris. Three different torrefaction temperatures were employed: 220, 250 and 280░C. The elemental characteristics of lignite and coal were compared to the torrefied bamboo. The characteristics of the biomass fuels tend toward those of low rank coals. Principal component analysis of FTIR data showed a clear separation between the samples by thermal treatment. The loadings plot indicated that the bamboo samples underwent chemical changes related to carbonyl groups, mostly present in hemicelluloses, and to aromatic groups present in lignin. PMID:21703854

Rousset, Patrick; Aguiar, Clarissa; LabbÚ, Nicole; CommandrÚ, Jean-Michel

2011-09-01

153

The NASA broad-specification fuels combustion technology program: An assessment of phase 1 test results  

NASA Technical Reports Server (NTRS)

An assessment is made of the results of Phase 1 screening testing of current and advanced combustion system concepts using several broadened-properties fuels. The severity of each of several fuels-properties effects on combustor performance or liner life is discussed, as well as design techniques with the potential to offset these adverse effects. The selection of concepts to be pursued in Phase 2 refinement testing is described. This selection takes into account the relative costs and complexities of the concepts, the current outlook on pollutant emissions control, and practical operational problems.

Fear, J. S.

1983-01-01

154

Fuel properties of cottonseed oil  

SciTech Connect

The use of vegetable oils as fuel alternatives has an exceptional importance in the field of research. In this study, evaluation possibilities of cottonseed oil have been investigated as an alternative candidate for diesel fuel and fuel oil. The fuel property tests were performed according to standard analysis methods for oil and fuel. An overall evaluation of the results indicates that cottonseed oil can be proposed as a possible green substitute for fuel.

Karaosmanoglu, F.; Tueter, M.; Goellue, E. [Istanbul Technical Univ. (Turkey). Dept. of Chemical Engineering; Yanmaz, S.; Altintig, E. [Sakarya Univ. (Turkey). Dept. of Chemistry

1999-11-01

155

Fuel injector nozzle for an internal combustion engine  

DOEpatents

A direct injection fuel injector includes a nozzle tip having a plurality of passages allowing fluid communication between an inner nozzle tip surface portion and an outer nozzle tip surface portion and directly into a combustion chamber of an internal combustion engine. A first group of the passages have inner surface apertures located substantially in a first common plane. A second group of the passages have inner surface apertures located substantially in at least a second common plane substantially parallel to the first common plane. The second group has more passages than the first group.

Cavanagh, Mark S. (Bloomington, IL); Urven, Jr., Roger L. (Colona, IL); Lawrence, Keith E. (Peoria, IL)

2011-03-22

156

Fuel injector nozzle for an internal combustion engine  

SciTech Connect

A direct injection fuel injector includes a nozzle tip having a plurality of passages allowing fluid communication between an inner nozzle tip surface portion and an outer nozzle tip surface portion and directly into a combustion chamber of an internal combustion engine. A first group of the passages have inner surface apertures located substantially in a first common plane. A second group of the passages have inner surface apertures located substantially in at least a second common plane substantially parallel to the first common plane. The second group has more passages than the first group.

Cavanagh, Mark S. (Bloomington, IL); Urven, Jr., Roger L. (Colona, IL); Lawrence, Keith E. (Peoria, IL)

2008-11-04

157

Fuel injector nozzle for an internal combustion engine  

DOEpatents

A direct injection fuel injector includes a nozzle tip having a plurality of passages allowing fluid communication between an inner nozzle tip surface portion and an outer nozzle tip surface portion and directly into a combustion chamber of an internal combustion engine. A first group of the passages have inner surface apertures located substantially in a first common plane. A second group of the passages have inner surface apertures located substantially in at least a second common plane substantially parallel to the first common plane. The second group has more passages than the first group.

Cavanagh, Mark S. (Bloomington, IL); Urven, Jr., Roger L. (Colona, IL); Lawrence, Keith E. (Peoria, IL)

2007-11-06

158

Fuel Injector Nozzle For An Internal Combustion Engine  

DOEpatents

A direct injection fuel injector includes a nozzle tip having a plurality of passages allowing fluid communication between an inner nozzle tip surface portion and an outer nozzle tip surface portion and directly into a combustion chamber of an internal combustion engine. A first group of the passages have inner surface apertures located substantially in a first common plane. A second group of the passages have inner surface apertures located substantially in at least a second common plane substantially parallel to the first common plane. The second group has more passages than the first group.

Cavanagh, Mark S. (Bloomington, IL); Urven, Jr.; Roger L. (Colona, IL); Lawrence, Keith E. (Peoria, IL)

2006-04-25

159

Disturbing effect of free hydrogen on fuel combustion in internal combustion engines  

NASA Technical Reports Server (NTRS)

Experiments with fuel mixtures of varying composition, have recently been conducted by the Motor Vehicle and Airplane Engine Testing Laboratories of the Royal Technical High School in Berlin and at Fort Hahneberg, as well as at numerous private engine works. The behavior of hydrogen during combustion in engines and its harmful effect under certain conditions, on the combustion in the engine cylinder are of general interest. Some of the results of these experiments are given here, in order to elucidate the main facts and explain much that is already a matter of experience with chauffeurs and pilots.

Riedler, A

1923-01-01

160

Fundamental characterization of alternate fuel effects in continuous combustion systems. Summary technical progress report, August 15, 1978-January 31, 1980  

SciTech Connect

The overall objective of this contract is to assist in the development of fuel-flexible combustion systems for gas turbines as well as Rankine and Stirling cycle engines. The primary emphasis of the program is on liquid hydrocarbons produced from non-petroleum resources. Fuel-flexible combustion systems will provide for more rapid transition of these alternative fuels into important future energy utilization centers (especially utility power generation with the combined cycle gas turbine). The specific technical objectives of the program are: (a) develop an improved understanding of relationships between alternative fuel properties and continuous combustion system effects, and (b) provide analytical modeling/correlation capabilities to be used as design aids for development of fuel-tolerant combustion systems. This is the second major report of the program. Key experimental findings during this reporting period concern stirred combustor soot production during operation at controlled temperature conditions, soot production as a function of combustor residence time, an improved measurement technique for total hydrocarbons and initial stirred combustor results of fuel nitrogen conversion. While the results to be presented concern a stirred combustor which utilizes premixed fuel vapor/oxidant mixtures, a new combustor which combusts liquid fuel injected into the reactor as a spray has been developed and will be described. Analytical program progress includes the development of new quasiglobal models of soot formation and assessment of needs for other submodel development.

Blazowski, W.S.; Edelman, R.B.; Wong, E.

1980-02-27

161

Internal combustion engine in which compressed fuel mixture is combusted externally of the cylinders of the engine in a rotating combustion chamber  

SciTech Connect

An internal combustion engine is described comprising a cylinder body having a pair of adjoining first and second cylinders, a reciprocable piston in each cylinder, first valve means for introducing a fuel mixture in the first cylinder, second valve means for discharge of exhaust gases from the second cylinder, a combustion chamber mounted adjacent the cylinder body for movement between the cylinders and communicating in one position with the first cylinder and in a second position with the second cylinder, the combustion chamber receiving compressed fuel mixture from the first cylinder in the one position, and means for igniting the compressed fuel mixture in the combustion chamber as the chamber moves from the first to the second position, the combustion chamber delivering combusted fuel mixture to the second cylinder in the second position.

Staheli, A.A.

1988-04-26

162

Hydrogen-fueled internal combustion engines  

Microsoft Academic Search

The threat posed by climate change and the striving for security of energy supply are issues high on the political agenda these days. Governments are putting strategic plans in motion to decrease primary energy use, take carbon out of fuels and facilitate modal shifts.Taking a prominent place in these strategic plans is hydrogen as a future energy carrier. A number

Sebastian Verhelst; Thomas Wallner

2009-01-01

163

Electrostatic fuel conditioning of internal combustion engines  

NASA Technical Reports Server (NTRS)

Diesel engines were tested to determine if they are influenced by the presence of electrostatic and magnetic fields. Field forces were applied in a variety of configurations including pretreatment of the fuel and air, however, no affect on engine performance was observed.

Gold, P. I.

1982-01-01

164

Combustion characteristics of a turbocharged DI compression ignition engine fueled with petroleum diesel fuels and biodiesel  

Microsoft Academic Search

In this study, the combustion characteristics and emissions of two different petroleum diesel fuels (No. 1 and No. 2) and biodiesel from soybean oil were compared. The tests were performed at steady state conditions in a four-cylinder turbocharged DI diesel engine at full load at 1400-rpm engine speed. The experimental results compared with No. 2 diesel fuel showed that biodiesel

Mustafa Canakci

2007-01-01

165

Plasma-Enhanced Combustion of Hydrocarbon Fuels and Fuel Blends Using Nanosecond Pulsed Discharges  

SciTech Connect

This project had as its goals the study of fundamental physical and chemical processes relevant to the sustained premixed and non-premixed jet ignition/combustion of low grade fuels or fuels under adverse flow conditions using non-equilibrium pulsed nanosecond discharges.

Cappelli, Mark; Mungal, M Godfrey

2014-10-28

166

Synthesis of Diopside by Solution Combustion Process Using Glycine Fuel  

NASA Astrophysics Data System (ADS)

Nano ceramic Diopside (CaMgSi2O6) powders are synthesized by Solution Combustion Process(SCS) using Calcium nitrate, Magnesium nitrate as oxidizer and glycine as fuel, fumed silica as silica source. Ammonium nitrate (AN) is used as extra oxidizer. Effect of AN on Diopside phase formation is investigated. The adiabatic flame temperatures are calculated theoretically for varying amount of AN according to thermodynamic concept and correlated with the observed flame temperatures. A ôMulti channel thermocouple setup connected to computer interfaced Keithley multi voltmeter 2700ö is used to monitor the thermal events during the process. An interpretation based on maximum combustion temperature and the amount of gases produced during reaction for various AN compositions has been proposed for the nature of combustion and its correlation with the characteristics of as synthesized powder. These powders are characterized by XRD, SEM showing that the powders are composed of polycrystalline oxides with crystallite size of 58nm to 74nm.

Sherikar, Baburao N.; Umarji, A. M.

167

A jet fuel surrogate formulated by real fuel properties  

SciTech Connect

An implicit methodology based on chemical group theory to formulate a jet aviation fuel surrogate by the measurements of several combustion related fuel properties is tested. The empirical formula and derived cetane number of an actual aviation fuel, POSF 4658, have been determined. A three component surrogate fuel for POSF 4658 has been formulated by constraining a mixture of n-decane, iso-octane and toluene to reproduce the hydrogen/carbon ratio and derived cetane number of the target fuel. The validity of the proposed surrogate is evaluated by experimental measurement of select combustion properties of POSF 4658, and the POSF 4658 surrogate. (1)A variable pressure flow reactor has been used to chart the chemical reactivity of stoichiometric mixtures of POSF 4658/O{sub 2}/N{sub 2} and POSF 4658 surrogate/O{sub 2}/N{sub 2} at 12.5 atm and 500-1000 K, fixing the carbon content at 0.3% for both mixtures. (2)The high temperature chemical reactivity and chemical kinetic-molecular diffusion coupling of POSF 4658 and POSF 4658 surrogate have been evaluated by measurement of the strained extinction limit of diffusion flames. (3)The autoignition behavior of POSF 4658 and POSF 4658 surrogate has been measured with a shock tube at 674-1222 K and with a rapid compression machine at 645-714 K for stoichiometric mixtures of fuel in air at pressures close to 20 atm. The flow reactor study shows that the character and extent of chemical reactivity of both fuels at low temperature (500-675 K) and high temperature (900 K+) are extremely similar. Slight differences in the transition from the end of the negative temperature coefficient regime to hot ignition are observed. The diffusion flame strained extinction limits of the fuels are observed to be indistinguishable when compared on a molar basis. Ignition delay measurements also show that POSF 4658 exhibits NTC behavior. Moreover, the ignition delays of both fuels are also extremely similar over the temperature range studied in both shock tube and rapid compression machine experiments. A chemical kinetic model is constructed and utilized to interpret the experimental observations and provides a rationale as to why the real fuel and surrogate fuel exhibit such similar reactivity. (author)

Dooley, Stephen; Won, Sang Hee; Chaos, Marcos; Heyne, Joshua; Ju, Yiguang; Dryer, Frederick L. [Department of Mechanical and Aerospace Engineering, Princeton University, Princeton, NJ 08544 (United States); Kumar, Kamal; Sung, Chih-Jen [School of Engineering, University of Connecticut, Storrs, CT (United States); Wang, Haowei; Oehlschlaeger, Matthew A. [Department of Mechanical, Aerospace, and Nuclear Engineering, Rensselaer Polytechnic Institute, Troy, NY (United States); Santoro, Robert J.; Litzinger, Thomas A. [Propulsion Engineering Research Center, The Pennsylvania State University, University Park, PA (United States)

2010-12-15

168

Combustion studies of coal derived solid fuels by thermogravimetric analysis. III. Correlation between burnout temperature and carbon combustion efficiency  

USGS Publications Warehouse

Burning profiles of 35-53 ??m size fractions of an Illinois coal and three partially devolatilized coals prepared from the original coal were obtained using a thermogravimetric analyzer. The burning profile burnout temperatures were higher for lower volatile fuels and correlated well with carbon combustion efficiencies of the fuels when burned in a laboratory-scale laminar flow reactor. Fuels with higher burnout temperatures had lower carbon combustion efficiencies under various time-temperature conditions in the laboratory-scale reactor. ?? 1990.

Rostam-Abadi, M.; DeBarr, J.A.; Chen, W.T.

1990-01-01

169

The Implications of Fossil Fuel Combustion for Climate Change  

Microsoft Academic Search

Emissions from fossil fuel combustion alter the composition of the atmosphere and have been touted as a major cause of climate change. The amount of CO2 in the atmosphere, for example, has increased by more than 30% since pre-industrial times. Average global surface temperature has increased by approximately 0.6 ▒ 0.2 ║C since the late 19th Century, and surface temperature

Kristy E. Ross; Stuart J. Piketh

170

Fireside Corrosion in Oxy-fuel Combustion of Coal  

SciTech Connect

Oxy-fuel combustion is burning a fuel in oxygen rather than air. The low nitrogen flue gas that results is relatively easy to capture CO{sub 2} from for reuse or sequestration. Corrosion issues associated with the environment change (replacement of much of the N{sub 2} with CO{sub 2} and higher sulfur levels) from air- to oxy-firing were examined. Alloys studied included model Fe-Cr alloys and commercial ferritic steels, austenitic steels, and nickel base superalloys. The corrosion behavior is described in terms of corrosion rates, scale morphologies, and scale/ash interactions for the different environmental conditions.

G. R. Holcomb; J. Tylczak; G. H. Meier; B. Lutz; K. Jung; N. Mu; N. M. Yanar; F. S. Pettit; J. Zhu; A. Wise; D. Laughlin; S. Sridhar

2012-05-20

171

Prediction of Agglomeration, Fouling, and Corrosion Tendency of Fuels in CFB Co-Combustion  

NASA Astrophysics Data System (ADS)

Prediction of agglomeration, fouling, and corrosion tendency of fuels is essential to the design of any CFB boiler. During the years, tools have been successfully developed at Foster Wheeler to help with such predictions for the most commercial fuels. However, changes in fuel market and the ever-growing demand for co-combustion capabilities pose a continuous need for development. This paper presents results from recently upgraded models used at Foster Wheeler to predict agglomeration, fouling, and corrosion tendency of a variety of fuels and mixtures. The models, subject of this paper, are semi-empirical computer tools that combine the theoretical basics of agglomeration/fouling/corrosion phenomena with empirical correlations. Correlations are derived from Foster Wheeler's experience in fluidized beds, including nearly 10,000 fuel samples and over 1,000 tests in about 150 CFB units. In these models, fuels are evaluated based on their classification, their chemical and physical properties by standard analyses (proximate, ultimate, fuel ash composition, etc.;.) alongside with Foster Wheeler own characterization methods. Mixtures are then evaluated taking into account the component fuels. This paper presents the predictive capabilities of the agglomeration/fouling/corrosion probability models for selected fuels and mixtures fired in full-scale. The selected fuels include coals and different types of biomass. The models are capable to predict the behavior of most fuels and mixtures, but also offer possibilities for further improvements.

BariÜ?, Vesna; Zabetta, Edgardo Coda; Sarkki, Juha

172

DOE Project 18546, AOP Task 1.1, Fuel Effects on Advanced Combustion Engines  

SciTech Connect

Research in 2011 was focused on diesel range fuels and diesel combustion and fuels evaluated in 2011 included a series of oxygenated biofuels fuels from University of Maine, oxygenated fuel compounds representing materials which could be made from sewage, oxygenated marine diesel fuels for low emissions, and a new series of FACE fuel surrogates and FACE fuels with detailed exhaust chemistry and particulate size measurements. Fuels obtained in late 2011, which will be evaluated in 2012, include a series of oil shale derived fuels from PNNL, green diesel fuel (hydrotreated vegetable oil) from UOP, University of Maine cellulosic biofuel (levulene), and pyrolysis derived fuels from UOP pyrolysis oil, upgraded at University of Georgia. We were able to demonstrate, through a project with University of Wisconsin, that a hybrid strategy for fuel surrogates provided both accurate and rapid CFD combustion modeling for diesel HCCI. In this strategy, high molecular weight compounds are used to more accurately represent physical processes and smaller molecular weight compounds are used for chemistry to speed chemical calculations. We conducted a small collaboration with sp3H, a French company developing an on-board fuel quality sensor based on near infrared analysis to determine how to use fuel property and chemistry information for engine control. We were able to show that selected outputs from the sensor correlated to both fuel properties and to engine performance. This collaboration leveraged our past statistical analysis work and further work will be done as opportunity permits. We conducted blending experiments to determine characteristics of ethanol blends based on the gasoline characteristics used for blending. Results indicate that much of the octane benefits gained by high level ethanol blending can be negated by use of low octane gasoline blend stocks, as allowed by ASTM D5798. This may limit ability to optimize engines for improved efficiency with ethanol fuels. Extensive data from current and previous years was leveraged into participation with several large proposal teams, as our fuels database covers a very wide range of conventional and emerging fuels and biofuels.

Bunting, Bruce G [ORNL; Bunce, Michael [ORNL

2012-01-01

173

Analytical fuel property effects--small combustors  

NASA Technical Reports Server (NTRS)

The consequences of using broad-property fuels in both conventional and advanced state-of-the-art small gas turbine combustors are assessed. Eight combustor concepts were selected for initial screening, of these, four final combustor concepts were chosen for further detailed analysis. These included the dual orifice injector baseline combustor (a current production 250-C30 engine combustor) two baseline airblast injected modifications, short and piloted prechamber combustors, and an advanced airblast injected, variable geometry air staged combustor. Final predictions employed the use of the STAC-I computer code. This quasi 2-D model includes real fuel properties, effects of injector type on atomization, detailed droplet dynamics, and multistep chemical kinetics. In general, fuel property effects on various combustor concepts can be classified as chemical or physical in nature. Predictions indicate that fuel chemistry has a significant effect on flame radiation, liner wall temperature, and smoke emission. Fuel physical properties that govern atomization quality and evaporation rates are predicted to affect ignition and lean-blowout limits, combustion efficiency, unburned hydrocarbon, and carbon monoxide emissions.

Sutton, R. D.; Troth, D. L.; Miles, G. A.

1984-01-01

174

Thermodynamic, transport, and flow properties of gaseous products resulting from combustion of methane-air-oxygen  

NASA Technical Reports Server (NTRS)

Results of calculations to determine thermodynamic, transport, and flow properties of combustion product gases are presented. The product gases are those resulting from combustion of methane-air-oxygen and methane-oxygen mixtures. The oxygen content of products resulting from the combustion of methane-air-oxygen mixtures was similiar to that of air; however, the oxygen contained in products of methane-oxygen combustion ranged from 20 percent by volume to zero for stoichiometric combustion. Calculations were made for products of reactant mixtures with fuel percentages, by mass, of 7.5 to 20. Results are presented for specific mixtures for a range of pressures varying from 0.0001 to 1,000 atm and for temperatures ranging from 200 to 3,800 K.

Klich, G. F.

1976-01-01

175

Effect of market fuel variation and cetane improvers on CAI combustion in a GDI engine  

E-print Network

There is continued interest in improving the fuel conversion efficiency of internal combustion engines and simultaneously reducing their emissions. One promising technology is that of Controlled Auto Ignition (CAI) combustion. ...

Cedrone, Kevin David

2010-01-01

176

Structural and magnetic properties of barium hexaferrite nanostructured particles prepared by the combustion method  

Microsoft Academic Search

The combustion method, a fast and simple way of preparing sub-micrometer sized particles from a solution of the corresponding metal nitrates and a reducing agent (ODH, TFTA) which is used as a fuel, was adapted to the synthesis of barium hexaferrite particles. Structural and magnetic properties were investigated by X-ray diffraction, transmission electronic microscopy, magnetic measurements and M÷ssbauer spectrometry on

S. Castro; M. Gayoso; J. Rivas; J. M. Greneche; J. Mira; C. RodrÝguez

1996-01-01

177

Combustion  

NASA Technical Reports Server (NTRS)

An overview of the emissions related research being conducted as part of the Fundamental Aeronautics Subsonics Fixed Wing Project is presented. The overview includes project metrics, milestones, and descriptions of major research areas. The overview also includes information on some of the emissions research being conducted under NASA Research Announcements. Objective: Development of comprehensive detailed and reduced kinetic mechanisms of jet fuels for chemically-reacting flow modeling. Scientific Challenges: 1) Developing experimental facilities capable of handling higher hydrocarbons and providing benchmark combustion data. 2) Determining and understanding ignition and combustion characteristics, such as laminar flame speeds, extinction stretch rates, and autoignition delays, of jet fuels and hydrocarbons relevant to jet surrogates. 3) Developing comprehensive kinetic models for jet fuels.

Bulzan, Dan

2007-01-01

178

Combustion characterization of beneficiated coal-based fuels. Quarterly report No. 5, May 1990--June 1990  

SciTech Connect

The objectives of this project include: (1) the development of an engineering data base which will provide detailed information on the properties of BCFs influencing combustion, ash deposition, ash erosion, particulate collection, and emissions; and (2) the application of this technical data base to predict the performance and economic impacts of firing the BCFs in various commercial boiler designs. The technical approach used to develop the technical data includes: bench-scale fuel property, conbustion, and ash deposition tests; pilot-scale combustion and ash effects tests; and full-scale combustion tests. Subcontractors to CE to perform parts of the test work are the Massachusetts Institute of Technology (MIT), Physical Sciences, Inc. Technology Company (PSIT) and the University of North Dakota Energy and Environmental Research Center (UNDEERC). Twenty fuels will be characterized during the three-year base program: three feed coals, fifteen BCFs, and two conventionally cleaned coals for the full-scale tests. Approximately nine BCFs will be in dry ultra-fine coal (DUC) form, and six BCFs will be in coal-water fuel (CWF) form. Additional BCFs would be characterized during optional project supplements.

Chow, O.K.; Nsakala, N.Y.

1990-08-01

179

Organic aerosol emission ratios from the laboratory combustion of biomass fuels  

NASA Astrophysics Data System (ADS)

aerosol (OA) emission ratios (ER) have been characterized for 67 burns during the second Fire Laboratory at Missoula Experiment. These fires involved 19 different species representing 6 major fuels, each of which forms an important contribution to the U.S. biomass burning inventory. Average normalized ?OA/?CO ratios show a high degree of variability, both between and within different fuel types and species, typically exceeding differen-ces between separate plumes in ambient measurements. This variability is strongly influenced by highly contrasting ?OA levels between burns and the increased partitioning of semivolatile organic compounds to the particle phase at high ?OA concentrations. No correlation across all fires was observed between ?OA/?CO and modified combustion efficiency (MCE), which acts as an indicator of the proportional contributions of flaming and smoldering combustion phases throughout each burn. However, a negative correlation exists with MCE for some coniferous species, most notably Douglas fir, for which there is also an influence from fuel moisture content. Changes in fire efficiency were also shown to dramatically alter emissions for fires with very similar initial conditions. Although the relationship with MCE is variable between species, there is greater consistency with the level of oxygenation in OA. The ratio of the m/z 44 fragment to total OA mass concentration (f44) as measured by aerosol mass spectrometer provides an indication of oxygenation as influenced by combustion processes at source, with ?OA/?CO decreasing with increasing f44 for all fuel types. Inconsistencies in the magnitude of the effects associated with each potential influence on ?OA/?CO emphasize the lack of a single dominant control on fire emissions, and a dependency on both fuel properties and combustion conditions.

Jolleys, Matthew D.; Coe, Hugh; McFiggans, Gordon; McMeeking, Gavin R.; Lee, Taehyoung; Kreidenweis, Sonia M.; Collett, Jeffrey L.; Sullivan, Amy P.

2014-11-01

180

FUEL FORMULATION EFFECTS ON DIESEL FUEL INJECTION, COMBUSTION, EMISSIONS AND EMISSION CONTROL  

SciTech Connect

This paper describes work under a U.S. DOE sponsored Ultra Clean Fuels project entitled ''Ultra Clean Fuels from Natural Gas,'' Cooperative Agreement No. DE-FC26-01NT41098. In this study we have examined the incremental benefits of moving from low sulfur diesel fuel and ultra low sulfur diesel fuel to an ultra clean fuel, Fischer-Tropsch diesel fuel produced from natural gas. Blending with biodiesel, B100, was also considered. The impact of fuel formulation on fuel injection timing, bulk modulus of compressibility, in-cylinder combustion processes, gaseous and particulate emissions, DPF regeneration temperature and urea-SCR NOx control has been examined. The primary test engine is a 5.9L Cummins ISB, which has been instrumented for in-cylinder combustion analysis and in-cylinder visualization with an engine videoscope. A single-cylinder engine has also been used to examine in detail the impacts of fuel formulation on injection timing in a pump-line-nozzle fueling system, to assist in the interpretation of results from the ISB engine.

Boehman, A; Alam, M; Song, J; Acharya, R; Szybist, J; Zello, V; Miller, K

2003-08-24

181

Analysis of Fuel Vaporization, Fuel-Air Mixing, and Combustion in Integrated Mixer-Flame Holders  

NASA Technical Reports Server (NTRS)

Requirements to limit pollutant emissions from the gas turbine engines for the future High-Speed Civil Transport (HSCT) have led to consideration of various low-emission combustor concepts. One such concept is the Integrated Mixer-Flame Holder (IMFH). This report describes a series of IMFH analyses performed with KIVA-II, a multi-dimensional CFD code for problems involving sprays, turbulence, and combustion. To meet the needs of this study, KIVA-II's boundary condition and chemistry treatments are modified. The study itself examines the relationships between fuel vaporization, fuel-air mixing, and combustion. Parameters being considered include: mixer tube diameter, mixer tube length, mixer tube geometry (converging-diverging versus straight walls), air inlet velocity, air inlet swirl angle, secondary air injection (dilution holes), fuel injection velocity, fuel injection angle, number of fuel injection ports, fuel spray cone angle, and fuel droplet size. Cases are run with and without combustion to examine the variations in fuel-air mixing and potential for flashback due to the above parameters. The degree of fuel-air mixing is judged by comparing average, minimum, and maximum fuel/air ratios at the exit of the mixer tube, while flame stability is monitored by following the location of the flame front as the solution progresses from ignition to steady state. Results indicate that fuel-air mixing can be enhanced by a variety of means, the best being a combination of air inlet swirl and a converging-diverging mixer tube geometry. With the IMFH configuration utilized in the present study, flashback becomes more common as the mixer tube diameter is increased and is instigated by disturbances associated with the dilution hole flow.

Deur, J. M.; Cline, M. C.

2004-01-01

182

On-Line Measurement of Heat of Combustion of Gaseous Hydrocarbon Fuel Mixtures  

NASA Technical Reports Server (NTRS)

A method for the on-line measurement of the heat of combustion of gaseous hydrocarbon fuel mixtures has been developed and tested. The method involves combustion of a test gas with a measured quantity of air to achieve a preset concentration of oxygen in the combustion products. This method involves using a controller which maintains the fuel (gas) volumetric flow rate at a level consistent with the desired oxygen concentration in the combustion products. The heat of combustion is determined form a known correlation with the fuel flow rate. An on-line computer accesses the fuel flow data and displays the heat of combustion measurement at desired time intervals. This technique appears to be especially applicable for measuring heats of combustion of hydrocarbon mixtures of unknown composition such as natural gas.

Sprinkle, Danny R.; Chaturvedi, Sushil K.; Kheireddine, Ali

1996-01-01

183

Experimental results with hydrogen fueled internal combustion engines  

NASA Technical Reports Server (NTRS)

The paper focuses on the most important experimental findings for hydrogen-fueled internal combustion engines, with particular reference to the application of these findings to the assessment of the potential of hydrogen engines. Emphasis is on the various tradeoffs that can be made, such as between maximum efficiency, maximum power, and minimum NO emissions. The various possibilities for induction and ignition are described. Some projections are made about areas in which hydrogen engines may find their initial application and about optimum ways to design such engines. It is shown that hydrogen-fueled reciprocal internal combustion engines offer important advantages with respect to thermal efficiency and exhaust emissions. Problems arising from preignition can suitably be avoided by restricting the fuel-air equivalence ratio to values below about 0.5. The direct cylinder injection appears to be a very attractive way to operate the engine, because it combines a wide range of possible power outputs with a high thermal efficiency and very low NO emissions at part loads.

De Boer, P. C. T.; Mclean, W. J.; Homan, H. S.

1975-01-01

184

Internal combustion engine in which compressed fuel mixture is combusted externally of the cylinders of the engine in a rotating combustion chamber  

Microsoft Academic Search

An internal combustion engine is described comprising a cylinder body having a pair of adjoining first and second cylinders, a reciprocable piston in each cylinder, first valve means for introducing a fuel mixture in the first cylinder, second valve means for discharge of exhaust gases from the second cylinder, a combustion chamber mounted adjacent the cylinder body for movement between

Staheli

1988-01-01

185

Optical and chemical characterization of aerosols emitted from coal, heavy and light fuel oil, and small-scale wood combustion.  

PubMed

Particle emissions affect radiative forcing in the atmosphere. Therefore, it is essential to know the physical and chemical characteristics of them. This work studied the chemical, physical, and optical characteristics of particle emissions from small-scale wood combustion, coal combustion of a heating and power plant, as well as heavy and light fuel oil combustion at a district heating station. Fine particle (PM1) emissions were the highest in wood combustion with a high fraction of absorbing material. The emissions were lowest from coal combustion mostly because of efficient cleaning techniques used at the power plant. The chemical composition of aerosols from coal and oil combustion included mostly ions and trace elements with a rather low fraction of absorbing material. The single scattering albedo and aerosol forcing efficiency showed that primary particles emitted from wood combustion and some cases of oil combustion would have a clear climate warming effect even over dark earth surfaces. Instead, coal combustion particle emissions had a cooling effect. Secondary processes in the atmosphere will further change the radiative properties of these emissions but are not considered in this study. PMID:24328080

Frey, Anna K; Saarnio, Karri; Lamberg, Heikki; Myllńri, Fanni; Karjalainen, Panu; Teinilń, Kimmo; Carbone, Samara; Tissari, Jarkko; Niemelń, Ville; Hńyrinen, Anna; Rautiainen, Jani; Kyt÷mńki, Jorma; Artaxo, Paulo; Virkkula, Aki; Pirjola, Liisa; R÷nkk÷, Topi; Keskinen, Jorma; Jokiniemi, Jorma; Hillamo, Risto

2014-01-01

186

High pressure combustion of liquid fuels. [alcohol and n-paraffin fuels  

NASA Technical Reports Server (NTRS)

Measurements were made of the burning rates and liquid surface temperatures for a number of alcohol and n-paraffin fuels under natural and forced convection conditions. Porous spheres ranging in size from 0.64-1.9 cm O.D. were emloyed to simulate the fuel droplets. The natural convection cold gas tests considered the combustion in air of methanol, ethanol, propanol-1, n-pentane, n-heptane, and n-decane droplets at pressures up to 78 atmospheres. The pressure levels of the natural convection tests were high enough so that near critical combustion was observed for methanol and ethanol vaporization rates and liquid surface temperature measurements were made of droplets burning in a simulated combustion chamber environment. Ambient oxygen molar concentrations included 13%, 9.5% and pure evaporation. Fuels used in the forced convection atmospheric tests included those listed above for the natural convection tests. The ambient gas temperature ranged from 600 to 1500 K and the Reynolds number varied from 30 to 300. The high pressure forced convection tests employed ethanol and n-heptane as fuels over a pressure range of one to 40 atmospheres. The ambient gas temperature was 1145 K for the two combustion cases and 1255 K for the evaporation case.

Canada, G. S.

1974-01-01

187

Radiative and combustion properties of nanoparticle-laden liquids  

NASA Astrophysics Data System (ADS)

Key processes in energy conversion systems are radiative transport and combustion. The general objective of this dissertation is to improve energy conversion efficiency by a fundamental investigation of how nanoparticle-laden liquid suspensions, generally termed nanofluids, can be used to either enhance radiative absorption in solar thermal energy systems, or to improve the combustion properties of liquid fuels. The present study theoretically investigates the feasibility of using a non-concentrating direct absorption solar collector (DAC) and compares its performance with that of a typical flat-plate collector. Here a nanofluid - a mixture of water and aluminum nanoparticles - is used as the absorbing medium. It was observed that the presence of nanoparticles increases the absorption of incident radiation by more than 9 times over that of pure water. Under similar operating conditions, the efficiency of a DAC using nanofluid as the working fluid is found to be up to 10 percent higher (on an absolute basis) than that of a flat-plate collector. This study also attempts to improve the ignition properties of diesel fuel by investigating the influence of adding aluminum and aluminum-oxide nanoparticles to diesel. As part of this study, droplet ignition experiments were carried out atop a heated hot plate over the range of 688 to 768 degrees centigrade. Different types of fuel mixtures were used; both particle size (15 nm and 50 nm) as well as the volume fraction (0, 0.1 and 0.5 percent) of nanoparticles added to diesel were varied. It was observed that the ignition probability for the fuel mixtures which contained nanoparticles was significantly higher than that of pure diesel. Finally, the concept of using solar energy for converting biomass into useful product-gases was explored. A molten salt mixture (containing nanoparticles) was used to absorb and transfer solar energy to the biomass. Under the highest amount of solar radiation (60 times the normal solar radiation) about 1.1 tons of biomass could be converted to useful product-gases every hour, consuming about 900 kW of sunlight at an overall efficiency of 8 percent.

Tyagi, Himanshu

188

Catalytic iron oxide for lime regeneration in carbonaceous fuel combustion  

DOEpatents

Lime utilization for sulfurous oxides absorption in fluidized combustion of carbonaceous fuels is improved by impregnation of porous lime particulates with iron oxide. The impregnation is achieved by spraying an aqueous solution of mixed iron sulfate and sulfite on the limestone before transfer to the fluidized bed combustor, whereby the iron compounds react with the limestone substrate to form iron oxide at the limestone surface. It is found that iron oxide present in the spent limestone acts as a catalyst to regenerate the spent limestone in a reducing environment. With only small quantities of iron oxide the calcium can be recycled at a significantly increased rate.

Shen, Ming-Shing (Rocky Point, NY); Yang, Ralph T. (Middle Island, NY)

1980-01-01

189

Effects of fuel and additives on combustion chamber deposits  

SciTech Connect

The effects of gasoline composition, as represented in typical regular and premium unleaded gasolines and fuel additives, on Combustion Chamber Deposits (CCD) were investigated in BMW and Ford tests. In addition, the influences of engine lubricant oil and ethanol oxygenate on CCD were examined in Ford 2.3L engine dynamometer tests. Also, additive effects of packages based on mineral oil fluidizers versus synthetic fluidizers were studied in several different engines for CCD. Finally, a new method for evaluating the effect of fluidizers on valve sticking is introduced. 6 refs., 16 figs., 14 tabs.

Jackson, M.M.; Pocinki, S.B.

1994-10-01

190

Kinetics of pyrolysis, combustion and gasification of three biomass fuels  

Microsoft Academic Search

The paper compares the microstructural properties and the intrinsic reactivity of pine seed shells, olive husk and wood chips upon pyrolysis, combustion and gasification (with CO2 and H2O). Such biomasses, all of interest in energy production, are quite different from one another in terms of O\\/C and H\\/C content, of porosimetric structure and of ash content.An extensive campaign of isothermal

Osvalda Senneca

2007-01-01

191

Coal-water slurry fuel internal combustion engine and method for operating same  

DOEpatents

An internal combustion engine fueled with a coal-water slurry is described. About 90 percent of the coal-water slurry charge utilized in the power cycle of the engine is directly injected into the main combustion chamber where it is ignited by a hot stream of combustion gases discharged from a pilot combustion chamber of a size less than about 10 percent of the total clearance volume of main combustion chamber with the piston at top dead center. The stream of hot combustion gases is provided by injecting less than about 10 percent of the total coal-water slurry charge into the pilot combustion chamber and using a portion of the air from the main combustion chamber that has been heated by the walls defining the pilot combustion chamber as the ignition source for the coal-water slurry injected into the pilot combustion chamber.

McMillian, Michael H. (Fairmont, WV)

1992-01-01

192

Implications of Low Particulate Matter Emissions on System Fuel Efficiency for High Efficiency Clean Combustion  

Microsoft Academic Search

Advanced diesel combustion regimes such as High Efficiency Clean Combustion (HECC) offer the benefits of reduced engine out NOX and particulate matter (PM) emissions. Lower PM emissions during advanced combustion reduce the demand on diesel particulate filters (DPFs) and can, thereby, reduce the fuel penalty associated with DPF regeneration. In this study, a SiC DPF was loaded and regenerated on

II Parks; James E; Vitaly Y Prikhodko

2009-01-01

193

Studies on the combustion efficiency of liquid fuel rockets with variable thrust  

Microsoft Academic Search

This article carries out studies on the stability characteristics of liquid fuel rocket engines within a relatively large range of variations. The research work was carried out centering around the speed and efficiency characteristics of combustion chambers. This article sets out the results of relevant experiments and theoretical calculations. From the angle of the combustion processes within combustion chambers, there

Li Xiaobin; Qizhi Chen; Yunqin Chen

1991-01-01

194

Applying Thermodynamics to Fossil Fuels: Heats of Combustion from Elemental Compositions.  

ERIC Educational Resources Information Center

Discussed are the calculations of heats of combustions of some selected fossil fuel compounds such as some foreign shale oils and United States coals. Heating values for coal- and petroleum-derived fuel oils are also presented. (HM)

Lloyd, William G.; Davenport, Derek A.

1980-01-01

195

Estimation of Fuel Savings by Recuperation of Furnace Exhausts to Preheat Combustion Air  

E-print Network

The recovery of waste energy in furnace exhaust gases is gaining in importance as fuel costs continue to escalate. Installation of a recuperator in the furnace exhaust stream to preheat the combustion air can result in considerable savings in fuel...

Rebello, W. J.; Kohnken, K. H.; Phipps, H. R., Jr.

1980-01-01

196

Fireside Corrosion in Oxy-fuel Combustion of Coal  

SciTech Connect

Oxy-fuel combustion is burning a fuel in oxygen rather than air for ease of capture of CO2 from for reuse or sequestration. Corrosion issues associated with the environment change (replacement of much of the N2 with CO2 and higher sulfur levels) from air- to oxy-firing were examined. Alloys studied included model FeľCr alloys and commercial ferritic steels, austenitic steels, and nickel base superalloys. The corrosion behavior is described in terms of corrosion rates, scale morphologies, and scale/ash interactions for the different environmental conditions. Evidence was found for a hreshold for severe attack between 10-4 and 10-3 atm of SO3 at 700║C.

Holcomb, Gordon R [National Energy Technology Laboratory; Tylczak, Joseph [National Energy Technology Laboratory; Meier, Gerald H [University of Pittsburgh; Lutz, Bradley [University of Pittsburgh; Jung, Keeyoung [Institute of Industrial Science and Technology, Korea; Mu, Nan; Yanar, Nazik M [University of Pittsburgh; Pettit, Frederick S [University of Pittsburgh; Zhu, Jingxi [Carnegie Mellon University; Wise, Adam [Carnegie Mellon University; Laughlin, David E. [Carnegie Mellon University; Sridhar, Seetharaman [Carnegie Mellon University

2013-11-25

197

Liquid fuel vaporizer and combustion chamber having an adjustable thermal conductor  

DOEpatents

The efficiency and effectiveness of apparatuses for vaporizing and combusting liquid fuel can be improved using thermal conductors. For example, an apparatus having a liquid fuel vaporizer and a combustion chamber can be characterized by a thermal conductor that conducts heat from the combustion chamber to the vaporizer. The thermal conductor can be a movable member positioned at an insertion depth within the combustion chamber that corresponds to a rate of heat conduction from the combustion chamber to the vaporizer. The rate of heat conduction can, therefore, be adjusted by positioning the movable member at a different insertion depth.

Powell, Michael R; Whyatt, Greg A; Howe, Daniel T; Fountain, Matthew S

2014-03-04

198

Aerodynamic properties of turbulent combustion fields  

NASA Technical Reports Server (NTRS)

Flow fields involving turbulent flames in premixed gases under a variety of conditions are modeled by the use of a numerical technique based on the random vortex method to solve the Navier-Stokes equations and a flame propagation algorithm to trace the motion of the front and implement the Huygens principle, both due to Chorin. A successive over-relaxation hybrid method is applied to solve the Euler equation for flows in an arbitrarily shaped domain. The method of images, conformal transformation, and the integral-equation technique are also used to treat flows in special cases, according to their particular requirements. Salient features of turbulent flame propagation in premixed gases are interpreted by relating them to the aerodynamic properties of the flow field. Included among them is the well-known cellular structure of flames stabilized by bluff bodies, as well as the formation of the characteristic tulip shape of flames propagating in ducts. In its rudimentary form, the mechanism of propagation of a turbulent flame is shown to consist of: (1) rotary motion of eddies at the flame front, (2) self-advancement of the front at an appropriate normal burning speed, and (3) dynamic effects of expansion due to exothermicity of the combustion reaction. An idealized model is used to illustrate these fundamental mechanisms and to investigate basic aerodynamic features of flames in premixed gases. The case of a confined flame stabilized behind a rearward-facing step is given particular care and attention. Solutions are shown to be in satisfactory agreement with experimental results, especially with respect to global properties such as the average velocity profiles and reattachment length.

Hsiao, C. C.; Oppenheim, A. K.

1985-01-01

199

The use of petroleum coke as fuel in chemical-looping combustion  

Microsoft Academic Search

Chemical-looping combustion is a novel technique used for CO2 separation that previously has been demonstrated for gaseous fuel. This work demonstrates the feasibility of using solid fuel (petroleum coke) in chemical-looping combustion (CLC). Here, the reaction between the oxygen carrier and solid fuel occurs via the gasification intermediates, primarily CO and H2. A laboratory fluidized-bed reactor system for solid fuel,

Henrik Leion; Tobias Mattisson; Anders Lyngfelt

2007-01-01

200

Combustion of liquid fuel droplets in supercritical conditions  

NASA Technical Reports Server (NTRS)

A comprehensive analysis of liquid-fuel droplet combustion in both sub- and super-critical environments has been conducted. The formulation is based on the complete conservation equations for both gas and liquid phases, and accommodates finite-rate chemical kinetics and a full treatment of liquid-vapor phase equilibrium at the droplet surface. The governing equations and the associated interface boundary conditions are solved numerically using a fully coupled, implicit scheme with the dual time-stepping integration technique. The model is capable of treating the entire droplet history, including the transition from the subcritical to the supercritical state. As a specific example, the combustion of n-pentane fuel droplets in air is studied for pressures of 5-140 atm. Results indicate that the ambient gas pressure exerts significant control of droplet gasification and burning processes through its influences on the fluid transport, gas/liquid interface thermodynamics, and chemical reactions. The droplet gasification rate increases progressively with pressure. However, the data for the overall burnout time exhibits a significant variation near the critical burning pressure, mainly as a result of reduced mass-diffusion rate and latent heat of vaporization with increased pressure. The influence of droplet size on the burning characteristics is also noted.

Shuen, J. S.; Yang, Vigor

1991-01-01

201

Thermogravimetric investigation on the degradation properties and combustion performance of bio-oils.  

PubMed

The degradation properties and combustion performance of raw bio-oil, aged bio-oil, and bio-oil from torrefied wood were investigated through thermogravimetric analysis. A three-stage process was observed for the degradation of bio-oils, including devolatilization of the aqueous fraction and light compounds, transition of the heavy faction to solid, and combustion of carbonaceous residues. Pyrolysis kinetics parameters were calculated via the reaction order model and 3D-diffusion model, and combustion indexes were used to qualitatively evaluate the thermal profiles of tested bio-oils for comparison with commercial oils such as fuel oils. It was found that aged bio-oil was more thermally instable and produced more combustion-detrimental carbonaceous solid. Raw bio-oil and bio-oil from torrefied wood had comparable combustion performance to fuel oils. It was considered that bio-oil has a potential to be mixed with or totally replace the fuel oils in boilers. PMID:24300845

Ren, Xueyong; Meng, Jiajia; Moore, Andrew M; Chang, Jianmin; Gou, Jinsheng; Park, Sunkyu

2014-01-01

202

Low NO/x/ combustion systems for burning heavy residual fuels and high-fuel-bound nitrogen fuels  

NASA Technical Reports Server (NTRS)

Design concepts are presented for lean-lean and staged rich-lean combustors. The combustors are designed for the dry reduction of thermal NO(x), control of NO(x) from fuels containing high levels of organic nitrogen, and control of smoke from low hydrogen content fuels. The combustor concepts are tested with a wide variety of fuels including a middle distillate, a petroleum based heavy residual, a coal derived synthetic, and ratios of blends of these fuels. The configurations of the lean-lean and rich-lean combustion systems are provided along with a description of the test rig and test procedure.

White, D. J.; Batakis, A.; Lecren, R. T.; Yacobucci, H. G.

1981-01-01

203

A kinetic-empirical model for particle size distribution evolution during pulverised fuel combustion  

Microsoft Academic Search

Particle size is an essential parameter in pulverised fuel (PF) combustion as many of the problems or further areas of development in these systems are strongly influenced by the fuel and ash size distribution. This is particularly true for dynamic processes like pollutant formation, corrosion, erosion, slagging and fouling and the related decrease of the combustion and boiler efficiency. The

Kalpit V. Shah; Mariusz K. Cieplik; Christine I. Betrand; Willem L. van de Kamp; Hari B. Vuthaluru

2010-01-01

204

THE INFLUENCE OF CARBON BURNOUT ON SUBMICRON PARTICLE FORMATION FROM EMULSIFIED FUEL OIL COMBUSTION  

EPA Science Inventory

The paper gives results of an examination of particle behavior and particle size distributions from the combustion of different fuel oils and emulsified fuels in three experimental combusators. Results indicate that improved carbon (C) burnout from fule oil combustion, either by...

205

Method of treating exhaust gases from a methanol fueled internal combustion engine  

Microsoft Academic Search

A method of oxidizing that portion of a methanol fuel which has not been burned in an internal combustion engine is disclosed. Briefly, the method includes the following steps. A methanol fuel is burned in an internal combustion engine thereby to produce exhaust gases which contain unburned methanol. The exhaust gases containing the unburned methanol are passed over a catalyst

Yao

1981-01-01

206

CHARACTERIZATION OF EMISSIONS FROM THE COMBUSTION OF WOOD AND ALTERNATIVE FUELS IN A RESIDENTIAL WOODSTOVE  

EPA Science Inventory

The report gives results of a comparison of emissions from the combustion of alternative fuels to those from wood in a residential woodstove, and of a study of the effects of woodstove operating parameters on combustion emissions. Overall, oak wood is the best fuel tested, consid...

207

Fuel combustion exhibiting low NO{sub x} and CO levels  

DOEpatents

Method and apparatus are disclosed for safely combusting a fuel in such a manner that very low levels of NO{sub x} and CO are produced. The apparatus comprises an inlet line containing a fuel and an inlet line containing an oxidant. Coupled to the fuel line and to the oxidant line is a mixing means for thoroughly mixing the fuel and the oxidant without combusting them. Coupled to the mixing means is a means for injecting the mixed fuel and oxidant, in the form of a large-scale fluid dynamic structure, into a combustion region. Coupled to the combustion region is a means for producing a periodic flow field within the combustion region to mix the fuel and the oxidant with ambient gases in order to lower the temperature of combustion. The means for producing a periodic flow field can be a pulse combustor, a rotating band, or a rotating cylinder within an acoustic chamber positioned upstream or downstream of the region of combustion. The mixing means can be a one-way flapper valve; a rotating cylinder; a rotating band having slots that expose open ends of said fuel inlet line and said oxidant inlet line simultaneously; or a set of coaxial fuel annuli and oxidizer annuli. The means for producing a periodic flow field may or may not be in communication with an acoustic resonance. When employed, the acoustic resonance may be upstream or downstream of the region of combustion. 14 figs.

Keller, J.O.; Bramlette, T.T.; Barr, P.K.

1996-07-30

208

Combustion tests of a turbine simulator burning low Btu fuel from a fixed bed gasifier  

Microsoft Academic Search

One of the most efficient and environmentally compatible coal fueled power generation technologies is the integrated gasification combined cycle (IGCC) concept. Commercialization of the IGCC\\/HGCU concept requires successful development of combustion systems for high temperature low Btu fuel in gas turbines. Toward this goal, a turbine combustion system simulator has been designed, constructed, and fired with high temperature low Btu

C. S. Cook; N. Abuaf; A. S. Feitelberg; S. L. Hung; D. J. Najewicz; M. S. Samuels

1993-01-01

209

Fluidized bed combustion of alternative solid fuels; status, successes and problems of the technology  

Microsoft Academic Search

Fluidized bed combustion can be used for energy production or incineration for almost any material containing carbon, hydrogen and sulphur in a combustible form, whether it be in the form of a solid, liquid, slurry or gas. The technology's fuel flexibility arises from the fact that the fuel is present in the combustor at a low level and is burnt

E. J Anthony

1995-01-01

210

Thermodynamic and transport combustion properties of hydrocarbons with air. Part 1: Properties in SI units  

NASA Technical Reports Server (NTRS)

Thermodynamic and transport combustion properties were calculated for a wide range of conditions for the reaction of hydrocarbons with air. Three hydrogen-carbon atom ratios (H/C = 1.7, 2.0, 2.1) were selected to represent the range of aircraft fuels. For each of these H/C ratios, combustion properties were calculated for the following conditions: Equivalence ratio: 0, 0.25, 0.5, 0.75, 1.0, 1.25 Water - dry air mass ratio: 0, 0.03 Pressure, kPa: 1.01325, 10.1325, 101.325, 1013.25, 5066.25 (or in atm: 0.01, 0.1, 1, 10, 50) Temperature, K: every 10 degrees from 200 to 900 K; every 50 degrees from 900 to 3000 K Temperature, R: every 20 degrees from 360 to 1600 R; very 100 degrees from 1600 to 5400 R. The properties presented are composition, density, molecular weight, enthalphy, entropy, specific heat at constant pressure, volume derivatives, isentropic exponent, velocity of sound, viscosity, thermal conductivity, and Prandtl number. Property tables are based on composites that were calculated by assuming both: (1) chemical equilibrium (for both homogeneous and heterogeneous phases) and (2) constant compositions for all temperatures. Properties in SI units are presented in this report for the Kelvin temperature schedules.

Gordon, S.

1982-01-01

211

Determination of the conversion degree of fuel bounded nitrogen compounds at the combustion of liquid fuels  

SciTech Connect

The NO-concentration in the fluegas of furnaces for liquid fuels is the sum of the thermal, prompt and fuel NO-formation. Most measures to reduce NO-emissions aim mainly on the decrease of the maximum temperature and therefore on the thermal NO-formation. Recently the fuel NO-formation has become more relevant due to the fact that for modern LowNOx combustion concepts 30 to 60% of the NO-emission result from the conversion of fuel-bounded nitrogen to NO. The reduction of the concentration of fuel-bounded nitrogen in fuels causes a high energy demand during the refining process and has not been realized yet because of economic items. Due to this reason this investigation provides fundamentals of the conversion degree of fuel-bounded nitrogen in technical flames. These fundamentals are useful to design new burner heads which can reduce the NO-emission due to the fuel NO-formation. Additionally the suitability of model fuels for a standardized judgment of the emissions in acceptance tests and for the mathematical modeling of the fuel NO-formation is discussed. In literature there are only a few results for conversion degrees of fuel-bounded nitrogen compounds. As well there is no satisfying analyzing technique for the determination of specific nitrogen compounds in liquid fuels. Therefore relevant material data for nitrous hydrocarbons which are in the boiling range of liquid fuels has been summarized. Additionally nitrogen compounds in liquid fuels were determined with a new analyzing method developed by Severin and David. Results will be presented which show the influence of the air ratio, the mass fraction of nitrogen, the basic fuel used and chosen nitrogen compound on the conversion degree in technical diffusion and premixed flames.

Lucka, K.; Koehne, H.

1998-07-01

212

Explosively Driven Combustion of Shock-Dispersed Fuels  

NASA Astrophysics Data System (ADS)

Since the eighties our working group has been studying classical blast effects in small-scale experiments using custom-made miniature charges of 0.2 g to 1.5 g PETN. However, in the recent years the interest has shifted towards the performance of non-ideal explosives and the importance of secondary reactions such as after-burning. Thus we have designed an additional charge type, called Shock-Dispersed Fuel (SDF) charge. It consists of a lightweight, small paper cylinder filled with about one gram of a flammable powder (e.g., flake aluminum) surrounding a spherical PETN booster of 0.5 g. We have tested the SDF charges in a number of different environments, realized as closed steel vessels of simple geometry (barometric bombs). Three of the bombs vary in volume (6.6 l, 21.2 l and 40.5 l), while their aspect ratio L/D is kept constant at about 1. Two further bombs are comparable to the smallest bomb in volume (6.3 l), but provide different aspect ratios: L/D = 4.6 and 12.5. In addition, we have also performed tests in a tunnel-model with an L/D = 37.5. Our basic goal is to assess the performance of the charges by means of the combustion-related pressure built-up. Thus we contrast experiments on SDF charges in air with tests in nitrogen, to inhibit combustion, and with tests on conventional charges. Experiments and theoretical estimates on the expected overpressure allow one to formulate various indicators for the observed combustion performance. For SDF charges these indicate that the combustion efficiency decreases not only with increasing volume of the barometric bomb, but also with increasing aspect ratio at constant volume. This bears importance to the performance of SDF charges in tunnel environments. The performance losses reflect -- at least in part -- geometry-specific constraints on the mixing between fuel and air.

Neuwald, Peter

2005-07-01

213

Biomedically relevant chemical and physical properties of coal combustion products.  

PubMed Central

The evaluation of the potential public and occupational health hazards of developing and existing combustion processes requires a detailed understanding of the physical and chemical properties of effluents available for human and environmental exposures. These processes produce complex mixtures of gases and aerosols which may interact synergistically or antagonistically with biological systems. Because of the physicochemical complexity of the effluents, the biomedically relevant properties of these materials must be carefully assessed. Subsequent to release from combustion sources, environmental interactions further complicate assessment of the toxicity of combustion products. This report provides an overview of the biomedically relevant physical and chemical properties of coal fly ash. Coal fly ash is presented as a model complex mixture for health and safety evaluation of combustion processes. PMID:6337824

Fisher, G L

1983-01-01

214

Fluidized bed combustion of pelletized biomass and waste-derived fuels  

Microsoft Academic Search

The fluidized bed combustion of three pelletized biogenic fuels (sewage sludge, wood, and straw) has been investigated with a combination of experimental techniques. The fuels have been characterized from the standpoints of patterns and rates of fuel devolatilization and char burnout, extent of attrition and fragmentation, and their relevance to the fuel particle size distribution and the amount and size

R. Chirone; F. Scala; R. Solimene; P. Salatino; M. Urciuolo

2008-01-01

215

Public perception related to a hydrogen hybrid internal combustion engine transit bus demonstration and hydrogen fuel  

Microsoft Academic Search

Hydrogen has been widely considered as a potentially viable alternative to fossil fuels for use in transportation. In addition to price competitiveness with fossil fuels, a key to its adoption will be public perceptions of hydrogen technologies and hydrogen fuel. This paper examines public perceptions of riders of a hydrogen hybrid internal combustion engine bus and hydrogen as a fuel

Allister Hickson; Al Phillips; Gene Morales

2007-01-01

216

40 CFR 60.107a - Monitoring of emissions and operations for fuel gas combustion devices and flares.  

Code of Federal Regulations, 2014 CFR

...emissions and operations for fuel gas combustion devices and flares. 60.107a Section 60.107a...emissions and operations for fuel gas combustion devices and flares. (a) Fuel gas combustion devices subject to SO2 or H2 S limit and...

2014-07-01

217

40 CFR 60.107a - Monitoring of emissions and operations for fuel gas combustion devices and flares.  

Code of Federal Regulations, 2013 CFR

...emissions and operations for fuel gas combustion devices and flares. 60.107a Section 60.107a...emissions and operations for fuel gas combustion devices and flares. (a) Fuel gas combustion devices subject to SO2 or H2 S limit and...

2013-07-01

218

A new comprehensive reaction mechanism for combustion of hydrocarbon fuels  

SciTech Connect

A chemical kinetic model has been developed which describes pyrolysis, ignition and oxidation of many small hydrocarbon fuels over a wide range of experimental conditions. Fuels include carbon monoxide and hydrogen, methane and other alkane species up to n-butane, ethylene, propene, acetylene, and oxygenated species such as methanol, acetaldehyde and ethanol. Formation of some larger intermediate and product species including benzene, butadiene, large olefins, and cyclopentadiene has been treated in a semi-empirical manner. The reaction mechanism has been tested for conditions that do not involve transport and diffusional processes, including plug flow and stirred reactors, batch reactors and shock tubes. The present kinetic model and its validation differ from previous reaction mechanisms in two ways. First, in addition to conventional combustion data, experiments more commonly associated with chemical engineering problems such as oxidative coupling, oxidative pyrolysis and steam cracking are used to test the reaction mechanism, making it even more general than previous models. In addition, H atom abstraction and some other reaction rates, even for the smaller C{sub 2}, C{sub 3} and C{sub 4} species, are treated using approximations that facilitate future extensions to larger fuels in a convenient manner. Construction of the reaction mechanism and comparisons with experimental data illustrate the generality of the model.

Ranzi, E.; Sogaro, A.; Gaffuri, P.; Pennati, G. [Politecnico di Milano (Italy). Dipt. di Chimica Industriale e Ingegneria Chimica; Westbrook, C.K.; Pitz, W.J. [Lawrence Livermore National Lab., CA (United States)

1993-12-03

219

Properties of aircraft fuels and related materials. Final report, 8 Jul 85-30 Nov 90  

SciTech Connect

Topics of this technical study include: general analysis and characterization of conventional and experimental fuel properties which are unique and/or critical to engine performance and durability; special investigations; development and evaluation of new test methods; refinement of existing test methods; additive evaluation and quantification; investigation of fuel and material related field problems; advanced fuel requirements; and fuel system parameters for current and advanced engines. Specific topics include: lubricity, thermal stability, vapor pressure, thermal conductivity, high density fuels, corrosion inhibitors, and combustion.

Biddle, T.B.

1991-07-29

220

Combustion rates of chars from high-volatile fuels for FBC application  

SciTech Connect

The fluidized bed combustion of high volatile fuels is often associated with huge occurrence of comminution phenomena. These result into in-bed generation of substantial amounts of carbon fines which further undergo competitive processes of combustion and elutriation. The small size of carbon fines generated by comminution is such that their further combustion is largely controlled by the intrinsic kinetics of carbon oxidation, alone or in combination with intraparticle diffusion. The competition between fine combustion and elutriation strongly affects the efficiency of fixed carbon conversion and calls for thorough characterization of the combustion kinetics and of residence times of fines in a fluidized bed of coarse solids. In this paper a collection of intrinsic combustion kinetic and porosimetric data for chars from three high-volatile fuels suitable for FBC application is presented. Chars from a Refuse Derived Fuel (RDF), a Tyre Derived Fuel (TDF) and a biomass (Robinia Pseudoacacia) are obtained from devolatilization, in fluidized bed, of fuel samples. Thermogravimetric analysis, mercury porosimetry and helium pycnometry are used to characterize the reactivity and the pore structure of the chars. Combustion rates are characterized over a wide range of temperatures (320--850 C) and oxygen partial pressures, covering the entire range of interest in fluidized bed combustion. Analysis of thermogravimetric and porosimetric data is directed to obtaining the parameters (pre-exponential factors, reaction orders, activation energies, intraparticle diffusivities) of combustion kinetic submodels for application in fluidized bed combustor modeling.

Masi, S.; Salatino, P.; Senneca, O. [Univ. degli Studi di Napoli Federico II, Napoli (Italy)

1997-12-31

221

Predicting various biodiesel fuel properties  

Technology Transfer Automated Retrieval System (TEKTRAN)

Several essential fuel properties of biodiesel are largely determined by the properties of the fatty esters which are its main components. These include cetane number, kinematic viscosity, oxidative stability, and cold flow which are contained in almost all biodiesel standards but also other propert...

222

Combustion of refuse derived fuel in a fluidized bed  

SciTech Connect

Power generation from Refuse Derived Fuel (RDF) is an attractive utilization technology of municipal solid waste. To explain the behavior of RDF-fired fluidized bed incinerator, the commercial size RDF was continuously burnt in a 30 x 30 cm bubbling type fluidized-bed combustor. It was found that 12 kg/h of RDF feed rate was too high feed for this test unit and the Co level was higher than 500 ppm. However, 10 kg/h of RDF was a proper feed rate and the Co level was kept under 150 ppm. Secondary air injection and changing air ratio from the pipe grid were effective for the complete combustion of RDE. It was also found that HCl concentration in flue gas was controlled by the calcium component contained in RDF and its level was decreased with decreasing the combustor temperature.

Piao, Guilin; Aono, Shigeru; Mori, Shigekatsu; Deguchi, Seiichi; Fujima, Yukihisa [Nagoya Univ. (Japan)] [Nagoya Univ. (Japan); Kondoh, Motohiro; Yamaguchi, Masataka [Toyota Motor Corp. (Japan). Plant Engineering Dept.] [Toyota Motor Corp. (Japan). Plant Engineering Dept.

1998-12-31

223

Functionalized graphene sheet colloids for enhanced fuel/propellant combustion.  

PubMed

We have compared the combustion of the monopropellant nitromethane with that of nitromethane containing colloidal particles of functionalized graphene sheets or metal hydroxides. The linear steady-state burning rates of the monopropellant and colloidal suspensions were determined at room temperature, under a range of pressures (3.35-14.4 MPa) using argon as a pressurizing fluid. The ignition temperatures were lowered and burning rates increased for the colloidal suspensions compared to those of the liquid monopropellant alone, with the graphene sheet suspension having significantly greater burning rates (i.e., greater than 175%). The relative change in burning rate from neat nitromethane increased with increasing concentrations of fuel additives and decreased with increasing pressure until at high pressures no enhancement was found. PMID:19925013

Sabourin, Justin L; Dabbs, Daniel M; Yetter, Richard A; Dryer, Frederick L; Aksay, Ilhan A

2009-12-22

224

Corrosion of experimental superheater alloys in waste fuel combustion  

SciTech Connect

A number of experimental nickel base alloys have been evaluated regarding their resistance against high temperature corrosion in waste fuel combustion. Specimens were produced by hot extrusion of 50 kg ingots and exposed at 450 C and 490 C on cooled testing probes in the superheater section of a municipal solid waste (MSW) incineration plant. The effect on corrosion by different chromium, molybdenum and niobium concentrations were studied in terms of wall thickness reduction during test periods of up to 2,160 hours. Comparison was made with reference materials such as low alloyed pressure vessel steel (ASME SA213 T12), Alloy 28 (UNS N08028) and Alloy 625 (UNS N06625). The results indicated a positive effect in nickel base alloys on corrosion resistance especially of molybdenum but to some extent also of chromium. Nickel, niobium and iron showed no significant effect on corrosion resistance.

Nyloef, L. [AB Sandvik Steel, Sandviken (Sweden); Haeggblom, E. [Studsvik Material AB, Nykoeping (Sweden)

1997-08-01

225

Combustion Study of Stabilized Water-in-Diesel Fuel Emulsion  

Microsoft Academic Search

An experimental investigation has been carried out to produce a stable diesel\\/water emulsion fuel and use it in a diesel engine under different operating and design conditions. The emulsion stayed stable for up to 30% water in diesel for up to one week and 20% water in diesel for four weeks. The physical properties of the stable W\\/D emulsions in

M. Y. E. Selim; M. T. Ghannam

2009-01-01

226

Effect [of] co-combustion of sewage sludge and biomass on combustion behavior and emissions in pulverized fuel systems  

SciTech Connect

Biomass not only has a considerable potential as an additional fuel source but also shows a reasonable cost level in comparison to other renewable energies. The practicable fuel types are both residual material from forestry and agriculture, such as wood or straw, and especially cultivated reproducible feedstock such as Miscanthus Sinensis, whole cereal plants, poplars, or willows. Besides as single fuel, it is also considered to be sensible to utilize biomass in co-combustion in existing firing systems, such as pc-fired power stations. Biomass or sewage sludge utilized as additional fuel in coal combustion systems has consequences on combustion behavior, emissions, corrosion and residual matter. The effects of burning sewage sludge and agricultural residuals such as straw and manure as well as specially grown energy plants in combination with coal were studied in a 0.5 MW pulverized fuel test facility and a 20 kW electrically heated combustor. A major aspect of the investigations had been the required preparation and milling of the additional fuels. The investigations showed that in co-combustion of straw with coal, a grinding of 6 mm and finer is sufficient. The definitely coarser milling degree of biomass delays combustion and is observable by in-flame measurements. The investigations reveal that biomass addition has a positive effect on emissions. Since biomass in most cases contains considerably less sulphur than coal, an increasing biomass share in the thermal output makes the SO{sub 2} emissions decrease proportionally. In addition, SO{sub 2} can partly be captured in the ash by the alkaline-earth fractions of the biomass ash. As for sewage sludge, the emissions of SO{sub 2} correlate with the sulphur content of the fuel and, hence, rise with an increasing share of this biomass. Independently from the type, biomass shows a considerably stronger release of volatile matter. This latter fact may have a positive impact on NOx emissions when NOx-reducing techniques are applied. Within the framework of these investigations the following configurations were used: (1) unstaged combustion with preblending of coal and biomass, (2) air-staged combustion with preblending of coal and biomass, (3) reburning with biomass as reduction fuel, and (4) various burner configurations. The results show that the burner design and operation mode have a great influence on the NOx emissions of combined flames. Air staging and reburning are effective measures to reduce the NOx emissions of combined fuels. NOx emissions smaller than 300 mg/m at 6% O{sub 2} can be reached with all fuels.

Spliethoff, H.; Hein, K.R.G.

1999-07-01

227

Emission characteristics and combustion instabilities in an oxy-fuel swirl-stabilized combustor  

Microsoft Academic Search

This paper presents an experimental study on the emission characteristics and combustion instabilities of oxy-fuel combustions\\u000a in a swirl-stabilized combustor. Different oxygen concentrations (X\\u000a oxy=25%?45%, where X\\u000a oxy is oxygen concentration by volume), equivalence ratios (?=0.75?1.15) and combustion powers (CP=1.08?2.02 kW) were investigated in the oxy-fuel (CH4\\/CO2\\/O2) combustions, and reference cases (X\\u000a oxy=25%?35%, CH4\\/N2\\/O2 flames) were covered. The results show

Guo-neng Li; Hao Zhou; Ke-fa Cen

2008-01-01

228

Nitrogen chemistry during burnout in fuel-staged combustion  

SciTech Connect

A parametric study of the chemistry of the burnout zone in reburning has been performed in laboratory plug flow reactors in the temperature range 800--1,350 K. Inlet mole fractions of NO, NH{sub 3}, HCN, CO, and O{sub 2} were varied, together with different temperatures and residence times to simulate reaction conditions in practical systems. Under lean conditions, a minimum in NO emission exists as a function of temperature. Both HCN and NH{sub 3} can act as either NO reductants or as sources for NO by oxidation. Reactions and selectivities for HCN and NH{sub 3} are controlled by the radical pool produced by fuel (CO) oxidation. As increasing amounts of CO were added, temperatures for both ignition and the minimum in NO became lower. At 2% CO, 4% O{sub 2}, and 100 ms residence time, the minimum in NO was found at approximately 1,000 K. At low temperatures, significant amounts of N{sub 2}O were measured in the reactor outlet. This is attributed to N{sub 2}O formation by HCN/NO reactions and to the slow decomposition of N{sub 2}O at these temperatures. Large reductions in NO were seen under fuel-rich conditions and at high temperatures. The observed NO reduction was very much dependent on the inlet mole fraction of O{sub 2}. Detailed chemical kinetic modeling of the experiments showed reasonable predictions for overall fuel-lean conditions, but the model failed to predict experimental results under fuel-rich conditions. The present results provide guidelines for optimizing the conditions for the burnout process of reburning, as well as other processes for NO{sub x} reduction by staged combustion. The results also provide a test basis for verifying kinetic models for nitrogen chemistry at low temperatures (800--1,350 K).

Kristensen, P.G.; Glarborg, P.; Dam-Johansen, K. [Technical Univ. of Denmark, Lyngby (Denmark). Dept. of Chemical Engineering] [Technical Univ. of Denmark, Lyngby (Denmark). Dept. of Chemical Engineering

1996-11-01

229

Performance Evaluation and Optimization of Diesel Fuel Properties and Chemistry in an HCCI Engine  

SciTech Connect

The nine CRC fuels for advanced combustion engines (FACE fuels) have been evaluated in a simple, premixed HCCI engine under varying conditions of fuel rate, air-fuel ratio, and intake temperature. Engine performance was found to vary mainly as a function of combustion phasing as affected by fuel cetane and engine control variables. The data was modeled using statistical techniques involving eigenvector representation of the fuel properties and engine control variables, to define engine response and allow optimization across the fuels for best fuel efficiency. In general, the independent manipulation of intake temperature and air-fuel ratio provided some opportunity for improving combustion efficiency of a specific fuel beyond the direct effect of targeting the optimum combustion phasing of the engine (near 5 CAD ATDC). High cetane fuels suffer performance loss due to easier ignition, resulting in lower intake temperatures, which increase HC and CO emissions and result in the need for more advanced combustion phasing. The FACE fuels also varied in T90 temperature and % aromatics, independent of cetane number. T90 temperature was found to have an effect on engine performance when combined with high centane, but % aromatics did not, when evaluated independently of cetane and T90.

Bunting, Bruce G [ORNL] [ORNL; Eaton, Scott J [ORNL] [ORNL; Crawford, Robert W [Rincon Ranch Consulting] [Rincon Ranch Consulting

2009-01-01

230

Effect of fuel zinc content on toxicological responses of particulate matter from pellet combustion in vitro.  

PubMed

Significant amounts of transition metals such as zinc, cadmium and copper can become enriched in the fine particle fraction during biomass combustion with Zn being one of the most abundant transition metals in wood combustion. These metals may have an important role in the toxicological properties of particulate matter (PM). Indeed, many epidemiological studies have found associations between mortality and PM Zn content. The role of Zn toxicity on combustion PM was investigated. Pellets enriched with 170, 480 and 2300mgZn/kg of fuel were manufactured. Emission samples were generated using a pellet boiler and the four types of PM samples; native, Zn-low, Zn-medium and Zn-high were collected with an impactor from diluted flue gas. The RAW 264.7 macrophage cell line was exposed for 24h to different doses (15, 50,150 and 300?gml(-1)) of the emission samples to investigate their ability to cause cytotoxicity, to generate reactive oxygen species (ROS), to altering the cell cycle and to trigger genotoxicity as well as to promote inflammation. Zn enriched pellets combusted in a pellet boiler produced emission PM containing ZnO. Even the Zn-low sample caused extensive cell cycle arrest and there was massive cell death of RAW 264.7 macrophages at the two highest PM doses. Moreover, only the Zn-enriched emission samples induced a dose dependent ROS response in the exposed cells. Inflammatory responses were at a low level but macrophage inflammatory protein 2 reached a statistically significant level after exposure of RAW 264.7 macrophages to ZnO containing emission particles. ZnO content of the samples was associated with significant toxicity in almost all measured endpoints. Thus, ZnO may be a key component producing toxicological responses in the PM emissions from efficient wood combustion. Zn as well as the other transition metals, may contribute a significant amount to the ROS responses evoked by ambient PM. PMID:25553547

Uski, O; Jalava, P I; Happo, M S; Torvela, T; Leskinen, J; Mńki-Paakkanen, J; Tissari, J; Sippula, O; Lamberg, H; Jokiniemi, J; Hirvonen, M-R

2015-04-01

231

New mixture formation technology of direct fuel injection stratified combustion SI engine (OSKA)  

SciTech Connect

A new type of internal combustion engine has been developed. The new idea incorporates an impinging part in the central piston cavity. The fuel spray is injected against the impinging area, spreads and forms a fuel mixture. Since a comparatively rich fuel mixture, always stays around the impinging part and ignition is accomplished at the center of the rich fuel mixture, steady, instantaneous and high-speed combustion is possible. As the fuel mixture is always formed in the cavity, there is little fuel in the squish area. Therefore, it is possible to prevent end-gas knocking, and in spite of the use of spark ignition, to operate the engine at higher compression ratio than a conventional premixed SI engine. Experiments with methanol fuel showed that BMEP was 1.1MPa and the maximum brake thermal efficiency was 42%. The combustion noise was lower than that of diesel engine. Brief tests with gasoline showed a maximum brake thermal efficency of 36%.

Kato, S.; Onishi, S.

1987-01-01

232

Effect of air-staging on mercury speciation in pulverized fuel co-combustion: part 2  

SciTech Connect

The concerns regarding global warming and need for new energy resources brought the concept of biomass and waste as secondary fuels to the power industry. Mercury emissions in cases of cofiring of chicken manure, olive residue, and B-wood with a high volatile bituminous coal blend are studied in the first part of this paper. The use of secondary fuels significantly affects NOx emissions due to different types of nitrogen present in the fuel matrix. Air-staging is a proven in-furnace NOx reduction technology. The present work mainly involves bench scale studies to investigate the effect of air-staging on partitioning of mercury in pulverized fuel co-combustion. The combustion experiments are carried out in an entrained flow reactor at 1300{sup o}C with a 20%th share of secondary fuels. Elemental and total gaseous mercury from the reactor is measured on-line, and ash is analyzed for particulate mercury along with elemental and surface properties. Reducing the air stoichiometry in the primary zone of the combustor increases unburnt carbon which in turn reduces mercury emissions in the gas phase. Ash analysis shows the effect of surface area, particle size, and unburnt carbon on mercury capture. Calcium variation in the ash was observed due to formation of different slag in reducing and oxidizing conditions and might have affected the mercury capture in combination with the above parameters. A low iron concentration of ash does not seem to affect the capture of mercury. The results will help in predicting different forms of mercury emitted from the furnace at desired operating conditions which will eventually form the basis for the design of the control strategies for mercury emissions. 22 refs., 3 figs., 1 tab.

Shishir P. Sable; Wiebren de Jong; Ruud Meij; Hartmut Spliethoff [Delft University Technology, Delft (Netherlands). Section Energy Technology, Department of Process and Energy

2007-08-15

233

Computational Fluid Dynamics Modelling of Residual Fuel Oil Combustion in the Context of Marine Diesel Engines  

Microsoft Academic Search

A simplified model is presented for vaporization and combustion of heavy residual based fuel oil in high-pressure sprays, in the context of marine diesel engines. The fuel is considered as a mix of residual base and cutter stock. The model accounts for multiple fuel components as well as limited diffusion rates and thermal decomposition rates within droplets by the use

L Goldsworthy

2006-01-01

234

APPLICATION OF ADVANCED TECHNOLOGY FOR NOX CONTROL: ALTERNATE FUELS AND FLUIDIZED-BED COAL COMBUSTION  

EPA Science Inventory

The paper discusses the effect of alternate fuels and fluidized coal combustion in controlling the emission of nitrogen oxides (NOx). The current trend in energy use in the U.S. is toward greater use of coal and coal derived fuels, and on ensuring that these fuels are produced an...

235

Estimating particulate matter health impact related to the combustion of different fossil fuels  

E-print Network

Estimating particulate matter health impact related to the combustion of different fossil fuels generated a web map service that allows to access information on fuel dependent health effects due a simulation. Combined with a dedicated emission inventory PM2.5 maps specified by fuel type were generated

Paris-Sud XI, Universit├ę de

236

An Evaluation of some Health Risks of the Pollution from Fossil Fuel Combustion  

E-print Network

94-27 An Evaluation of some Health Risks of the Pollution from Fossil Fuel Combustion Guy Landrieu is proceeding to the implementation oF this methodology in France for the fossil fuel cycles (coal/ oil, natural an accounting framework for identifying and quantifying the extemal costs associated with fuel cycles. A general

Paris-Sud XI, Universit├ę de

237

Determining size of drops in fuel mixture of internal combustion engines  

NASA Technical Reports Server (NTRS)

In compressorless Diesel engines and in explosion engines using fuels with high boiling points it is difficult to effect a good combustion of the fuel mixture. This report presents different methods for calculating the size and uniformity of fuel droplets and mixtures.

Sauter, J

1926-01-01

238

Light absorption by primary particles from fossil-fuel combustion: Implications for radiative forcing  

NASA Astrophysics Data System (ADS)

Interactions of visible radiation with atmospheric aerosols are important to the heat balance of the Earth. Accurate emission inventories of particles from combustion are required to predict anthropogenically-induced changes in the radiative balance. I present measurements of the optical properties of particles from several types of combustion and compare them with assumptions used in previous emission inventories. Emissions from an indirect-injection diesel engine were similar to expected values. However, a second engine with a direct-injection scheme emitted about 100 times the expected amount of both mass and light absorption because of a poor injection pattern. Total emissions from vehicles depend critically on the number of such "catastrophic" units in operation. Absorption emitted from a low-technology industrial lignite-burning furnace was about 20 times lower than previous estimates; the emitted particles contained partially aromatized carbon. Burning bituminous coal in a Chinese-style domestic combustor yielded significant light absorption, similar to published emission factors. Combustion of both coal briquettes obtained from China and lignite resulted in very low light absorption because tar release from these fuels was low. Combining the measurement and modeling results with an extensive literature survey, I estimated central, low and high values of emission factors for different fuels and combustion sectors. I then calculated a global emission inventory of light-absorbing carbon from fossil-fuel combustion. The total emission of light-absorbing carbon for 1994 is 3.7 Tg, about half the magnitude of previously published emission inventories. The upper and lower uncertainty boundaries are 0.8 and 44 Tg year--1. The largest sources of uncertainty are emission characteristics for residential coal and the existing fraction of "catastrophic" units in operation. Emission inventories for organic carbon (central value of 5.1 Tg year--1, with a range of 0.5-42 Tg year--1) and for primary particles (3 x 1028 year--1) are also presented. Radiative forcing by light-absorbing particles on a global-average basis is small, but regional effects are significant. In regions with high area-specific emissions, the central estimate of top-of-atmosphere forcing is about +0.7 W m--2, and the upper bound is around +4.0 W m --2.

Bond, Tami Christine

239

Analytical fuel property effects: Small combustors  

NASA Technical Reports Server (NTRS)

The study performed in Phase 1 of this program applies only to a T700/CT7 engine family type combustor functioning in the engine as defined and does not necessarily apply to other cycles or combustors of differing stoichiometry. The study was not extended to any of the fuel delivery accessories such as pumps or control systems, nor was there any investigation of potential systems problems which might arise as a consequence of abnormal properties such as density which might affect delivery schedules or aromatics content which might affect fuel system seals. The T700/CT7 engine is a front drive turboshaft or turboprop engine in the 1500-1800 shp (1120-1340 kW) class as currently configured with highpower core flows of about 10 lb/sec (4.5 kg/sec). It employs a straight-through annular combustion system less than 5 in. (12.5 cm) in length utilizing a machined ring film cooled construction and twelve low-pressure air blast fuel injectors. Commercial and Naval versions employ two 0.5 Joule capacitive discharge surface gap ignitors.

Cohen, J. D.

1984-01-01

240

Combustion characterization of beneficiated coal-based fuels. Quarterly report No. 7, October 1990--December 1990  

SciTech Connect

During the fourth quarter of 1990, the following technical progress was made: (1) Calculated the kinetic characteristics of chars from the combustion of microbubble flotation beneficiated products; (2) continued drop tube combustion tests of the spherical oil agglomeration beneficiated products; (3) analyzed the data from three (MIT) pilot-scale combustion tests of the Upper Freeport feed coal; and (4) continued analyses of the data from the CE pilot-scale tests of nine fuels.

Hargrove, M.J.; Chow, O.K.; Nsakala, N.Y.

1991-02-01

241

Diffusion combustion of a liquid fuel film on a metal substrate  

Microsoft Academic Search

Diffusion combustion of a film of a liquid fuel (n-undecane andn-butanol) deposited on the surface of a thin metal substrate is studied experimentally and theoretically. The experimental\\u000a data obtained show that the mechanism determining the heating and evaporation of the combustible liquid is the heat transfer\\u000a from the region of combustion products to the heating zone due to the high

I. G. Namyatov; S. S. Minaev; V. S. Babkin; V. A. Bunev; A. A. Korzhavin

2000-01-01

242

Pressure-coupled vaporization and combustion responses of liquid-fuel droplets in high-pressure environments  

NASA Technical Reports Server (NTRS)

The dynamic responses of liquid-fuel droplet vaporization and combustion to ambient pressure oscillations are examined. The analysis is based on the complete sets of conservation equations for both gas and liquid phases, and accommodates detailed treatments of finite-rate chemical kinetics and variable properties. With a full account of thermodynamic phase equilibrium at the droplet surface, the model enables a systematic examination of the effects of ambient flow conditions on the droplet behavior. The responses of hydrocarbon fuel droplets in both sub- and super-critical environments are investigated. Results indicate that the droplet gasification and burning mechanisms depend greatly on the ambient pressure. In particular, a rapid enlargement of the vaporization and combustion responses occurs when the droplet surface reaches its critical point, mainly due to the strong variations of latent heat of vaporization and thermophysical properties at the critical state.

Yang, Vigor; Shuen, J. S.; Hsiao, C. C.

1991-01-01

243

Advanced fuel system technology for utilizing broadened property aircraft fuels  

NASA Technical Reports Server (NTRS)

Factors which will determine the future supply and cost of aviation turbine fuels are discussed. The most significant fuel properties of volatility, fluidity, composition, and thermal stability are discussed along with the boiling ranges of gasoline, naphtha jet fuels, kerosene, and diesel oil. Tests were made to simulate the low temperature of an aircraft fuel tank to determine fuel tank temperatures for a 9100-km flight with and without fuel heating; the effect of N content in oil-shale derived fuels on the Jet Fuel Thermal Oxidation Tester breakpoint temperature was measured. Finally, compatibility of non-metallic gaskets, sealants, and coatings with increased aromatic content jet fuels was examined.

Reck, G. M.

1980-01-01

244

Development of high temperature air combustion technology in pulverized fossil fuel fired boilers  

Microsoft Academic Search

High temperature air combustion (HTAC) is a promising technology for energy saving, flame stability enhancement and NOx emission reduction. In a conventional HTAC system, the combustion air is highly preheated by using the recuperative or regenerative heat exchangers. However, such a preheating process is difficult to implement for pulverized fossil fuel fired boilers. In this paper, an alternative approach is

Hai Zhang; Guangxi Yue; Junfu Lu; Zhen Jia; Jiangxiong Mao; Toshiro Fujimori; Toshiyuki Suko; Takashi Kiga

2007-01-01

245

FINE PARTICLE EMISSIONS FROM RESIDUAL FUEL OIL COMBUSTION: CHARACTERIZATION AND MECHANISMS OF FORMATION  

EPA Science Inventory

The paper gives results of a comparison of the characteristics of particulate matter (PM) emitted from residual fuel oil combustion in two types of combustion equipment. A small commercial 732-kW fire-tube boiler yielded a weakly bi-modal particulate size distribution (PSD) with...

246

FINE PARTICLE EMISSIONS FROM RESIDUAL FUEL OIL COMBUSTION: CHARACTERIZATION AND MECHANISMS OF FORMATION  

EPA Science Inventory

The paper gives results of a comparison of the characteristics of particulate matter (PM) emitted from residual fuel oil combustion in two types of combustion equipment. A small commercial 732-kW-rated fire-tube boiler yielded a weakly bimodal PM size distribution (PSD) with over...

247

Chemical kinetic modeling of oxy-fuel combustion of sour gas for enhanced oil recovery  

E-print Network

Oxy-fuel combustion of sour gas, a mixture of natural gas (primarily methane (CH 4 )), carbon dioxide (CO 2 ), and hydrogen sulfide (H 2 S), could enable the utilization of large natural gas resources, especially when ...

Bongartz, Dominik

2014-01-01

248

Solid Fuel Delivery System Developed for Combustion Testing on the International Space Station  

NASA Technical Reports Server (NTRS)

NASA initiated Bioastronautics and Human Research Initiatives in 2001 and 2003, respectively, to enhance the safety and performance of humans in space. The Flow Enclosure Accommodating Novel Investigations in Combustion of Solids (FEANICS) is a multiuser facility being built at the NASA Glenn Research Center to advance these initiatives by studying fire safety and the combustion of solid fuels in the microgravity environment of the International Space Station (ISS). One of the challenges for the FEANICS team was to build a system that allowed for several consecutive combustion tests to be performed with minimal astronaut crew interaction. FEANICS developed a fuel carousel that contains a various number of fuel samples, depending on the fuel width, and introduces them one at a time into a flow tunnel in which the combustion testing takes place. This approach will allow the science team to run the experiments from the ground, while only requiring the crew to change out carousels after several tests have been completed.

Frate, David T.

2004-01-01

249

Hydrocarbon-fueled internal combustion engines: "the worst form of vehicle propulsion... except for all the other forms"  

E-print Network

Hydrocarbon-fueled internal combustion engines: "the worst form of vehicle propulsion... except of Southern California, Los Angeles, CA 90089-1453 Introduction Hydrocarbon-fueled internal combustion engines system paradigm are discussed. First a definition of an internal combustion engine is needed

250

Systematic assessment of combustion characteristics of biofuels and emulsions with water for use as diesel engine fuels  

Microsoft Academic Search

Measurements of the combustion performance of biofuel oils, blends with diesel fuel and emulsions with water have been made, using a variety of experimental techniques. Photographic examination of single droplets demonstrated similar burning rates to diesel fuel. High speed records revealed the explosive combustion of oil-water emulsion droplets. Spray-flame photography showed up the poor combustion efficiency at atmospheric pressure, of

Roy J. Crookes; Fariborz Kiannejad; Marouan A. A. Nazha

1997-01-01

251

Combustion of a substitution fuel made of cardboard and polyethylene: influence of the mix characteristicsŚexperimental approach  

Microsoft Academic Search

This article presents an experimental study of the combustion of substitution fuels elaborated from compressed mixes of cardboard and polyethylene (PE). These components are representative of two classical classes of waste materials: materials derived from wood and plastics. The combustion of these fuels has been experimentally characterized in terms of combustion rate, and quantity of PolyAromatic Hydrocarbons (PAH) pollutants emitted.

S. Salvador; M. Quintard; C. David

2004-01-01

252

Fuel combustion exhibiting low NO.sub.x and CO levels  

DOEpatents

Method and apparatus for safely combusting a fuel in such manner that very low levels of NO.sub.x and CO are produced. The apparatus comprises an inlet line (12) containing a fuel and an inlet line (18) containing an oxidant. Coupled to the fuel line (12) and to the oxidant line (18) is a mixing means (11,29,33,40) for thoroughly mixing the fuel and the oxidant without combusting them. Coupled to the mixing means (11,29,33,40) is a means for injecting the mixed fuel and oxidant, in the form of a large-scale fluid dynamic structure (8), into a combustion region (2). Coupled to the combustion region (2) is a means (1,29,33) for producing a periodic flow field within the combustion region (2) to mix the fuel and the oxidant with ambient gases in order to lower the temperature of combustion. The means for producing a periodic flow field can be a pulse combustor (1), a rotating band (29), or a rotating cylinder (33) within an acoustic chamber (32) positioned upstream or downstream of the region (2) of combustion. The mixing means can be a one-way flapper valve (11); a rotating cylinder (33); a rotating band (29) having slots (31) that expose open ends (20,21) of said fuel inlet line (12) and said oxidant inlet line (18) simultaneously; or a set of coaxial fuel annuli (43) and oxidizer annuli (42,44). The means for producing a periodic flow field (1, 29, 33) may or may not be in communication with an acoustic resonance. When employed, the acoustic resonance may be upstream or downstream of the region of combustion (2).

Keller, Jay O. (3534 Brunell Dr., Oakland, CA 94602); Bramlette, T. Tazwell (2105 Canyon Lakes Dr., San Ramon, CA 94583); Barr, Pamela K. (294 Joyce St., Livermore, CA 94550)

1996-01-01

253

Chemistry and radiation in oxy-fuel combustion: A computational fluid dynamics modeling study  

Microsoft Academic Search

In order to investigate the role of combustion chemistry and radiation heat transfer in oxy-fuel combustion modeling, a computational fluid dynamics (CFD) modeling study has been performed for two different oxy-fuel furnaces. One is a lab-scale 0.8MW oxy-natural gas flame furnace whose detailed in-flame measurement data are available; the other is a conventional 609MW utility boiler which is assumed to

Chungen Yin; Lasse A. Rosendahl; S°ren K. KŠr

2011-01-01

254

Comparative second-law analysis of internal combustion engine operation for methane, methanol, and dodecane fuels  

Microsoft Academic Search

A method for both combustion irreversibility and working medium availability computations in a high-speed, naturally-aspirated, four-stroke, internal combustion engine cylinder is presented. The results of the second-law analysis of engine operation with n-dodecane (n-C12H26) fuel are compared with the results of a similar analysis for cases where a light, gaseous (CH4) and an oxygenated (CH3OH) fuel is used. The rate

C. D Rakopoulos; D. C Kyritsis

2001-01-01

255

A cycle simulation of coal particle fueled reciprocating internal-combustion engines  

E-print Network

A CYCLE SIMULATION OF COAL PARTICLE FUELED RECIPROCATING INTERNAL-COMBUSTION ENGINES A Thesis by KENNETH HAROLD ROSEGAY Submitted to the Graduate College of Texas ASM University in partial fulfillment of the requirement for the degree... of MASTER OF SCIENCE December 1982 Major Subject: Mechanical Engineering A CYCLE SIMULATION OF COAL PARTICLE FUELED RECIPROCATING INTERNAL-COMBUSTION ENGINES A Thesis by KENNETH HAROLD ROSEGAY Approved as to style and content by; J. A. Caton...

Rosegay, Kenneth Harold

1982-01-01

256

Fuel properties of eleven vegetable oils  

SciTech Connect

Eleven vegetable oils that can be grown as domestic field crops were identified for inclusion in a comparative study of chemical and fuel properties. Sample lots of each oil were subjected to ASTM tests appropriate for diesel fuels. The tests identified some problem areas with vegetable oil fuels. The oil samples were also characterized chemically and certain fuel properties were correlated to chemical compositions.

Goering, C.E.; Daugherty, M.J.; Heakin, A.J.; Pryde, E.H.; Schwab, A.W.

1982-11-01

257

Advanced coal-fueled gas turbine systems: Subscale combustion testing. Topical report, Task 3.1  

SciTech Connect

This is the final report on the Subscale Combustor Testing performed at Textron Defense Systems` (TDS) Haverhill Combustion Laboratories for the Advanced Coal-Fueled Gas Turbine System Program of the Westinghouse Electric Corp. This program was initiated by the Department of Energy in 1986 as an R&D effort to establish the technology base for the commercial application of direct coal-fired gas turbines. The combustion system under consideration incorporates a modular staged, rich-lean-quench, Toroidal Vortex Slogging Combustor (TVC) concept. Fuel-rich conditions in the first stage inhibit NO{sub x} formation from fuel-bound nitrogen; molten coal ash and sulfated sorbent are removed, tapped and quenched from the combustion gases by inertial separation in the second stage. Final oxidation of the fuel-rich gases, and dilution to achieve the desired turbine inlet conditions are accomplished in the third stage, which is maintained sufficiently lean so that here, too, NO{sub x} formation is inhibited. The primary objective of this work was to verify the feasibility of a direct coal-fueled combustion system for combustion turbine applications. This has been accomplished by the design, fabrication, testing and operation of a subscale development-type coal-fired combustor. Because this was a complete departure from present-day turbine combustors and fuels, it was considered necessary to make a thorough evaluation of this design, and its operation in subscale, before applying it in commercial combustion turbine power systems.

Not Available

1993-05-01

258

Effects of fuel-injector design on ultra-lean combustion performance  

NASA Technical Reports Server (NTRS)

Emissions data were obtained for six fuel injector configurations tested with ultra lean combustion. Fuel injectors included three multiple source designs and three configurations using a single air assist injector. Only the multiple source fuel injectors provided acceptable emissions. Values of 16g CO/kg fuel, 1.9g HC/kg fuel, and 19.g NO2/kg fuel were obtained for the combustion temperature range of 1450 to 1700 K for both a high blockage 19 source injector and a low blockage 41 source injector. It was shown that high fuel injector pressure drop may not be required to achieve low emissions performance at high inlet air temperature when the fuel is well dispersed in the airstream.

Anderson, D. N.

1981-01-01

259

The properties of hydrogen as fuel tomorrow in sustainable energy system for a cleaner planet  

Microsoft Academic Search

The Global energy system transition from fossil fuel to hydrogen utilization is described. Environmental benefits of the combustion of hydrogen are reported. World carbon emissions from fossil fuel are schematized in connection with the opportunities of using hydrogen. The atomic hydrogen\\/carbon ratio and chemical properties of hydrogen are described. Pollutants of the energy system in our planet and hydrogen production

Magdalena Momirlan; T. N. Veziroglu

2005-01-01

260

Compression ignition engine having fuel system for non-sooting combustion and method  

SciTech Connect

A direct injection compression ignition internal combustion engine includes a fuel system having a nozzle extending into a cylinder of the engine and a plurality of spray orifices formed in the nozzle. Each of the spray orifices has an inner diameter dimension of about 0.09 mm or less, and define inter-orifice angles between adjacent spray orifice center axes of about 36.degree. or greater such that spray plumes of injected fuel from each of the spray orifices combust within the cylinder according to a non-sooting lifted flame and gas entrainment combustion pattern. Related methodology is also disclosed.

Bazyn, Timothy; Gehrke, Christopher

2014-10-28

261

Combustion Products of Petroleum Jet Fuel, a FischerľTropsch Synthetic Fuel, and a Biomass Fatty Acid Methyl Ester Fuel for a Gas Turbine Engine  

Microsoft Academic Search

We report combustion emissions data for several alternatives to petroleum based Jet A jet fuel, including a natural gasľderived FischerľTropsch (FT) synthetic fuel; a 50\\/50 blend of the FT synthetic fuel with Jet A-1; a 20\\/80 blend of a fatty acid methyl ester (FAME) with jet fuel; and a 40\\/60 blend of FAME with jet fuel. The chief distinguishing features

Michael T. Timko; Scott C. Herndon; Elena de la Rosa Blanco; Ezra C. Wood; Zhenhong Yu; Richard C. Miake-Lye; W. Berk Knighton; Linda Shafer; Matthew J. DeWitt; Edwin Corporan

2011-01-01

262

Synthetic fuel aromaticity and staged combustion. First quarterly technical progress report, September 23-December 31, 1980  

SciTech Connect

Synthetic liquid fuels, otherwise referred to as synfuels or coal-derived liquids, are probably best characterized from a combustion-environmental point of view as low in hydrogen, low in sulfur, high in nitrogen, and high in aromatics. As a consequence two of the more critical problems in synfuel combustion are NO/sub x/ formation and soot formation (and polycyclic organic matter). This program is directed to these two issues. At first hand the solutions to burning synfuels high in aromatics and fuel-bound nitrogen are diametrically opposed, i.e., high temperature and excess air keep soot levels down, low temperatures and vitiated air keep nitrogen oxide levels down. Staged combustion however offers a logical solution to the above. This program separates and analyzes the synfuel combustion problem via its component parts and then puts them together again phenomenologically via the stage combustion process.

Levy, Arthur; Longanbach, James R.; Chan, Lisa K.

1981-01-28

263

Implications of Low Particulate Matter Emissions on System Fuel Efficiency for High Efficiency Clean Combustion  

SciTech Connect

Advanced diesel combustion regimes such as High Efficiency Clean Combustion (HECC) offer the benefits of reduced engine out NOX and particulate matter (PM) emissions. Lower PM emissions during advanced combustion reduce the demand on diesel particulate filters (DPFs) and can, thereby, reduce the fuel penalty associated with DPF regeneration. In this study, a SiC DPF was loaded and regenerated on a 1.7-liter 4-cylinder diesel engine operated in conventional and advanced combustion modes at different speed and load conditions. A diesel oxidation catalyst (DOC) and a lean NOX trap (LNT) were also installed in the exhaust stream. Five steady-state speed and load conditions were weighted to estimate Federal Test Procedure (FTP) fuel efficiency. The DPF was loaded using lean-rich cycling with frequencies that resulted in similar levels of NOX emissions downstream of the LNT. The pressure drop across the DPF was measured at a standard point (1500 rpm, 5.0 bar) before and after loading, and a P rise rate was determined for comparison between conventional and advanced combustion modes. Higher PM emissions in conventional combustion resulted in a higher rate of backpressure rise across the DPF at all of the load points leading to more frequent DPF regenerations and higher fuel penalty. The fuel penalty during conventional combustion was 4.2% compared with 3.1% for a mixture of conventional and advanced modes.

Parks, II, James E [ORNL; Prikhodko, Vitaly Y [ORNL] [ORNL

2009-01-01

264

Retene emission from residential solid fuels in China and evaluation of retene as a unique marker for soft wood combustion.  

PubMed

Retene (1-methyl-7-isopropylphenanthrene) is often used as a marker for softwood combustion and for polycyclic aromatic hydrocarbon (PAH) source apportionment. The emission factors of retene (EF(RET)s) from 11 crop residues, 27 firewood fuels, and 5 coals were measured using traditional rural Chinese stoves. Retene was measured in combustion emissions from all of the residential fuels tested and EF(RET)s varied significantly among the fuels due to the differences in fuel properties and combustion conditions. EF(RET)s for pine (0.34 ▒ 0.08 mg/kg) and larch (0.29 ▒ 0.22 mg/kg) were significantly higher than those of other wood types, including fir and cypress (0.081 ▒ 0.058 mg/kg). However, EF(RET)s for crop residues varied from 0.048 ▒ 0.008 to 0.37 ▒ 0.14 mg/kg and were not significantly lower than those for softwood (0.074 ▒ 0.026 to 0.34 ▒ 0.08 mg/kg). The EF(RET)s for coal were very high and ranged from 2.2 ▒ 1.5 (anthracite briquette) to 187 ▒ 113 mg/kg (raw bituminous chunk). EF(RET) was positively correlated with EFs of coemitted particulate matter (EF(PM)) and phenanthrene (EF(PHE)) for crop residue and coal, but not for wood. In addition, the ratios of EF(PHE)/EF(RET) and EF(PM)/EF(RET) for coals were much lower than those for crop residues and wood. These data suggest that retene is not a unique PAH marker for softwood combustion and that coal combustion, in particular, should be taken into account when retene is used for PAH source apportionment. PMID:22452486

Shen, Guofeng; Tao, Shu; Wei, Siye; Zhang, Yanyan; Wang, Rong; Wang, Bin; Li, Wei; Shen, Huizhong; Huang, Ye; Yang, Yifeng; Wang, Wei; Wang, Xilong; Simonich, Staci L Massey

2012-04-17

265

Biomass Fuel Characterization : Testing and Evaluating the Combustion Characteristics of Selected Biomass Fuels : Final Report May 1, 1988-July, 1989.  

SciTech Connect

Results show that two very important measures of combustion efficiency (gas temperature and carbon dioxide based efficiency) varied by only 5.2 and 5.4 percent respectively. This indicates that all nine different wood fuel pellet types behave very similarly under the prescribed range of operating parameters. The overall mean efficiency for all tests was 82.1 percent and the overall mean temperature was 1420 1{degree}F. Particulate (fly ash) ad combustible (in fly ash) data should the greatest variability. There was evidence of a relationship between maximum values for both particulate and combustible and the percentages of ash and chlorine in the pellet fuel. The greater the percentage of ash and chlorine (salt), the greater was the fly ash problem, also, combustion efficiency was decreased by combustible losses (unburned hydrocarbons) in the fly ash. Carbon monoxide and Oxides of Nitrogen showed the next greatest variability, but neither had data values greater than 215.0 parts per million (215.0 ppm is a very small quantity, i.e. 1 ppm = .001 grams/liter = 6.2E-5 1bm/ft{sup 3}). Visual evidence indicates that pellets fuels produced from salt laden material are corrosive, produce the largest quantities of ash, and form the only slag or clinker formations of all nine fuels. The corrosion is directly attributable to salt content (or more specifically, chloride ions and compounds formed during combustion). 45 refs., 23 figs., 19 tabs.

Bushnell, Dwight J.; Haluzok, Charles; Dadkhah-Nikoo, Abbas

1990-04-01

266

40 CFR 1065.120 - Fuel properties and fuel temperature and pressure.  

Code of Federal Regulations, 2014 CFR

...Fuel properties and fuel temperature and pressure. 1065.120 Section 1065.120...Fuel properties and fuel temperature and pressure. (a) Use fuels as specified in...manufacturer specifies fuel temperature and pressure tolerances and the location where...

2014-07-01

267

Cyclic Combustion Variations in Dual Fuel Partially Premixed Pilot-Ignited Natural Gas Engines  

SciTech Connect

Dual fuel pilot ignited natural gas engines are identified as an efficient and viable alternative to conventional diesel engines. This paper examines cyclic combustion fluctuations in conventional dual fuel and in dual fuel partially premixed low temperature combustion (LTC). Conventional dual fueling with 95% (energy basis) natural gas (NG) substitution reduces NOx emissions by almost 90%t relative to straight diesel operation; however, this is accompanied by 98% increase in HC emissions, 10 percentage points reduction in fuel conversion efficiency (FCE) and 12 percentage points increase in COVimep. Dual fuel LTC is achieved by injection of a small amount of diesel fuel (2-3 percent on an energy basis) to ignite a premixed natural gas├?┬?├?┬?├?┬?├?┬ó├?┬?├?┬?├?┬?├?┬?├?┬?├?┬?├?┬?├?┬?air mixture to attain very low NOx emissions (less than 0.2 g/kWh). Cyclic variations in both combustion modes were analyzed by observing the cyclic fluctuations in start of combustion (SOC), peak cylinder pressures (Pmax), combustion phasing (Ca50), and the separation between the diesel injection event and Ca50 (termed ├?┬?├?┬?├?┬?├?┬ó├?┬?├?┬?├?┬?├?┬?├?┬?├?┬?├?┬?├?┬?relative combustion phasing├?┬?├?┬?├?┬?├?┬ó├?┬?├?┬?├?┬?├?┬?├?┬?├?┬?├?┬?├?┬Ł). For conventional dual fueling, as % NG increases, Pmax decreases, SOC and Ca50 are delayed, and cyclic variations increase. For dual fuel LTC, as diesel injection timing is advanced from 20├?┬?├?┬?├?┬?├?┬?├?┬?├?┬?├?┬?├?┬░ to 60├?┬?├?┬?├?┬?├?┬?├?┬?├?┬?├?┬?├?┬░BTDC, the relative combustion phasing is identified as an important combustion parameter along with SoC, Pmax, and CaPmax. For both combustion modes, cyclic variations were characterized by alternating slow and fast burn cycles, especially at high %NG and advanced injection timings. Finally, heat release return maps were analyzed to demonstrate thermal management strategies as an effective tool to mitigate cyclic combustion variations, especially in dual fuel LTC.

Srinivasan, K. K.; Krishnan, S. R.

2012-05-09

268

Characterizing droplet combustion of pure and multi-component liquid fuels in a microgravity environment  

NASA Technical Reports Server (NTRS)

The importance of understanding the effects of fuel composition, length scales, and other parameters on the combustion of liquid fuels has motivated the examination of simple flames which have easily characterized flow fields and hence, the potential of being modeled accurately. One such flame for liquid fuel combustion is the spherically symmetric droplet flame which can be achieved in an environment with sufficiently low gravity (i.e., low buoyancy). To examine fundamental characteristics of spherically symmetric droplet combustion, a drop tower facility has been employed to provide a microgravity environment to study droplet combustion. This paper gives a brief review of results obtained over the past three years under NASA sponsorship (grant NAG3-987).

Jackson, Gregory S.; Avedisian, C. Thomas

1993-01-01

269

Comparative study of combustion product emissions of Pakistani coal briquettes and traditional Pakistani domestic fuels  

SciTech Connect

A comparative emissions study was conducted on combustion products of various solid domestic cooking fuels; the objective was to compare relative levels of organic and inorganic toxic emissions from traditional Pakistani fuels (wood, wood charcoal, and dried animal dung) with manufactured low-rank coal briquettes (Lakhra and Sor- Range coals) under conditions simulating domestic cooking. A small combustion shed 12 m[sup 3] internal volume, air exchange rate 14 h[sup [minus]1] was used to simulate south Asian cooking rooms. 200-g charges of the various fuels were ignited in an Angethi stove located inside the shed, then combusted to completion; effluents from this combustion were monitored as a function of time. Measurements were made of respirable particulates, volatile and semi-volatile organics, CO, SO[sub 2], and NO[sub x]. Overall it appears that emissions from coal briquettes containing combustion amendments (slaked lime, clay, and potassium nitrate oxidizer) are no greater than emissions from traditional fuels, and in some cases are significantly lower; generally, emissions are highest for all fuels in the early stages of combustion.

Wachter, E.A.; Gammage, R.B.; Haas, J.W. III; Wilson, D.L. (Oak Ridge National Lab., TN (United States)); DePriest, J.C.; Wade, J. (Midwest Technical, Inc., Oak Ridge, TN (United States)); Ahmad, N.; Sibtain, F.; Zahid Raza, M. (Pakistan Council of Scientific and Industrial Research Labs., Karachi (Pakistan))

1992-10-01

270

Comparative study of combustion product emissions of Pakistani coal briquettes and traditional Pakistani domestic fuels  

SciTech Connect

A comparative emissions study was conducted on combustion products of various solid domestic cooking fuels; the objective was to compare relative levels of organic and inorganic toxic emissions from traditional Pakistani fuels (wood, wood charcoal, and dried animal dung) with manufactured low-rank coal briquettes (Lakhra and Sor- Range coals) under conditions simulating domestic cooking. A small combustion shed 12 m{sup 3} internal volume, air exchange rate 14 h{sup {minus}1} was used to simulate south Asian cooking rooms. 200-g charges of the various fuels were ignited in an Angethi stove located inside the shed, then combusted to completion; effluents from this combustion were monitored as a function of time. Measurements were made of respirable particulates, volatile and semi-volatile organics, CO, SO{sub 2}, and NO{sub x}. Overall it appears that emissions from coal briquettes containing combustion amendments (slaked lime, clay, and potassium nitrate oxidizer) are no greater than emissions from traditional fuels, and in some cases are significantly lower; generally, emissions are highest for all fuels in the early stages of combustion.

Wachter, E.A.; Gammage, R.B.; Haas, J.W. III; Wilson, D.L. [Oak Ridge National Lab., TN (United States); DePriest, J.C.; Wade, J. [Midwest Technical, Inc., Oak Ridge, TN (United States); Ahmad, N.; Sibtain, F.; Zahid Raza, M. [Pakistan Council of Scientific and Industrial Research Labs., Karachi (Pakistan)

1992-10-01

271

Study of PAH emission from the solid fuels combustion in residential furnaces.  

PubMed

The procedure for and results of a test study of polycyclic aromatic hydrocarbon (PAH) emission from a few types of solid fuels combustion in residential furnaces of various designs typical for Belarus are discussed. Greatest levels of PAH emission were detected from domestic wastes and wood waste combustion. Lowest levels of PAH emission are from peat briquette combustion. It was found that PAH concentration in off-gases from firewood combustion also varies significantly depending on the type of wood: the highest values of PAH are typical for waste gases from birch firewood combustion in comparison with pine firewood combustion. Draft PAH emission factors are proposed with intended application for emission inventory of such installations. PMID:15519469

Kakareka, Sergey V; Kukharchyk, Tamara I; Khomich, Valery S

2005-01-01

272

1 Characterization of carbonaceous aerosols outflow from India and 2 Arabia: Biomass/biofuel burning and fossil fuel combustion  

E-print Network

/biofuel burning and fossil fuel combustion 3 S. A. Guazzotti,1 D. T. Suess,1,2 K. R. Coffee,1,3 P. K. Quinn,4 T. S, or proximate sources. Aerosol and trace gas 21 measurements provide evidence that emissions from fossil fuel Peninsula, where dominance of fossil fuel combustion is suggested by 30 results from single

Dickerson, Russell R.

273

The origin of organic pollutants from the combustion of alternative fuels: Phase 5/6 report  

SciTech Connect

As part of the US Department of Energy National Renewable Energy Laboratory program on alternative automotive fuels, the subcontractor has been conducting studies on the origin and fate of organic pollutants from the combustion of alternative fuels. Laboratory experiments were conducted simulating cold start of four alterative fuels (compressed natural gas, liquefied petroleum gas, methanol-gasoline mix, and ethanol-gasoline mix) using a commercial three-way catalyst under fuel-lean conditions. This report summarizes the results of these experiments. It appears that temperature of the catalyst is a more important parameter for fuel conversion and pollutant formation than oxygen concentration or fuel composition.

Sidhu, S.; Graham, J.; Taylor, P.; Dellinger, B. [Univ. of Dayton, OH (United States). Research Inst.

1998-05-01

274

Performance Evaluation of a High Bandwidth Liquid Fuel Modulation Valve for Active Combustion Control  

NASA Technical Reports Server (NTRS)

At the NASA Glenn Research Center, a characterization rig was designed and constructed for the purpose of evaluating high bandwidth liquid fuel modulation devices to determine their suitability for active combustion control research. Incorporated into the rig s design are features that approximate conditions similar to those that would be encountered by a candidate device if it were installed on an actual combustion research rig. The characterized dynamic performance measures obtained through testing in the rig are planned to be accurate indicators of expected performance in an actual combustion testing environment. To evaluate how well the characterization rig predicts fuel modulator dynamic performance, characterization rig data was compared with performance data for a fuel modulator candidate when the candidate was in operation during combustion testing. Specifically, the nominal and off-nominal performance data for a magnetostrictive-actuated proportional fuel modulation valve is described. Valve performance data were collected with the characterization rig configured to emulate two different combustion rig fuel feed systems. Fuel mass flows and pressures, fuel feed line lengths, and fuel injector orifice size was approximated in the characterization rig. Valve performance data were also collected with the valve modulating the fuel into the two combustor rigs. Comparison of the predicted and actual valve performance data show that when the valve is operated near its design condition the characterization rig can appropriately predict the installed performance of the valve. Improvements to the characterization rig and accompanying modeling activities are underway to more accurately predict performance, especially for the devices under development to modulate fuel into the much smaller fuel injectors anticipated in future lean-burning low-emissions aircraft engine combustors.

Saus, Joseph R.; DeLaat, John C.; Chang, Clarence T.; Vrnak, Daniel R.

2012-01-01

275

Combustion characteristics of fuel droplets with addition of nano and micron-sized aluminum particles  

E-print Network

Combustion characteristics of fuel droplets with addition of nano and micron-sized aluminum Aluminum nanoparticles Microexplosion Particle aggregation a b s t r a c t The burning characteristics of fuel droplets containing nano and micron-sized aluminum particles were investigated. Particle size

Qiao, Li

276

EXPERIMENTAL STUDY ON HOMOGENEOUS CHARGE COMPRESSION IGNITION COMBUSTION WITH PRIMARY REFERENCE FUEL  

Microsoft Academic Search

By mixing iso-octane with octane number 100 and normal heptane with octane number 0, it was possible to obtain a primary reference fuel (PRF) with octane rating between 0 and 100. The influences of PRF fuel's octane number on the combustion characteristics, operation range, performance, and emissions characteristics of homogeneous charge compression ignition (HCCI) engine were investigated. The experiments were

MINGFA YAO; BO ZHANG; ZUNQING ZHENG; ZHENG CHEN

2007-01-01

277

Air or air and fuel mixture flow control in valve controlled internal combustion engines  

Microsoft Academic Search

In order to provide a controlled turbulence or angular momentum of air, air and fuel mixtures or similar fluids to be injected into the cylinder chamber of valve controlled internal combustion engines, control vanes are provided in close proximity to the valve retaining ring. The vanes deflect the flow of the air\\/fuel mixture without restricting the flow thus increasing the

1979-01-01

278

Air pollution from aircraft. [jet exhaust - aircraft fuels/combustion efficiency  

NASA Technical Reports Server (NTRS)

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.

Heywood, J. B.; Chigier, N. A.

1975-01-01

279

Advanced modeling of large-scale oxy-fuel combustion processes  

E-print Network

-fuel combustion (Yin, 2012). Reference [1] Yin, C.; Johansen, L.C.R.; Rosendahl, L.; K├Žr, S.K. "A new weighted sum and implementation". Energy & Fuels 2010; 24(12): 6275-82. [2] Yin, C.; Rosendahl, L.; K├Žr, S.K. "Chemistry

Yin, Chungen

280

ASSESSMENT OF ORGANIC CONTAMINANTS IN EMISSIONS FROM REFUSE-DERIVED FUEL COMBUSTION  

EPA Science Inventory

Organic contaminants in emissions from refuse-derived fuel combustion were investigated in a 20-inch-diameter atmospheric fluidized-bed combustor. Combinations of coal/EcoFuel/MSW/toluene were burned inthe combustor with temperatures ranging from 1250 to 1550 degrees F. A Source ...

281

Method of operating an internal combustion engine with solvent refined coal as a fuel  

Microsoft Academic Search

A method of using solvent refined coal as a fuel for an internal combustion engine is disclosed. The fuel is provided in finely divided form and is aspirated into the cylinder on a suction stroke and heated by compression to a point at which the finely divided solid material liquefies into a fine spray. The liquid spray is then ignited

1976-01-01

282

Fine and ultrafine particles generated during fluidized bed combustion of different solid fuels  

SciTech Connect

The paper reports an experimental study carried out with a 110-mm ID fluidized bed combustor focused on the characterization of particulates formation/emission during combustion of coal and non-fossil solid fuels. Fuels included: a bituminous coal, a commercial predried and granulated sludge (GS), a refuse-derived fuel (RDF), and a biomass waste (pine seed shells). Stationary combustion experiments were carried out analyzing the fate of fuel ashes. Fly ashes collected at the combustor exhaust were characterized both in terms of particle size distribution and chemical composition, with respect to both trace and major elements. Tapping-Mode Atomic Force Microscopy (TM-AFM) technique and high-efficiency cyclone-type collector devices were used to characterize the size and morphology of the nanometric-and micronic-size fractions of fly ash emitted at the exhaust respectively. Results showed that during the combustion process: I) the size of the nanometric fraction ranges between 2 and 65 nm; ii) depending on the fuel tested, combustion-assisted attrition or the production of the primary ash particles originally present in the fuel particles, are responsible of fine particle generation. The amount in the fly ash of inorganic compounds is larger for the waste-derived fuels, reflecting the large inherent content of these compounds in the parent fuels.

Urciuolo, M.; Barone, A.; D'Alessio, A.; Chirone, R. [CNR, Rome (Italy). Institute of Research for Combustion

2008-12-15

283

Combustion and emissions characteristics of a compression-ignition engine using dual ammonia-diesel fuel  

Microsoft Academic Search

This study investigated the performance of a compression-ignition engine using a dual-fuel approach with ammonia and diesel fuel. With the world's increasing need for alternative energy and clean emissions, ammonia stands out as a viable candidate since its combustion does not produce the known greenhouse gas, carbon dioxide. Ammonia is one of the world's most synthesized chemicals and its infrastructure

Aaron Reiter

2009-01-01

284

Synthetic and Jet Fuels Pyrolysis for Cooling and Combustion Applications.  

E-print Network

and P Gillard PRISME, IUT Bourges, 63, avenue de Lattre de Tassigny ┬ş 18000 Bourges, France Large heat.e. 5000 km.h-1) and to the combustion heat release. If passive and ablative protections are a way phenomenon (heat and mass transfers, pyrolysis, combustion) in a cooling channel surrounding a SCRamjet

Boyer, Edmond

285

Fuel reforming for scramjet thermal management and combustion optimization  

E-print Network

the cooling of the engine, since even composite materials can't withstand the large heat load found fast in order to avoid long combustion chamber caused by supersonic internal flow and short residence...) seems to be more promising from a combustion point of view. * Aerospace engineer, emeric

Paris-Sud XI, Universit├ę de

286

Increase in the rate of fuel combustion on addition of nanosized carbon particles  

NASA Astrophysics Data System (ADS)

Nanosized carbon fuel additives were formed by ultrasonic crushing of graphitized films or by subjecting ethanol to an electric discharge. The obtained specimens of fuel were tested on a setup for rapid adiabatic compression. Under conditions of ultrasonic dispersion, a wide spectrum of particle sizes was observed, and their influence on the characteristics of combustion turned out to be insignificant. When ethanol was treated by an electric discharge, spherical or plane carbon nanoclusters and various transient shapes, as well as liquid components, were synthesized. The resulting fuel displayed a substantial increase in the rate of combustion.

Shushkov, S. V.; Genarova, T. N.; Leshchevich, V. V.; Penyazkov, O. G.; Gusakova, S. V.; Egorov, A. S.; Govorov, M. I.; Prismotrov, Yu. A.

2012-07-01

287

Combustion-derived substances in deep basins of Puget Sound: historical inputs from fossil fuel and biomass combustion.  

PubMed

Reconstructions of 250 years historical inputs of two distinct types of black carbon (soot/graphitic black carbon (GBC) and char-BC) were conducted on sediment cores from two basins of the Puget Sound, WA. Signatures of polycyclic aromatic hydrocarbons (PAHs) were also used to support the historical reconstructions of BC to this system. Down-core maxima in GBC and combustion-derived PAHs occurred in the 1940s in the cores from the Puget Sound Main Basin, whereas in Hood Canal such peak was observed in the 1970s, showing basin-specific differences in inputs of combustion byproducts. This system showed relatively higher inputs from softwood combustion than the northeastern U.S. The historical variations in char-BC concentrations were consistent with shifts in climate indices, suggesting an influence of climate oscillations on wildfire events. Environmental loading of combustion byproducts thus appears as a complex function of urbanization, fuel usage, combustion technology, environmental policies, and climate conditions. PMID:21236534

Kuo, Li-Jung; Louchouarn, Patrick; Herbert, Bruce E; Brandenberger, Jill M; Wade, Terry L; Crecelius, Eric

2011-04-01

288

Progress on the investigation of coal-water slurry fuel combustion in a medium-speed diesel engine; Part 6: In-cylinder combustion photography studies  

SciTech Connect

In the GE 7FDL single cylinder research diesel engine, in-cylinder high-speed photographic studies were conducted on coal-water slurry (CWS) fuel combustion. Distinct flames of pilot and CWS combustion were noticed. It was proven that the coal fuel burns after piston impingement and secondary atomization. Agglomerated particles will develop when combustion conditions are not favorable. Cylinder pressure data were simultaneously recorded for each film frame. Heat release data can thus be produced for each photo study. Most of the findings of earlier combustion studies on engine performance were confirmed.

Hsu, B.D.; Branyon, D.P. (General Electric Co., Erie, PA (United States). Transportation Systems)

1993-10-01

289

Synthetic fuels handbook: properties, process and performance  

SciTech Connect

The handbook is a comprehensive guide to the benefits and trade-offs of numerous alternative fuels, presenting expert analyses of the different properties, processes, and performance characteristics of each fuel. It discusses the concept systems and technology involved in the production of fuels on both industrial and individual scales. Chapters 5 and 7 are of special interest to the coal industry. Contents: Chapter 1. Fuel Sources - Conventional and Non-conventional; Chapter 2. Natural Gas; Chapter 3. Fuels From Petroleum and Heavy Oil; Chapter 4. Fuels From Tar Sand Bitumen; Chapter 5. Fuels From Coal; Chapter 6. Fuels From Oil Shale; Chapter 7. Fuels From Synthesis Gas; Chapter 8. Fuels From Biomass; Chapter 9. Fuels From Crops; Chapter 10. Fuels From Wood; Chapter 11. Fuels From Domestic and Industrial Waste; Chapter 12. Landfill Gas. 3 apps.

Speight, J. [University of Utah, UT (United States)

2008-07-01

290

Combustion and deposition, erosion, and corrosion tests of coal turbine fuels  

SciTech Connect

This paper discusses the results obtained from the rich-quench-lean (RQL) combustion system running on distillate fuel and coal water slurry (CWS). Estimates of fuel bound nitrogen (FBN) yield indicate that rich lean combustion is successful in reducing the yield from coal water slurry fuel to between 8% and 12%. Some improvements in combustion efficiency are required when burning coal water slurry to reduce carbon monoxide and unburned hydrocarbons to acceptable levels. These improvements are achievable by increasing the lean zone residence time. Further testing is planned to investigate the effects of residence time in more detail. The planned deposition, erosion, and corrosion (DEC) testing will evaluate alternative approaches for protection from deposition, erosion, and corrosion of turbines operating with coal derived fuels.

Wilkes, C.; Wenglarz, R.; Clark, D.W.

1985-01-01

291

Combustion characteristics of GAP-coated boron particles and the fuel-rich solid propellant  

SciTech Connect

A process was employed that permits the coating of energetic glycidyl azide polymer (GAP) on the boron surface. Ignition and combustion behavior of single particle pure crystalline boron and GAP-coated boron at atmospheric pressure was studied experimentally by injecting the particles into the stream of hot gaseous environment of a flat-flame burner using premixed propane-oxygen-nitrogen gases. Chopped streak photographic observation was used to measure the ignition and combustion time. The flame temperature was fixed around 2,343 K, but under wider O{sub 2} level range than previous investigations. Measurement results show that GAP coating can shorten boron particle ignition delay time, however, the effect diminishes as the O{sub 2} level in combustion gas decreases. Possible mechanisms based on relevant reactions and heat effects were proposed. Combustion characteristics of fuel-rich solid propellants based on GAP-coated amorphous boron particles and uncoated ones were compared using different techniques such as combustion phenomena observations by a windowed strand burner, quenched propellant surface morphology analysis by scanning electron microscope, and combustion residues size analysis from the quenched particle collection bomb experiments. It was concluded that GAP-coated amorphous-boron-based fuel-rich propellants exhibit more vigorous combustion phenomena, higher burning rates, and a lesser extent of residue agglomeration than the uncoated baseline propellant. Moreover, reaction mechanisms were proposed to elucidate the combustion products obtained in this study.

Shyu, I.M. [Chung Cheng Inst. of Technology, Tashi (Taiwan, Province of China). Dept. of Applied Chemistry] [Chung Cheng Inst. of Technology, Tashi (Taiwan, Province of China). Dept. of Applied Chemistry; Liu, T.K. [Chung Shan Inst. of Science and Technology, Lungtan (Taiwan, Province of China). Chemical System Research Division] [Chung Shan Inst. of Science and Technology, Lungtan (Taiwan, Province of China). Chemical System Research Division

1995-03-01

292

Methodology development of a time-resolved in-cylinder fuel oxidation analysis: Homogeneous charge compression ignition combustion study application  

SciTech Connect

A technique was developed and applied to understand the mechanism of fuel oxidation in an internal combustion engine. This methodology determines the fuel and concentrations of various intermediates during the combustion cycle. A time-resolved measurement of a large number of species is the objective of this work and is achieved by the use of a sampling probe developed in-house. A system featuring an electromagnetically actuated sampling valve with internal N{sub 2} dilution was developed for sampling gases coming from the combustion chamber. Combustion species include O{sub 2}, CO{sub 2}, CO, NO{sub x}, fuel components, and hydrocarbons produced due to incomplete combustion of fuel. Combustion gases were collected and analyzed with the objectives of analysis by an automotive exhaust analyzer, separation by gas chromatography, and detection by flame ionization detection and mass spectrometry. The work presented was processed in a homogeneous charge compression ignition combustion mode context. (author)

Nowak, L.; Guibert, P.; Cavadias, S. [Universite de Pierre et Marie Curie, Institut Jean Le Rond D'Alembert CNRS UMR 7190, 2 place de la Gare de Ceinture, 78210 Saint Cyr l'Ecole (France); Dupre, S.; Momique, J.C. [PSA Peugeot Citroen, Centre Technique de Velizy, Route de Gizy, 78943 Velizy-Villacoublay (France)

2008-08-15

293

Controlling the composition, microstructure, electrical and magnetic properties of LiFe5O8 powders synthesized by sol gel auto-combustion method using urea as a fuel  

NASA Astrophysics Data System (ADS)

Nanocrystalline lithium ferrite LiFe5O8 powders were synthesized by the sol gel auto-combustion method from the corresponding metal nitrates using urea as a fuel. DTA results showed that the LiFe5O8 phase started to form at temperature around 385 ░C. X-ray diffraction analysis indicates that all compositions were formed in a single-phase cubic spinel structure at different annealing temperatures from 400 to 800 ░C for 2 h. The lattice parameter was found to decrease whereas the particle size was increased with annealing temperature. The frequency exponent "s" of lithium ferrite lies in the range 0.5?s?1, which confirmed the electron hopping between Fe2+ and Fe3+ ions. The electron mobility in LiFe5O8 samples ranged from 0.05 to 0.29 eV, which clearly indicated that the present lithium ferrites have semiconductor-like behavior. The saturation magnetization was increased on increasing the annealing temperature up to 800 ░C. High saturation magnetization (Ms=51.9 emu/g) was achieved for the ferrite powders produced at annealing temperature 800 ░C for 2 h.

Rashad, M. M.; El-Shaarawy, M. G.; Shash, N. M.; Maklad, M. H.; Afifi, F. A.

2015-01-01

294

Fuels-combustion research. Annual report, 10 October 1986-30 September 1987  

SciTech Connect

After studying soot formation in normal diffusion flames, near and slightly sooting inverse diffusion flames were investigated to determine the key intermediates to soot formation. The results indirectly confirm that the initial number density of soot particles that form scale with aromatic formation just prior to soot inception. Correlations exist between a fuel's sooting tendency as measured by the Princeton smoke-height experiment and the extent of aromatic formation measured in both inverse and normal diffusion flames. Work on the oxidation of the aromatics present in jet propulsion fuels continues with th major effort directed at the dialkylated benzenes. The major study concerned the oxidation of para-xylene. The results indicate oxidation of one side chain at a time before the benzene ring is attached. There is a linear decay of the fuel and the major species detected were toluene, benzene, p-tolualdehyde, p-ethyltoluene and carbon monoxide. Kinetics steps leading to these intermediates are given. Combustion-property observations of isolated boron-slurry droplets were extended to in-house boron/JP-10 slurries with and without surfactants. The experimental results revealed that stabilizing agents are responsible for the violent disruption of the primary slurry droplet and strongly support the previously proposed hypothesis of the formation of the impermeable shell and subsequent disruption phenomena.

Dryer, F.L.; Glassman, I.; Williams, F.A.

1987-10-31

295

Apparatus and method for operating internal combustion engines from variable mixtures of gaseous fuels  

DOEpatents

An apparatus and method for utilizing any arbitrary mixture ratio of multiple fuel gases having differing combustion characteristics, such as natural gas and hydrogen gas, within an internal combustion engine. The gaseous fuel composition ratio is first sensed, such as by thermal conductivity, infrared signature, sound propagation speed, or equivalent mixture differentiation mechanisms and combinations thereof which are utilized as input(s) to a "multiple map" engine control module which modulates selected operating parameters of the engine, such as fuel injection and ignition timing, in response to the proportions of fuel gases available so that the engine operates correctly and at high efficiency irrespective of the gas mixture ratio being utilized. As a result, an engine configured according to the teachings of the present invention may be fueled from at least two different fuel sources without admixing constraints.

Heffel, James W. (Lake Matthews, CA); Scott, Paul B. (Northridge, CA); Park, Chan Seung (Yorba Linda, CA)

2011-11-01

296

Study Into Combustion of Sewage Sludge as Energetic Fuel / Badania Spalania OSADËW ?CIEKOWYCH Jako Paliwa Energetycznego  

NASA Astrophysics Data System (ADS)

Along with the development of civilisation, it can be observed that the amount of waste of different type is growing and the preparation process for further usage of the waste or the utilization process differs. What is to be focused on is municipal sewage sludge which, due to its energetic properties, constitutes a valuable fuel. The problem of usage of municipal sewage sludge remains still unsolved, which stems both from the increasing amount of such waste, and from the lack of properly adjusted systems for thermal processing thereof. What is of an additional obstacle are the increasingly stricter legal regulations regarding disposal of sewage sludge after the year 2013; hence, it is necessary to consider various benefits resulting from thermal processing of such waste. This work presents an overview of methods of disposal of sewage sludge, taking into consideration, in particular, thermal methods including the process of combustion and co-combustion as a means of successful utilization. The research section of the work presents the results of study into the mechanism and kinetics of combustion of sewage sludge in various conditions of the process carried out in air flow. Combustion of sewage sludge has been compared against combustion of coal and biomass. Wraz z rozwojem cywilizacji zaobserwowa? mo?na post?puj?ce powstawanie rˇ?nego rodzaju odpadˇw rˇ?ni?cych si?, m.in. sposobem przygotowania do dalszego wykorzystania, czy procesem utylizacji. Na szczegˇln? uwag? zas?uguj? komunalne osady ?ciekowe, ktˇre z uwagi na w?a?ciwo?ci energetyczne stanowi? cenne paliwo. Problem wykorzystania komunalnych osadˇw ?ciekowych jest nadal otwarty, a wynika to zarˇwno z rosn?cej produkcji tych odpadˇw, jak i braku odpowiednio przystosowanych instalacji do termicznego ich przekszta?cania. Dodatkowym utrudnieniem s? zaostrzaj?ce si? przepisy prawne dotycz?ce sk?adowania osadˇw ?ciekowych po 2013 r. sk?aniaj?ce tym samym do rozwa?a? nad korzy?ciami p?yn?cymi z termicznej obrˇbki tych odpadˇw. W pracy przedstawiono przegl?d sposobˇw unieszkodliwiania osadˇw ?ciekowych ze szczegˇlnym uwzgl?dnieniem metod termicznych, g?ˇwnie spalania i wspˇ?spalania jako drogi do ich sukcesywnej utylizacji. W cz??ci badawczej pracy zaprezentowano wyniki bada? mechanizmu i kinetyki spalania osadˇw ?ciekowych w rˇ?nych warunkach procesu prowadzonego w strumieniu powietrza. Spalanie osadˇw ?ciekowych porˇwnano ze spalaniem w?gla oraz biomasy.

Kijo-Kleczkowska, Agnieszka; ?roda, Katarzyna; Otwinowski, Henryk

2013-12-01

297

Effects of Catalysts on Emissions of Pollutants from Combustion Processes of Liquid Fuels  

NASA Astrophysics Data System (ADS)

The dynamic growth of the use of non-renewable fuels for energy purposes results in demand for catalysts to improve their combustion process. The paper describes catalysts used mainly in the processes of combustion of motor fuels and fuel oils. These catalysts make it possible to raise the efficiency of oxidation processes simultanously reducing the emission of pollutants. The key to success is the selection of catalyst compounds that will reduce harmful emissions of combustion products into the atmosphere. Catalysts are introduced into the combustion zone in form of solutions miscible with fuel or with air supplied to the combustion process. The following compounds soluble in fuel are inclused in the composition of the described catalysts: organometallic complexes, manganese compounds, salts originated from organic acids, ferrocen and its derivatives and sodium chloride and magnesium chloride responsible for burning the soot (chlorides). The priority is to minimize emissions of volatile organic compounds, nitrogen oxides, sulphur oxides, and carbon monoxide, as well as particulate matter.

Bok, Agnieszka; Guzia?owska-Tic, Joanna; Tic, Wilhelm Jan

2014-12-01

298

Combustion characteristics of dry coal-powder-fueled adiabatic diesel engine: Final report  

SciTech Connect

This report describes the progress and findings of a research program aimed at investigating the combustion characteristics of dry coal powder fueled diesel engine. During this program, significant achievements were made in overcoming many problems facing the coal-powder-fueled engine. The Thermal Ignition Combustion System (TICS) concept was used to enhance the combustion of coal powder fuel. The major coal-fueled engine test results and accomplishments are as follows: design, fabrication and engine testing of improved coal feed system for fumigation of coal powder to the intake air; design, fabrication and engine testing of the TICS chamber made from a superalloy material (Hastelloy X); design, fabrication and engine testing of wear resistant chrome oxide ceramic coated piston rings and cylinder liner; lubrication system was improved to separate coal particles from the contaminated lubricating oil; control of the ignition timing of fumigated coal powder by utilizing exhaust gas recirculation (EGR) and variable TICS chamber temperature; coal-fueled engine testing was conducted in two configurations: dual fuel (with diesel pilot) and 100% coal-fueled engine without diesel pilot or heated intake air; cold starting of the 100% coal-powder-fueled engine with a glow plug; and coal-fueled-engine was operated from 800 to 1800 rpm speed and idle to full load engine conditions.

Kakwani, R.M.; Kamo, R.

1989-01-01

299

Non-equilibrium plasma assisted combustion of low heating value fuels  

NASA Astrophysics Data System (ADS)

This paper describes the effects of non-equilibrium air plasma generated by a dielectric barrier discharge (DBD) on the combustion of low heating value fuels. The experimental results indicate that addition of a very small amount of energy to the air flow in the form of DBD significantly improves the flame stability. Moreover, main combustion characteristics such as flame propagation speed, combustion intensity and lean blow-off limits are also enhanced by the effect of plasma. Some active radicals such as excited O atom and excited N2 molecule are observed by spectrograph in the discharge area. Based on the results of numerical investigation we can conclude that these active radicals generated in discharge area can accelerate the production rate of active OH radical which plays a key role in the oxidation process of low heating value fuel, and thus the whole combustion process is accelerated.

Hu, Hongbin; Song, Quanbin; Xu, Yanji; Li, Gang; Nie, Chaoqun

2013-06-01

300

Multiphase CFD-based models for chemical looping combustion process: Fuel reactor modeling  

SciTech Connect

Chemical looping combustion (CLC) is a flameless two-step fuel combustion that produces a pure CO2 stream, ready for compression and sequestration. The process is composed of two interconnected fluidized bed reactors. The air reactor which is a conventional circulating fluidized bed and the fuel reactor which is a bubbling fluidized bed. The basic principle is to avoid the direct contact of air and fuel during the combustion by introducing a highly-reactive metal particle, referred to as oxygen carrier, to transport oxygen from the air to the fuel. In the process, the products from combustion are kept separated from the rest of the flue gases namely nitrogen and excess oxygen. This process eliminates the energy intensive step to separate the CO2 from nitrogen-rich flue gas that reduce the thermal efficiency. Fundamental knowledge of multiphase reactive fluid dynamic behavior of the gasľsolid flow is essential for the optimization and operation of a chemical looping combustor. Our recent thorough literature review shows that multiphase CFD-based models have not been adapted to chemical looping combustion processes in the open literature. In this study, we have developed the reaction kinetics model of the fuel reactor and implemented the kinetic model into a multiphase hydrodynamic model, MFIX, developed earlier at the National Energy Technology Laboratory. Simulated fuel reactor flows revealed high weight fraction of unburned methane fuel in the flue gas along with CO2 and H2O. This behavior implies high fuel loss at the exit of the reactor and indicates the necessity to increase the residence time, say by decreasing the fuel flow rate, or to recirculate the unburned methane after condensing and removing CO2.

Jung, Jonghwun (ANL); Gamwo, I.K.

2008-04-21

301

Combustion studies of coal-derived solid fuels. Part IV. Correlation of ignition temperatures from thermogravimetry and free-floating experiments  

USGS Publications Warehouse

The usefulness of TG as an efficient and practical method to characterize the combustion properties of fuels used in large-scale combustors is of considerable interest. Relative ignition temperatures of a lignite, an anthracite, a bituminous coal and three chars derived from this coal were measured by a free-floating technique. These temperatures were correlated with those estimated from TG burning profiles of the fuels. ?? 1992.

Rostam-Abadi, M.; DeBarr, J.A.; Chen, W.T.

1992-01-01

302

GRH 12-01 Fireside Corrosion in Oxy-fuel Combustion Poster 0108  

SciTech Connect

The goals are to: (1) Achieve 90% CO{sub 2} capture at no more than a 35% increase in levelized cost of electricity of post-combustion capture for new and existing conventional coal-fired power plants; (2) Provide high-temperature corrosion information to aid in materials development and selection for oxy-fuel combustion; and (3) Identify corrosion mechanism and behavior differences between air- and oxy-firing.

G. R. Holcomb; J. Tylczak; G. H. Meier; B. Lutz; K. Jung; N. Mu; N. M. Yanar; F. S. Pettit; J. Zhu; A. Wise; D. Laughlin; S. Sridhar

2012-05-20

303

Effect of broad properties fuel on injector performance in a reverse flow combustor  

NASA Technical Reports Server (NTRS)

The effect of fuel type on the performance of various fuel injectors was investigated in a reverse flow combustor. Combustor performance and emissions are documented for simplex pressure atomizing, spill flow, and airblast fuel injectors using a broad properties fuel and compared with performance using Jet A fuel. Test conditions simulated a range of flight conditions including sea level take off, low and high altitude cruise, as well as a parametric evaluation of the effect of increased combustor loading. The baseline simplex injector produced higher emission levels with corresponding lower combustion efficiency with the broad properties fuel. There was little or not loss in performance by the two advanced concept injectors with the broad properties fuel. The airblast injector proved to be especially insensitive to fuel type.

Raddlebaugh, S. M.; Norgren, C. T.

1983-01-01

304

Performance\\/combustion characteristics of six Canadian alternative fuels tested in a bombardier medium speed diesel  

Microsoft Academic Search

Six experimental fuels representative of Canadian future fuel options were tested against a reference fuel in a bombardier 12 cylinder, 4 stroke, 3000 hp, medium speed diesel. The reference fuel was a straight run ASTM number2-d. Each fuel was analyzed for physical and chemical properties. The engine was tested under a marine application propeller law load curve at 8 different

R. G. Grimsey; R. T. Stoneman; G. D. Webster; D. Y. Chan

1985-01-01

305

Analysis of the relation between thermal decomposition and PM reduction of bio-diesel mixed fuels in diesel combustion atmosphere  

Microsoft Academic Search

To investigate particulate matter (PM) reduction mechanism by blending bio-diesel fuel (BDF) with diesel fuel, thermal decomposition during diesel combustion was analyzed using a plug flow reactor and a co-flow diffusion burner. \\

H. Noge; Y. Kidoguchi

306

Stability analysis of a liquid fuel annular combustion chamber. M.S. Thesis  

NASA Technical Reports Server (NTRS)

High frequency combustion instability problems in a liquid fuel annular combustion chamber are examined. A modified Galerkin method was used to produce a set of modal amplitude equations from the general nonlinear partial differential acoustic wave equation in order to analyze the problem of instability. From these modal amplitude equations, the two variable perturbation method was used to develop a set of approximate equations of a given order of magnitude. These equations were modeled to show the effects of velocity sensitive combustion instabilities by evaluating the effects of certain parameters in the given set of equations.

Mcdonald, G. H.

1978-01-01

307

Sulfur emission from Victorian brown coal under pyrolysis, oxy-fuel combustion and gasification conditions.  

PubMed

Sulfur emission from a Victorian brown coal was quantitatively determined through controlled experiments in a continuously fed drop-tube furnace under three different atmospheres: pyrolysis, oxy-fuel combustion, and carbon dioxide gasification conditions. The species measured were H(2)S, SO(2), COS, CS(2), and more importantly SO(3). The temperature (873-1273 K) and gas environment effects on the sulfur species emission were investigated. The effect of residence time on the emission of those species was also assessed under oxy-fuel condition. The emission of the sulfur species depended on the reaction environment. H(2)S, SO(2), and CS(2) are the major species during pyrolysis, oxy-fuel, and gasification. Up to 10% of coal sulfur was found to be converted to SO(3) under oxy-fuel combustion, whereas SO(3) was undetectable during pyrolysis and gasification. The trend of the experimental results was qualitatively matched by thermodynamic predictions. The residence time had little effect on the release of those species. The release of sulfur oxides, in particular both SO(2) and SO(3), is considerably high during oxy-fuel combustion even though the sulfur content in Morwell coal is only 0.80%. Therefore, for Morwell coal utilization during oxy-fuel combustion, additional sulfur removal, or polishing systems will be required in order to avoid corrosion in the boiler and in the CO(2) separation units of the CO(2) capture systems. PMID:23301852

Chen, Luguang; Bhattacharya, Sankar

2013-02-01

308

Fuels combustion research. Final technical report, 1 October 1985-30 September 1988  

SciTech Connect

Studies of near and slightly sooting inverse and normal co-flow diffusion flames determined aromatics as the key intermediates to soot formation. The extent of aromatic formation correlated with the earlier Princeton smoke-height test results. The effect of oxygen addition to tightly bound fuels (ethene, ethyne and benzene) in diffusion flames was found to accelerate the pyrolysis and thus the soothing tendency, but not to affect other fuels in the temperature range of soot formation. Flow-reactor experiments determined oxidation kinetic results for the mono- and dialkylated aromatic components of jet fuels. Succinctly, it was found that the alkyl chains are attached initially and in the case of dialkylated compounds not simultaneously. Mechanisms have been presented. Results on boron-slurry droplet combustion were obtained and provided a basis for calculating when droplet disruption would occur. Questions with respect to boron-cloud combustion addressed mechanisms of ignition and combustion in the regime of chemical kinetic control.

Glassman, I.; Dryer, F.L.; Williams, F.A.

1988-11-30

309

A study on combustion behavior of a diesel fuel spray impinging on a wall  

SciTech Connect

Combustion characteristics of a diesel fuel spray impinging on a wall were studied, using a constant volume combustion vessel. Pressure and temperature inside the vessel, and fuel injection specification were set at the typical values of small DI diesel engines of 90--100 mm cylinder bore size. The indicated pressure analysis and combustion observation indicate that present analysis enables the evaluation of the mixture formation affected by impingement wall, corresponding to a small actual DI diesel engine. By lowering impingement wall temperature from 840 K to 620 K, ignition point shifts upstream along the spray from a portion near the wall, and ignition delay is shortened. Although ignition occurs earlier at shorter impingement length, its ignition time difference become less at shorter ignition delay condition, where, however, the heat release rate changes greatly and it gives a maximum at a certain impingement length. This value almost corresponds to the break up length of fuel spray.

Tomonaga, Takashi; Murai, Kazuyuki; Takano, Takayoshi; Sami, Hiroshi

1996-09-01

310

Ideal Temperature Rise Due to Constant-pressure Combustion of a JP-4 Fuel  

NASA Technical Reports Server (NTRS)

The ideal temperature rise due to the constant-pressure combustion of a methylene (CH sub 2) fuel was calculated. CH sub 2 fuel closely approximates MIL-F-5624 grade JP-4 fuel presently used in most turbojet and ram-jet engines. Charts are presented from which the ideal temperature rise or the ideal quantity of fuel required to obtain a specified combustion temperature may be obtained for any flight condition likely to be encountered with turbojet or ram-jet engines using this fuel. The charts are applicable only to a fuel having a hydrogen-carbon mass ratio of 0.168. They include a range of fuel-air ratios from 0 to 1.2 fraction of stoichiometric fuel-air ratio with dissociation taken into account, inlet-air temperatures from 400 degrees to 1600 degrees R, and combustion pressures from 1/16 to 64 atmospheres. The use of the charts is illustrated by several examples.

Huntley, S C

1955-01-01

311

Further investigation of the impact of the co-combustion of tire-derived fuel and petroleum coke on the petrology and chemistry of coal combustion products  

SciTech Connect

A Kentucky cyclone-fired unit burns coal and tire-derived fuel, sometimes in combination with petroleum coke. A parallel pulverized combustion (pc) unit at the same plant burns the same coal, without the added fuels. The petrology, chemistry, and sulfur isotope distribution in the fuel and resulting combustion products was investigated for several configurations of the fuel blend. Zinc and Cd in the combustion products are primarily contributed from the tire-derived fuel, the V and Ni are primarily from the petroleum coke, and the As and Hg are probably largely from the coal. The sulfur isotope distribution in the cyclone unit is complicated due to the varying fuel sources. The electrostatic precipitator (ESP) array in the pc unit shows a subtle trend towards heavier S isotopic ratios in the cooler end of the ESP.

Hower, J.C.; Robertson, J.D.; Elswick, E.R.; Roberts, J.M.; Brandsteder, K.; Trimble, A.S.; Mardon, S.M. [University of Kentucky, Lexington, KY (United States). Center for Applied Energy Research

2007-07-01

312

MUNICIPAL WASTE COMBUSTION ASSESSMENT: FOSSIL FUEL CO-FIRING  

EPA Science Inventory

The report identifies refuse derived fuel (RDF) processing operations and various RDF types; describes such fossil fuel co-firing techniques as coal fired spreader stokers, pulverized coal wall fired boilers, pulverized coal tangentially fired boilers, and cyclone fired boilers; ...

313

Combustion characteristics of an agricultural diesel engine using biodiesel fuel  

Microsoft Academic Search

Biodiesel has great potential as an alternative fuel for diesel engines that would reduce air pollution. It is a domestically\\u000a produced, renewable fuel that can be manufactured from fresh or used vegetable oils, or from animal fats. In this study, a\\u000a biodiesel fuel derived from rice bran oil was tested as an alternative fuel for agricultural diesel engines. The emissions

Kyunghyun Ryu; Youngtaig Oh

2004-01-01

314

Laboratory test methods for combustion stability properties of solid propellants  

NASA Technical Reports Server (NTRS)

An overview is presented of experimental methods for determining the combustion-stability properties of solid propellants. The methods are generally based on either the temporal response to an initial disturbance or on external methods for generating the required oscillations. The size distribution of condensed-phase combustion products are characterized by means of the experimental approaches. The 'T-burner' approach is shown to assist in the derivation of pressure-coupled driving contributions and particle damping in solid-propellant rocket motors. Other techniques examined include the rotating-valve apparatus, the impedance tube, the modulated throat-acoustic damping burner, and the magnetic flowmeter. The paper shows that experimental methods do not exist for measuring the interactions between acoustic velocity oscillations and burning propellant.

Strand, L. D.; Brown, R. S.

1992-01-01

315

ORGANIC COMBUSTION FINGERPRINTS OF THREE COMMON HOME HEATING FUELS  

EPA Science Inventory

The paper discusses the chemical structures of three common home eating fuels: wood, coal, and No. 2 fuel oil. GC and GC/MS data are then presented which demonstrate how the thermal destruction of each fuel results in the production of a characteristic group of organic "fingerpri...

316

Development of high temperature air combustion technology in pulverized fossil fuel fired boilers  

SciTech Connect

High temperature air combustion (HTAC) is a promising technology for energy saving, flame stability enhancement and NOx emission reduction. In a conventional HTAC system, the combustion air is highly preheated by using the recuperative or regenerative heat exchangers. However, such a preheating process is difficult to implement for pulverized fossil fuel fired boilers. In this paper, an alternative approach is proposed. In the proposed HTAC system, a special burner, named PRP burner is introduced to fulfill the preheating process. The PRP burner has a preheating chamber with one end connected with the primary air and the other end opened to the furnace. Inside the chamber, gas recirculation is effectively established such that hot flue gases in the furnace can be introduced. Combustible mixture instead of combustion air is highly preheated by the PRP burner. A series of experiments have been conducted in an industrial scale test facility, burning low volatile petroleum coke and an anthracite coal. Stable combustion was established for burning pure petroleum coke and anthracite coal, respectively. Inside the preheating chamber, the combustible mixture was rapidly heated up to a high temperature level close to that of the hot secondary air used in the conventional HTAC system. The rapid heating of the combustible mixture in the chamber facilitates pyrolysis, volatile matter release processes for the fuel particles, suppressing ignition delay and enhancing combustion stability. Moreover, compared with the results measured in the same facility but with a conventional low NOx burner, NOx concentration at the furnace exit was at the same level when petroleum coke was burnt and 50% less when anthracite was burnt. Practicability of the HTAC technology using the proposed approach was confirmed for efficiently and cleanly burning fossil fuels. 16 refs., 10 figs., 1 tab.

Hai Zhang; Guangxi Yue; Junfu Lu; Zhen Jia; Jiangxiong Mao; Toshiro Fujimori; Toshiyuki Suko; Takashi Kiga [Tsinghua University, Beijing (China). Department of Thermal Engineering

2007-07-01

317

Performance, Efficiency, and Emissions Characterization of Reciprocating Internal Combustion Engines Fueled with Hydrogen\\/Natural Gas Blends  

Microsoft Academic Search

Hydrogen is an attractive fuel source not only because it is abundant and renewable but also because it produces almost zero regulated emissions. Internal combustion engines fueled by compressed natural gas (CNG) are operated throughout a variety of industries in a number of mobile and stationary applications. While CNG engines offer many advantages over conventional gasoline and diesel combustion engines,

Kirby S. Chapman; Amar Patil

2007-01-01

318

Modeling the Feasibility of Using Fuel Cells and Hydrogen Internal Combustion Engines in Remote Renewable Energy Systems: Preprint  

Microsoft Academic Search

Recent advances in hydrogen fuel cell and internal combustion engine technologies have enabled new energy options for supplying electrical power in remote, off-grid areas. The objective of this investigation is to determine under which conditions wind turbines and PV systems can feasibly power electrolyzers to generate and store hydrogen for remote power generation using fuel cells and internal combustion engines.

J. Cotrell; W. Pratt

2003-01-01

319

Experimental investigation on combustion and heat transfer characteristics in a furnace fueled with unconventional biomass fuels (date stones and palm stalks)  

Microsoft Academic Search

The combustion of date stones and palm stalks in a small scale furnace with a conical solid fuel bed is investigated experimentally. This investigation (to the best of the knowledge of the author) is the first addressing date stones as a new renewable energy source. Different experimental conditions are investigated where different fuel feed conditions and different combustion air flow

S.-A. B. Al-Omari

2006-01-01

320

Evaluating the manufacturability and combustion behaviors of sludge-derived fuel briquettes.  

PubMed

Based on the physical and chemical properties as well as calorific values of pulp sludge and textile sludge, this study investigates the differences between manufacturability, relationship between extrusion pressure and formability, as well as stability and combustion behaviors of extruded sludge-derived fuel briquettes (ESBB) and cemented sludge-derived fuel blocks (CSBB). The optimum proportion and relevant usage ESBB policies are proposed as well. Experimental results indicate that a large amount of water can be saved during the ESBB manufacturing process. Additionally, energy consumption decreases during the drying process. ESBB also has a more compact structure than that of CSBB, and its mean penetration loading is approximately 18.7 times higher as well. Moreover, the flame temperature of ESBB (624-968░C) is significantly higher than that of CSBB (393-517░C). Also, the dry bulk density and moisture regain of ESBB is significantly related to the penetration loading. Furthermore, the optimum mix proportion of ESBB is co-determined by the formability of pulp sludge and the calorific values of textile sludge. While considering the specific conditions (including formability, stability and calorific values), the recommended mix proportion for ESBB is PS50TS50. PMID:24913348

Chiou, Ing-Jia; Wu, I-Tsung

2014-10-01

321

3D computation of hydrogen-fueled combustion around turbine blade-effect of arrangement of injector holes-  

NASA Astrophysics Data System (ADS)

Recently, a number of environmental problems caused from fossil fuel combustion have been focused on. In addition, with the eventual depletion of fossil energy resources, hydrogen gas is expected to be an alternative energy resource in the near future. It is characterized by high energy per unit weight, high reaction rate, wide range of flammability and the low emission property. On the other hand, many researches have been underway in several countries to improve a propulsion system for an advanced aircraft. The system is required to have higher power, lighter weight and lower emissions than existing ones. In such a future propulsion system, hydrogen gas would be one of the promising fuels for realizing the requirements. Considering these backgrounds, our group has proposed a new cycle concept for hydrogen-fueled aircraft propulsion system. In the present study, we perform 3 dimensional computations of turbulent flow fields with hydrogen-fueled combustion around a turbine blade. The main objective is to clarify the influence of arrangement of hydrogen injector holes. Changing the chordwise and spanwise spacings of the holes, the 3 dimensional nature of the flow and thermal fields is numerically studied.

Yamamoto, Makoto; Ikeda, Junichi; Inaba, Kazuaki

2006-09-01

322

Fuel properties of eleven vegetable oils  

SciTech Connect

Eleven vegetable oils that can be grown as domestic field crops were identified for inclusion in a comparative study. Sample lots of each oil were subjected to ASTM tests appropriate for diesel fuels. The tests identified some problem areas with vegetable oil fuels. The oil samples were also characterized chemically and certain fuel properties were correlated to chemical composition. 10 refs.

Goering, C.E.; Schwab, A.W.; Daugherty, M.J.; Pryde, E.H.; Keakin, A.J.

1981-01-01

323

Internal combustion engines fueled by natural gasŚhydrogen mixtures  

Microsoft Academic Search

In this study, a survey of research papers on utilization of natural gasľhydrogen mixtures in internal combustion engines is carried out. In general, HC, CO2, and CO emissions decrease with increasing H2, but NOx emissions generally increase. If a catalytic converter is used, NOx emission values can be decreased to extremely low levels. Consequently, equivalence zero emission vehicles (EZEV) standards

S. Orhan Akansu; Zafer Dulger; Nafiz Kahraman; T. Nejat Veziro?lu

2004-01-01

324

Fuel-air mixing and combustion in a two-dimensional Wankel engine  

NASA Technical Reports Server (NTRS)

A two-equation turbulence model, an algebraic grid generalization method, and an approximate factorization time-linearized numerical technique are used to study the effects of mixture stratification at the intake port and gaseous fuel injection on the flow field and fuel-air mixing in a two-dimensional rotary engine model. The fuel distribution in the combustion chamber is found to be a function of the air-fuel mixture fluctuations at the intake port. It is shown that the fuel is advected by the flow field induced by the rotor and is concentrated near the leading apex during the intake stroke, while during compression, the fuel concentration is highest near the trailing apex and is lowest near the rotor. It is also found that the fuel concentration near the trailing apex and rotor is small except at high injection velocities.

Shih, T. I.-P.; Schock, H. J.; Ramos, J. I.

1987-01-01

325

Aviation fuel property effects on altitude relight  

NASA Technical Reports Server (NTRS)

The major objective of this experimental program was to investigate the effects of fuel property variation on altitude relight characteristics. Four fuels with widely varying volatility properties (JP-4, Jet A, a blend of Jet A and 2040 Solvent, and Diesel 2) were tested in a five-swirl-cup-sector combustor at inlet temperatures and flows representative of windmilling conditions of turbofan engines. The effects of fuel physical properties on atomization were eliminated by using four sets of pressure-atomizing nozzles designed to give the same spray Sauter mean diameter (50 + or - 10 micron) for each fuel at the same design fuel flow. A second series of tests was run with a set of air-blast nozzles. With comparable atomization levels, fuel volatility assumes only a secondary role for first-swirl-cup lightoff and complete blowout. Full propagation first-cup blowout were independent of fuel volatility and depended only on the combustor operating conditions.

Venkataramani, K.

1987-01-01

326

Combustion tests of a turbine simulator burning low Btu fuel from a fixed bed gasifier  

SciTech Connect

One of the most efficient and environmentally compatible coal fueled power generation technologies is the integrated gasification combined cycle (IGCC) concept. Commercialization of the IGCC/HGCU concept requires successful development of combustion systems for high temperature low Btu fuel in gas turbines. Toward this goal, a turbine combustion system simulator has been designed, constructed, and fired with high temperature low Btu fuel. Fuel is supplied by a pilot scale fixed bed gasifier and hot gas desulfurization system. The primary objectives of this project are: (1) demonstration of long term operability of the turbine simulator with high temperature low Btu fuel; (2) measurement of NO{sub x}, CO, and particulate emissions; and (3) characterization of particulates in the fuel as well as deposits in the fuel nozzle, combustor, and first stage nozzle. In a related project, a reduced scale rich-quench-lean (RQL) gas turbine combustor has been designed, constructed, and fired with simulated low Btu fuel. The overall objective of this project is to develop an RQL combustor with lower conversion of fuel bound nitrogen (FBN) to NO{sub x} than a conventional combustor.

Cook, C.S.; Abuaf, N.; Feitelberg, A.S.; Hung, S.L.; Najewicz, D.J.; Samuels, M.S.

1993-11-01

327

Developments in integrated pollutant removal for low-emission oxy-fuel combustion  

SciTech Connect

A complete coal combustion and flue gas treatment scheme was designed, constructed, and operated at bench scale as a product of cooperative research between US DOEĺs Albany Research Center (ARC) and Jupiter Oxygen Corporation. The combustion gas generated using this oxy-fuel coal combustion process was effectively captured using an integrated pollutant removal (IPR) process. Supporting laboratory-scale research focuses on elements of IPR such as extraction of particulates, SO2, and mercury, and on the character of the liquid and vapor phase compositions for the CO2 - N2 - O2 mixture at the temperature and pressure conditions found at the end of the process. Future pilot-scale work will be necessary to generate economic and engineering data that will apply to full-scale oxy-fuel/IPR systems.

Gerdemann, Stephen J.; Summers, Cathy A.; Oryshchyn, Danylo B.; Patrick, Brian (Jupiter Oxygen Corp.); Ochs, Thomas L.

2005-09-01

328

Combustible coal\\/water mixture for fuels and method of preparing same  

Microsoft Academic Search

Combustible fuel slurry compositions and methods for producing such compositions. The compositions comprise mixtures of particulate coal, water, wetting\\/dispersing agents for the coal and suspending agents for stabilizing the slurries. The suspending agents include clays such as attapulgite, sepiolite, bentonite and montmorillonite. The wetting\\/dispersing agents include anionic and non-ionic surface active agents.

E. W. Jr

1985-01-01

329

Knock prediction for dual fuel engines by using a simplified combustion model.  

PubMed

The present work used a methane-air mixture chemical kinetics scheme consisting of 119 elementary reaction steps and 41 chemical species to develop a simplified combustion model for prediction of the knock in dual fuel engines. Calculated values by the model for natural gas operation showed good agreement with corresponding experimental values over a broad range of operating conditions. PMID:12958720

Fei, Shao-mei; Liu, Zhen-tao; Yan, Zhao-da

2003-01-01

330

Domestic biomass fuel combustion and chronic bronchitis in two rural Bolivian villages  

Microsoft Academic Search

BACKGROUNDChronic bronchitis is an important public health problem worldwide. A study was undertaken to examine the association between exposure to air pollution from domestic biomass fuel combustion and chronic bronchitis in two rural Bolivian highland villages: a village in which cooking is done exclusively indoors and a village in which cooking is done primarily outdoors. Apart from this difference, the

R Albalak; A R Frisancho; G J Keeler

1999-01-01

331

Modeling of combustion instabilities and their active control in a gas fueled combustor  

Microsoft Academic Search

This study deals with the development of simplified models for simulation of combustion instabilities and their active control. Modulation of a part of the fuel supply is used to damp instabilities by generating heat release oscillations that are out of phase with the existing pressure oscillations. A model that accounts for mixing using a heuristic source term has been developed,

Rajendran Mohanraj

1998-01-01

332

RECENT DEVELOPMENTS OF EMISSION CONTROL TECHNOLOGY IN THE UNITED STATES FOR FOSSIL FUEL COMBUSTION SOURCES  

EPA Science Inventory

The paper discusses control of air pollution from fossil fuel combustion. ntil recently, this meant abatement of smoke (particulate), sulfur dioxide, and oxides of nitrogen. With growing concern about global climate change, carbon dioxide has been added to the list. The paper inc...

333

Separation of particulate from flue gas of fossil fuel combustion and gasification  

Microsoft Academic Search

The gas from combustion or gasification of fossil fuel contains fly ash and other particulates. The fly ash is separated from the gas in a plurality of standleg moving granular-bed filter modules. Each module includes a dipleg through which the bed media flows into the standleg. The bed media forms a first filter bed having an upper mass having a

W. C. Yang; R. A. Newby; T. E. Lippert

1997-01-01

334

Separation of particulate from flue gas of fossil fuel combustion and gasification  

Microsoft Academic Search

The gas from combustion or gasification of fossil fuel contains flyash and other particulate. The flyash is separated from the gas in a plurality of standleg moving granular-bed filter modules. Each module includes a dipleg through which the bed media flows into the standleg. The bed media forms a first filter bed having an upper mass having a first frusto-conical

Wen-Ching Yang; Richard A. Newby; Thomas E. Lippert

1997-01-01

335

QUANTIFYING HAZARDOUS SPECIES IN PARTICULATE MATTER DERIVED FROM FOSSIL-FUEL COMBUSTION  

EPA Science Inventory

An analysis protocol that combines X-ray absorption near-edge structure spectroscopy with selective leaching has been developed to examine hazardous species in size- segregated particulate matter (PM) samples derived from the combustion of fossil fuels. The protocol has been used...

336

EPA/IFP EUROPEAN WORKSHOP ON THE EMISSION ON NITROUS OXIDE FROM FOSSIL FUEL COMBUSTION  

EPA Science Inventory

The report summarizes the proceedings of an EPA/Institut Francais du Petrole (IFP) cosponsored workshop addressing direct nitrous oxide (N2O) emission from fossil fuel combustion. The third in a series, it was held at the IFP in Rueil-Malmaison, France, on June 1-2, 1988. Increas...

337

HAZARDOUS AIR POLLUTANTS FROM THE COMBUSTION OF AN EMULSIFIED HEAVY FUEL OIL IN A FIRETUBE BOILER  

EPA Science Inventory

The report gives results of measuring emissions of hazardous air pollutants (HAPs) from the combustion flue gases of a No. 6 fuel oil, both with and without an emulsifying agent, in a 2.5 million Btu/hr (732 kW) firetube boiler with the purpose of determining the impacts of the e...

338

CARCINOGENICITY OF HOUSEHOLD SOLID FUEL COMBUSTION AND OF HIGH-TEMPERATURE FRYING  

EPA Science Inventory

In October, 2006, 19 scientists from eight countries met at the International Agency for Research on Cancer (IARC) in Lyon, France, to assess the carcinogenicity of household solid fuel combustion (coal and biomass) and of high-temperature frying. These assessments will be publi...

339

CHARACTERIZATION OF FINE PARTICULATE MATTER PRODUCED BY COMBUSTION OF RESIDUAL FUEL OIL  

EPA Science Inventory

Combustion experiments were carried out on four different residual fuel oils in a 732-kW boiler. PM emission samples were separated aerodynamically by a cyclone into fractions that were nominally less than (PM2.5) and greater (PM2.5+) that 2.5 micrometers in diameter. However, ex...

340

Method and apparatus for oxidizing a fuel in an internal combustion engine  

Microsoft Academic Search

A mixture of air, oxygen and engine exhaust gases is added to a fuel and fed to an internal combustion engine in controlled amounts to reduce the amount of toxic material formed. The oxygen is supplied by a plurality of oxygen converters arranged in parallel so that one or more of the converters are charging while one or more of

Vierling

1977-01-01

341

Flame blowout and pollutant emissions in vitiated combustion of conventional and bio-derived fuels  

Microsoft Academic Search

The widening gap between the demand and supply of fossil fuels has catalyzed the exploration of alternative sources of energy. Interest in the power, water extraction and refrigeration (PoWER) cycle, proposed by the University of Florida, as well as the desirability of using biofuels in distributed generation systems, has motivated the exploration of biofuel vitiated combustion. The PoWER cycle is

Bhupinder Singh

2009-01-01

342

Theoretical Combustion Performance of Several High-Energy Fuels for Ramjet Engines  

NASA Technical Reports Server (NTRS)

An analytical evaluation of the air and fuel specific-impulse characteristics of magnesium, magnesium octene-1 slurries, aluminum, aluminum octene-1 slurries, boron, boron octene-1 slurries, carbon, hydrogen, alpha-methylnaphthalene, diborane, pentaborane, and octene-1 is presented. While chemical equilibrium was assumed in the combustion process, the expansion was assumed to occur at fixed composition.

Tower, Leonard K; Breitwieser, Roland; Gammon, Benson E

1958-01-01

343

Initial Observations on the Free Droplet Combustion Characteristics of Water-In-Fuel Emulsionsć  

Microsoft Academic Search

A new mechanical technique for the production of well characterized small diameter isolated free droplets of multi-component and emulsified liquids is described. The technique is employed in development of an experimental facility to generate, inject, and combust free droplets of liquid fuels in a well defined, hot convective atmosphere. Initial observations of the burning characteristics of isolated free droplets of

J. C. LASHERAS; A. C. FERNANDEZ-PELLO; F. L. DRYER

1979-01-01

344

Health effects of fossil fuel combustion products: report of a workshop.  

PubMed Central

Judgemental positions are presented on research priorities in regard to the health effects from stationary sources of fossil fuel combustion products. Hopefully, they can provide guidance for efforts to ensure that national energy needs are met with minimum environmental and economic burdens on the public. The major areas include epidemiological studies, controlled biological studies, mutagenesis and carcinogenesis, trace elements, monitoring and analysis. PMID:1227856

Comar, C L; Nelson, N

1975-01-01

345

Oxy-fuel Combustion and Integrated Pollutant Removal as Retrofit Technologies for Removing CO2 from Coal Fired Power Plants  

SciTech Connect

One third of the US installed capacity is coal-fired, producing 49.7% of net electric generation in 20051. Any approach to curbing CO2 production must consider the installed capacity and provide a mechanism for preserving this resource while meeting CO2 reduction goals. One promising approach to both new generation and retrofit is oxy-fuel combustion. Using oxygen instead of air as the oxidizer in a boiler provides a concentrated CO2 combustion product for processing into a sequestration-ready fluid.... Post-combustion carbon capture and oxy-fuel combustion paired with a compression capture technology such as IPR are both candidates for retrofitting pc combustion plants to meet carbon emission limits. This paper will focus on oxy-fuel combustion as applied to existing coal power plants.

Ochs, T.L.; Oryshchyn, D.B.; Summers, C.A.; Gerdemann, S.J.

2001-01-01

346

Finial Scientific/Technical Report: Application of a Circulating Fluidized Bed Process for the Chemical Looping Combustion of Solid Fuel  

SciTech Connect

Chemical Looping Combustion is a novel combustion technology for the inherent separation of the greenhouse gas, CO{sub 2}. In 1983, Richter and Knoche proposed reversible combustion, which utilized both the oxidation and reduction of metal. Metal associated with its oxidized form as an oxygen carrier was circulated between two reactors--oxidizer and reducer. In the reducer, the solid oxygen carrier reacts with the fuel to produce CO{sub 2}, H{sub 2}O and elemental metal only. Pure CO{sub 2} will be obtained in the exit gas stream from the reducer after H{sub 2}O is condensed. The pure CO{sub 2} is ready for subsequent sequestration. In the oxidizer, the elemental metal reacts with air to form metal oxide and separate oxygen from nitrogen. Only nitrogen and some unused oxygen are emitted from the oxidizer. The advantage of CLC compared to normal combustion is that CO{sub 2} is not diluted with nitrogen but obtained in a relatively pure form without any energy needed for separation. In addition to the energy-free purification of CO{sub 2}, the CLC process also provides two other benefits. First, NO{sub x} formation can be largely eliminated. Secondly, the thermal efficiency of a CLC system is very high. Presently, the CLC process has only been used with natural gas. An oxygen carrier based on an energy balance analysis and thermodynamics analysis was selected. Copper (Cu) seems to be the best choice for the CLC system for solid fuels. From this project, the mechanisms of CuO reduction by solid fuels may be as follows: (1) If pyrolysis products of solid fuels are available, reduction of CuO could start at about 400 C or less. (2) If pyrolysis products of solid fuels are unavailable and the reduction temperature is lower, reduction of CuO could occur at an onset temperature of about 500 C, char gasification reactivity in CO{sub 2} was lower at lower temperatures. (3) If pyrolysis products of solid fuels are unavailable and the reduction temperature is higher than 750 C, all reaction reactivities were improved, especially the CO{sub 2} gasification reactivity of char. Thus, the reduction of CuO by the gasification product CO could proceed quickly. Based on the results obtained, the following coal characteristics would be desirable for the Chemical Looping Combustion process: high volatile matter with a high reactivity of the char produced. PRB coal meets these criteria while being comparatively less expensive and also very abundant. The high moisture content present in PRB coal might also increase the reactivity for char gasification through the development of pore structure and specific surface area in the char during pyrolysis. Biomass materials are also suitable, considering the reaction mechanism of CLC system of solid fuels. The feasibility of the chemical looping combustion process of solid fuels was verified by focusing on PRB coal and biomass. Based on PRB coal as the preferred solid fuel in the development of the CLC system, the mass, energy and system in a dual reactor recirculation system has been determined. In the Cu oxidation tests, it was confirmed that the heating rate is the most important effect on the Cu oxidation process. Lower heating rates and lower operational temperatures would result in incomplete conversion of Cu to CuO. Cu{sub 2}O may be the intermediate product. The operating temperature did not affect the reaction rate of the oxidation process. Under any operating conditions, the exothermic properties are clearly shown.

Dr. Wei-Ping Pan; Dr. John T. Riley

2005-10-10

347

Fuel Effects on Combustion and Emissions of a Direct-Inection Diesel Engine Operating at Moderate to High Engine Speed and Load  

SciTech Connect

It is advantageous to increase the specific power output of diesel engines and to operate them at higher load for a greater portion of a driving cycle to achieve better thermal efficiency and thus reduce vehicle fuel consumption. Such operation is limited by excessive smoke formation at retarded injection timing and high rates of cylinder pressure rise at more advanced timing. Given this window of operation, it is desired to understand the influence of fuel properties such that optimum combustion performance and emissions can be retained over the range of fuels commonly available in the marketplace. It has been shown in previous studies that varying cetane number (CN) of diesel fuel has little effect on ignition delay at high engine load due to the domination of high cylinder temperature on ignition kinetics. The work here experimentally confirms that finding but also shows that emissions and combustion performance vary according to fuel reactivity. Data are examined from a direct-injection single cylinder research engine for eight common diesel fuels including soy-based biodiesel blends at two high load operating points with no exhaust gas recirculation (EGR) and at a moderate load with four levels of EGR. It is shown in the work that at high engine load where combustion is controlled by mixing processes, CN and other fuel properties have little effect on engine performance, although lower CN fuels produce a small increase in noise, smoke and CO emissions. Biodiesel blends increase NOX emissions and decreases CO and smoke emissions at high load, but otherwise have little effect on performance. At moderate load, higher CN fuels are more tolerant to EGR due to their better chemical reactivity at retarded injection timing, but all fuels produce comparable thermal efficiency at advanced combustion phasing regardless of EGR. In contrast to the high load conditions, there was no increase in NOX emissions for biodiesel at the moderate load condition. It is concluded that although higher CN does not significantly alter ignition delay at moderate to high loads it has a dominant influence on the acceptable injection timing range. Apart from CN effects, fuel oxygen content plays an independent role in reducing some emissions. It is therefore recommended that compensation for fuel ignitability and oxygen content be included in combustion control strategies to optimize emissions and performance of future diesel engines.

Szybist, James P [ORNL; Szymkowicz, Patrick G. [General Motors Corporation; Northrop, William F [General Motors Corporation

2012-01-01

348

Flame blowout and pollutant emissions in vitiated combustion of conventional and bio-derived fuels  

NASA Astrophysics Data System (ADS)

The widening gap between the demand and supply of fossil fuels has catalyzed the exploration of alternative sources of energy. Interest in the power, water extraction and refrigeration (PoWER) cycle, proposed by the University of Florida, as well as the desirability of using biofuels in distributed generation systems, has motivated the exploration of biofuel vitiated combustion. The PoWER cycle is a novel engine cycle concept that utilizes vitiation of the air stream with externally-cooled recirculated exhaust gases at an intermediate pressure in a semi-closed cycle (SCC) loop, lowering the overall temperature of combustion. It has several advantages including fuel flexibility, reduced air flow, lower flame temperature, compactness, high efficiency at full and part load, and low emissions. Since the core engine air stream is vitiated with the externally cooled exhaust gas recirculation (EGR) stream, there is an inherent reduction in the combustion stability for a PoWER engine. The effect of EGR flow and temperature on combustion blowout stability and emissions during vitiated biofuel combustion has been characterized. The vitiated combustion performance of biofuels methyl butanoate, dimethyl ether, and ethanol have been compared with n-heptane, and varying compositions of syngas with methane fuel. In addition, at high levels of EGR a sharp reduction in the flame luminosity has been observed in our experimental tests, indicating the onset of flameless combustion. This drop in luminosity may be a result of inhibition of processes leading to the formation of radiative soot particles. One of the objectives of this study is finding the effect of EGR on soot formation, with the ultimate objective of being able to predict the boundaries of flameless combustion. Detailed chemical kinetic simulations were performed using a constant-pressure continuously stirred tank reactor (CSTR) network model developed using the Cantera combustion code, implemented in C++. Results have been presented showing comparative trends in pollutant emissions generation, flame blowout stability, and combustion efficiency. (Full text of this dissertation may be available via the University of Florida Libraries web site. Please check http://www.uflib.ufl.edu/etd.html)

Singh, Bhupinder

349

Combustion characteristics of hydrogen. Carbon monoxide based gaseous fuels  

NASA Technical Reports Server (NTRS)

An experimental rig program was conducted with the objective of evaluating the combuston performance of a family of fuel gases based on a mixture of hydrogen and carbon monoxide. These gases, in addition to being members of a family, were also representative of those secondary fuels that could be produced from coal by various gasification schemes. In particular, simulated Winkler, Lurgi, and Blue-water low and medium energy content gases were used as fuels in the experimental combustor rig. The combustor used was originally designed as a low NOx rich-lean system for burning liquid fuels with high bound nitrogen levels. When used with the above gaseous fuels this combustor was operated in a lean-lean mode with ultra long residence times. The Blue-water gas was also operated in a rich-lean mode. The results of these tests indicate the possibility of the existence of an 'optimum' gas turbine hydrogen - carbon monoxide based secondary fuel. Such a fuel would exhibit NOx and high efficiency over the entire engine operating range. It would also have sufficient stability range to allow normal light-off and engine acceleration. Solar Turbines Incorporated would like to emphasize that the results presented here have been obtained with experimental rig combustors. The technologies generated could, however, be utilized in future commercial gas turbines.

Notardonato, J. J.; White, D. J.; Kubasco, A. J.; Lecren, R. T.

1981-01-01

350

Determination of alternative fuels combustion products: Phase 3 report  

SciTech Connect

This report describes the laboratory efforts to characterize particulate and gaseous exhaust emissions from a passenger vehicle operating on alternative fuels. Tests were conducted at room temperature (nominally 72 F) and 20 F utilizing the chassis dynamometer portion of the FTP for light-duty vehicles. Fuels evaluated include Federal RFG, LPG meeting HD-5 specifications, a national average blend of CNG, E85, and M85. Exhaust particulate generated at room temperature was further characterized to determine polynuclear aromatic content, trace element content, and trace organic constituents. For all fuels except M85, the room temperature particulate emission rate from this vehicle was about 2 to 3 mg/mile. On M85, the particulate emission rate was more than 6 mg/mile. In addition, elemental analysis of particulate revealed an order of magnitude more sulfur and calcium from M85 than any other fuel. The sulfur and calcium indicate that these higher emissions might be due to engine lubricating oil in the exhaust. For RFG, particulate emissions at 20 F were more than six times higher than at room temperature. For alcohol fuels, particulate emissions at 20 F were two to three times higher than at room temperature. For CNG and LPG, particulate emissions were virtually the same at 72 F and 20 F. However, PAH emissions from CNG and LPG were higher than expected. Both gaseous fuels had larger amounts of pyrene, 1-nitropyrene, and benzo(g,h,i)perylene in their emissions than the other fuels.

Whitney, K.A. [Southwest Research Inst., San Antonio, TX (United States)

1997-12-01

351

Testing and modeling liquefying fuel combustion in hybrid propulsion  

NASA Astrophysics Data System (ADS)

Hybrid motors are considered an alternative for space launchers due to their safety and high energetic performance. Nevertheless, classical hybrid combustors employing polymeric fuels are characterized by a low fuel regression rate resulting in low thrust levels that may not be adequate. This research presents experimental investigation and theoretical model of liquefying (paraffin-based) fuels, featuring high regression rates. The model developed includes an additional feature and mass loss mechanism, i. e., the liquid melt flowing along the grain. The test results exhibit a good correlation with the model predictions.

Weinstein, A.; Gany, A.

2013-03-01

352

Effect of co-firing on the properties of submicron aerosols from biomass combustion  

Microsoft Academic Search

As part of a more general study on particle formation process (and, specifically, the submicron fraction of the particle size distribution) in biomass combustion, the effect of combining biomass with other sulfur-enriched fuels (such as coal and coke) on particulate emissions has been investigated. Pulverized orujillo (an olive oil production process residue) combustion, alone, resulted in an important submicron particle

Santiago JimÚnez; Javier Ballester

2005-01-01

353

Aircraft Research and Technology for Future Fuels  

NASA Technical Reports Server (NTRS)

The potential characteristics of future aviation turbine fuels and the property effects of these fuels on propulsion system components are examined. The topics that are discussed include jet fuel supply and demand trends, the effects of refining variables on fuel properties, shekle oil processing, the characteristics of broadened property fuels, the effects of fuel property variations on combustor and fuel system performance, and combuster and fuel system technology for broadened property fuels.

1980-01-01

354

Chemical Kinetic Simulation of the Combustion of Bio-based Fuels  

SciTech Connect

Due to environmental and economic issues, there has been an increased interest in the use of alternative fuels. However, before widespread use of biofuels is feasible, the compatibility of these fuels with specific engines needs to be examined. More accurate models of the chemical combustion of alternative fuels in Homogeneous Charge Compression Ignition (HCCI) engines are necessary, and this project evaluates the performance of emissions models and uses the information gathered to study the chemical kinetics involved. The computer simulations for each alternative fuel were executed using the Chemkin chemical kinetics program, and results from the runs were compared with data gathered from an actual engine that was run under similar conditions. A new heat transfer mechanism was added to the existing model's subroutine, and simulations were then conducted using the heat transfer mechanism. Results from the simulation proved to be accurate when compared with the data taken from the actual engine. The addition of heat transfer produced more realistic temperature and pressure data for biodiesel when biodiesel's combustion was simulated in an HCCI engine. The addition of the heat transfer mechanism essentially lowered the peak pressures and peak temperatures during combustion of all fuels simulated in this project.

Ashen, Ms. Refuyat [Oak Ridge High School; Cushman, Ms. Katherine C. [Oak Ridge High School

2007-10-01

355

Shock-Dispersed-Fuel Charges: Combustion in Chambers and Tunnels  

Microsoft Academic Search

In previous studies we have investigated after-burning effects of a fuel-rich explosive (TNT). In that case the detonation only releases about 30% of the available energy, but generates a hot cloud of fuel that can burn in the ambient air, thus evoking an additional energy release that is distributed in space and time. The current series of small-scale experiments can

P Neuwald; H Reichenbach; A L Kuhl

2003-01-01

356

Study of effects of injector geometry on fuel-air mixing and combustion  

NASA Technical Reports Server (NTRS)

An implicit finite-difference method has been developed for computing the flow in the near field of a fuel injector as part of a broader study of the effects of fuel injector geometry on fuel-air mixing and combustion. Detailed numerical results have been obtained for cases of laminar and turbulent flow without base injection, corresponding to the supersonic base flow problem. These numerical results indicated that the method is stable and convergent, and that significant savings in computer time can be achieved, compared with explicit methods.

Bangert, L. H.; Roach, R. L.

1977-01-01

357

Large Eddy Simulation of the Fuel Injection in Scramjet Combustion Chambers  

NASA Astrophysics Data System (ADS)

Fuel injection in a typical scramjet combustion chamber is a very challenging flow to characterise either in ex- perimental or computational studies. It involves multi- species compressible turbulent features with complex coherent flow structures arising as a result of sonic fuel injection transverse or inclined to the free-stream supersonic flow. In this paper the fuel injection in the HyShot- II combustion chamber is studied using an Implicit LES method employing a modified very high order accurate numerical method. To gain accurate mean inflow boundary conditions, a thermally perfect gas formulation has been employed in preliminary simulations of the inlet ramp and cowl configuration. The results of these simulations are presented and validated against wind tunnel data.

Rana, Z. A.; Thornber, B. J. R.; Drikakis, D.

2011-08-01

358

Auto-Ignition and Combustion of Diesel Fuel in a Constant-Volume Bomb  

NASA Technical Reports Server (NTRS)

Report presents the results of a study of variations in ignition lag and combustion associated with changes in air temperature and density for a diesel fuel in a constant-volume bomb. The test results have been discussed in terms of engine performance wherever comparisons could be drawn. The most important conclusions drawn from this investigation are: the ignition lag was essentially independent of the injected fuel quantity. Extrapolation of the curves for the fuel used shows that the lag could not be greatly decreased by exceeding the compression-ignition engines. In order to obtain the best combustion and thermal efficiency, it was desirable to use the longest ignition lag consistent with a permissible rate of pressure rise.

Selden, Robert F

1938-01-01

359

Waste plastics as supplemental fuel in the blast furnace process: improving combustion efficiencies.  

PubMed

The possibility of using waste plastics as a source of secondary fuel in a blast furnace has been of recent interest. The success of this process, however, will be critically dependent upon the optimization of operating systems. For instance, the supply of waste plastics must be reliable as well as economically attractive compared with conventional secondary fuels such as heavy oil, natural gas and pulverized coal. In this work, we put special importance on the improvement of the combustibility of waste plastics as a way to enhance energy efficiency in a blast furnace. As experimental variables to approach this target, the effects of plastic particle size, blast temperature, and the level of oxygen enrichment were investigated using a custom-made blast model designed to simulate a real furnace. Lastly, the combustion efficiency of the mixture of waste plastics and pulverized coal was tested. The observations made from these experiments led us to the conclusion that with the increase of both blast temperature and the level of oxygen enrichment, and with a decrease in particle size, the combustibility of waste polyethylene could be improved at a given distance from the tuyere. Also it was found that the efficiency of coal combustion decreased with the addition of plastics; however, the combustion efficiency of mixture could be comparable at a longer distance from the tuyere. PMID:12220825

Kim, Dongsu; Shin, Sunghye; Sohn, Seungman; Choi, Jinshik; Ban, Bongchan

2002-10-14

360

High-density fuel combustion and cooling investigation. [kengine design  

NASA Technical Reports Server (NTRS)

The analysis, design, fabrication and testing of several engine configurations are discussed with respect to the combustion and heat transfer characteristics of LOX/RP-1 at chamber pressures between 6895 and 13790 kPa (1000 and 2000 psia). The different engine configurations discussed include: 8274 kPa and 13790 kPa (1200 psia and 2000 psia) chamber pressure injectors with like doublet and preatomized triplet elements; cooled and uncooled acoustic resonators; and graphite, regeneratively cooled and calorimetric chambers ranging in length from 27.9 to 37.5 cm (11 to 15 in.). A high pressure LOX/RP-1 spark igniter is also evaluated.

Labotz, R. J.; Rousar, D. C.; Valler, H. W.

1980-01-01

361

Mixing fuel particles for space combustion research using acoustics  

NASA Technical Reports Server (NTRS)

Part of the microgravity science to be conducted aboard the Shuttle (STS) involves combustion using solids, particles, and liquid droplets. The central experimental facts needed for characterization of premixed quiescent particle cloud flames cannot be adequately established by normal gravity studies alone. The experimental results to date of acoustically mixing a prototypical particulate, lycopodium, in a 5 cm diameter by 75 cm long flame tube aboard a Learjet aircraft flying a 20-sec low-gravity trajectory are described. Photographic and light detector instrumentation combine to measure and characterize particle cloud uniformity.

Burns, Robert J.; Johnson, Jerome A.; Klimek, Robert B.

1988-01-01

362

Mixing fuel particles for space combustion research using acoustics  

NASA Technical Reports Server (NTRS)

Part of the microgravity science to be conducted aboard the Shuttle (STS) involves combustion using solids, particles, and liquid droplets. The central experimental facts needed for characterization of premixed quiescent particle cloud flames cannot be adequately established by normal gravity studies alone. The experimental results to date of acoustically mixing a prototypical particulate, lycopodium, in a 5 cm diameter by 75 cm long flame tube aboard a Learjet aircraft flying a 20 sec low gravity trajectory are described. Photographic and light detector instrumentation combine to measure and characterize particle cloud uniformity.

Burns, Robert J.; Johnson, Jerome A.; Klimek, Robert B.

1988-01-01

363

Mixing fuel particles for space combustion research using acoustics  

NASA Astrophysics Data System (ADS)

Part of the microgravity science to be conducted aboard the Shuttle (STS) involves combustion using solids, particles, and liquid droplets. The central experimental facts needed for characterization of premixed quiescent particle cloud flames cannot be adequately established by normal gravity studies alone. This paper describes the experimental results to date of acoustically mixing a prototypical particulate, lycopodium, in a 5 cm diameter by 75 cm long flame tube aboard a Learjet aircraft flying a 20-sec low-gravity trajectory. Photographic and light detector instrumentation combine to measure and characterize particle cloud uniformity.

Burns, Robert J.; Johnson, Jerome A.; Klimek, Robert B.

1988-08-01

364

Impact of aviation non-CO? combustion effects on the environmental feasibility of alternative jet fuels.  

PubMed

Alternative fuels represent a potential option for reducing the climate impacts of the aviation sector. The climate impacts of alternatives fuel are traditionally considered as a ratio of life cycle greenhouse gas (GHG) emissions to those of the displaced petroleum product; however, this ignores the climate impacts of the non-CO(2) combustion effects from aircraft in the upper atmosphere. The results of this study show that including non-CO(2) combustion emissions and effects in the life cycle of a Synthetic Paraffinic Kerosene (SPK) fuel can lead to a decrease in the relative merit of the SPK fuel relative to conventional jet fuel. For example, an SPK fuel option with zero life cycle GHG emissions would offer a 100% reduction in GHG emissions but only a 48% reduction in actual climate impact using a 100-year time window and the nominal climate modeling assumption set outlined herein. Therefore, climate change mitigation policies for aviation that rely exclusively on relative well-to-wake life cycle GHG emissions as a proxy for aviation climate impact may overestimate the benefit of alternative fuel use on the global climate system. PMID:22106939

Stratton, Russell W; Wolfe, Philip J; Hileman, James I

2011-12-15

365

Polycyclic aromatic hydrocarbon emissions from the combustion of alternative fuels in a gas turbine engine.  

PubMed

We report on the particulate-bound polycyclic aromatic hydrocarbons (PAH) in the exhaust of a test-bed gas turbine engine when powered by Jet A-1 aviation fuel and a number of alternative fuels: Sasol fully synthetic jet fuel (FSJF), Shell gas-to-liquid (GTL) kerosene, and Jet A-1/GTL 50:50 blended kerosene. The concentration of PAH compounds in the exhaust emissions vary greatly between fuels. Combustion of FSJF produces the greatest total concentration of PAH compounds while combustion of GTL produces the least. However, when PAHs in the exhaust sample are measured in terms of the regulatory marker compound benzo[a]pyrene, then all of the alternative fuels emit a lower concentration of PAH in comparison to Jet A-1. Emissions from the combustion of Jet A-1/GTL blended kerosene were found to have a disproportionately low concentration of PAHs and appear to inherit a greater proportion of the GTL emission characteristics than would be expected from volume fraction alone. The data imply the presence of a nonlinear relation between fuel blend composition and the emission of PAH compounds. For each of the fuels, the speciation of PAH compounds present in the exhaust emissions were found to be remarkably similar (R(2) = 0.94-0.62), and the results do provide evidence to support the premise that PAH speciation is to some extent indicative of the emission source. In contrast, no correlation was found between the PAH species present in the fuel with those subsequently emitted in the exhaust. The results strongly suggests that local air quality measured in terms of the particulate-bound PAH burden could be significantly improved by the use of GTL kerosene either blended with or in place of Jet A-1 kerosene. PMID:22534092

Christie, Simon; Raper, David; Lee, David S; Williams, Paul I; Rye, Lucas; Blakey, Simon; Wilson, Chris W; Lobo, Prem; Hagen, Donald; Whitefield, Philip D

2012-06-01

366

Comparative analysis of monetary estimates of external environmental costs associated with combustion of fossil fuels  

SciTech Connect

Public utility commissions in a number of states have begun to explicitly treat costs of environmental externalities in the resource planning and acquisition process (Cohen et al. 1990). This paper compares ten different estimates and regulatory determinations of external environmental costs associated with fossil fuel combustion, using consistent assumptions about combustion efficiency, emissions factors, and resource costs. This consistent comparison is useful because it makes explicit the effects of various assumptions. This paper uses the results of the comparison to illustrate pitfalls in calculation of external environmental costs, and to derive lessons for design of policies to incorporate these externalities into resource planning. 38 refs., 2 figs., 10 tabs.

Koomey, J.

1990-07-01

367

Oxy-fuel combustion systems for pollution free coal fired power generation  

SciTech Connect

Jupiter Oxygen's patented oxy-fuel combustion systems1 are capable of economically generating power from coal with ultra-low emissions and increased boiler efficiency. Jupiter's system uses pure oxygen as the combustion agent, excluding air and thus nitrogen, concentrating CO2 and pollutants for efficient capture with near zero NOx production, reducing exhaust mass flow, and increasing radiant heat transfer. Flue-gas recirculation rates can be varied to add flexibility to new boiler designs using this technology. Computer modeling and thermal analysis have identified important design considerations in retrofit applications.

Ochs, Thomas L.; Oryshchyn, Danylo B.; Gross, Dietrich (Jupiter Oxygen Corp.); Patrick, Brian (Jupiter Oxygen Corp.); Gross, Alex (Jupiter Oxygen Corp.); Dogan, Cindy; Summers, Cathy A.; Simmons, William (CoalTeck LLC); Schoenfeld, Mark (Jupiter Oxygen Corp.)

2004-01-01

368

A fundamental study on the control of the HCCI combustion and emissions by fuel design concept combined with controllable EGR. Part 1. The basic characteristics of HCCI combustion  

Microsoft Academic Search

This article investigates the basic combustion parameters including start of the ignition timing, burn duration, cycle-to-cycle variation, and carbon monoxide (CO), unburned hydrocarbon (UHC), and nitric oxide (NOx) emissions of homogeneous charge compression ignition (HCCI) engines fueled with primary reference fuels (PRFs) and their mixtures. Two primary reference fuels, n-heptane and iso-octane, and their blends with RON25, RON50, RON75, and

Xing-Cai LŘ; Wei Chen; Zhen Huang

2005-01-01

369

Dynamics of hot spots in solid fuel combustion  

NASA Astrophysics Data System (ADS)

We consider the gasless combustion model of the SHS (self-propagating high temperature synthesis) process in which combustion waves are employed to synthesize desired materials. Specifically, we consider the combustion of a solid sample in which combustion occurs on the surface of a cylinder of radius R. We consider solution behavior as R is increased. This parameter is important for technological applications, as it is often desirable to synthesize large samples of the desired product. For the fixed value of the Zeldovich number considered, if R is sufficiently small, slowly propagating planar pulsating flames are the only modes observed. As R is increased transitions to more complex modes of combustion occur, including: (i) traveling waves (TWs), i.e., spin modes in which one or several symmetrically spaced hot spots rotate around the cylinder as the flame propagates along the cylindrical axis, thus following a helical path, (ii) counterpropagating (CP) modes, in which spots propagate in opposite angular directions around the cylinder, executing various types of dynamics, (iii) alternating spin CP (ASCP) modes, where rotation of a spot around the cylinder is interrupted by periodic events in which a new spot is spontaneously created ahead of the rotating spot. The new spot splits into CP daughter spots, one of which collides with the original spot leading to their eventual mutual annihilation, while the other continues to spin, (iv) modulated traveling waves (MTWs) consisting of either one or two symmetrically located rotating spots which exhibit a periodic modulation in speed and temperature as they rotate, (v) asymmetric traveling waves (ATWs) in which two spots of unequal strength and not separated by angle ?, rotate together as a bound state, (vi) modulated asymmetric traveling waves (MATWs) in which the two asymmetric spots oscillate in a periodic manner as they rotate, alternately approaching each other and then moving apart periodically in time, (vii) asymmetric ASCP (AASCP) modes in which a slowly varying bound state of two spots rotates around the cylinder with the leading spot, and subsequently the trailing spot, exhibiting episodes of ASCP behavior, and (viii) 3-headed spins in which three spots rotate around the cylinder in a nonuniform fashion so that each cell alternately approaches one of its neighbors and then the other. In one case, referred to as MTW3, the motion is apparently quasiperiodic, with neighboring spots approaching and departing from each other periodically in time as they rotate. In another case, referred to as C3, the motion is apparently chaotic. Two neighboring spots nearly collide, after which one spot is rapidly propelled away from the other as they rotate. Finally, for a slightly higher value of R, two neighboring spots collide, leading to annihilation of one spot and collapse of the 3-headed spin to a 2-headed spin mode.

Bayliss, A.; Matkowsky, B. J.; Aldushin, A. P.

2002-06-01

370

Method of regulating the amount of underfire air for combustion of wood fuels in spreader-stroke boilers  

DOEpatents

A method of metering underfire air for increasing efficiency and reducing particulate emissions from wood-fire, spreader-stoker boilers is disclosed. A portion of the combustion air, approximately one pound of air per pound of wood, is fed through the grate into the fuel bed, while the remainder of the combustion air is distributed above the fuel in the furnace, and the fuel bed is maintained at a depth sufficient to consume all oxygen admitted under fire and to insure a continuous layer of fresh fuel thereover to entrap charred particles inside the fuel bed.

Tuttle, Kenneth L. (Federal Way, WA)

1980-01-01

371

Flame tube parametric studies for control of fuel bound nitrogen using rich-lean two-stage combustion  

NASA Technical Reports Server (NTRS)

An experimental parametric study of rich-lean two-stage combustion in a flame tube is described and approaches for minimizing the conversion of fuel-bound nitrogen to nitrogen oxides in a premixed, homogeneous combustion system are evaluated. Air at 672 K and 0.48 MPa was premixed with fuel blends of propane, toluene, and pyridine at primary equivalence ratios ranging from 0.5 to 2.0 and secondary equivalence ratios of 0.5 to 0.7. Distillates of SRC-II, a coal syncrude, were also tested. The blended fuels were proportioned to vary fuel hydrogen composition from 9.0 to 18.3 weight percent and fuel nitrogen composition from zero to 1.5 weight percent. Rich-lean combustion proved effective in reducing fuel nitrogen to NO sub x conversion; conversion rates up to 10 times lower than those normally produced by single-stage combustion were achieved. The optimum primary equivalence ratio, where the least NO sub x was produced and combustion efficiency was acceptable, shifted between 1.4 and 1.7 with changes in fuel nitrogen content and fuel hydrogen content. Increasing levels of fuel nitrogen content lowered the conversion rate, but not enough to avoid higher NO sub x emissions as fuel nitrogen increased.

Schultz, D. F.; Wolfbrandt, G.

1980-01-01

372

Correlations of laminar combustion data for alternative SI engine fuels  

SciTech Connect

Most of the spark ignition engine cycle simulations use turbulent burning models which require a knowledge of laminar burning velocity of the fuel-air mixture as a function of mixture strength, unburned mixture temperature and pressure. Burning velocity data of different alternative spark ignition engine fuels obtained by various workers have been compared and critically evaluated. Empirical and semi-empirical correlations, suitable for cycle simulation studies, are presented for laminar burning velocity as a function of mixture strength, unburned mixture temperature, pressure, and residual gas fraction. Fuels considered include ethanol, methanol, alcohol/water blends, isooctane/alcohol blends, propane and isooctane. Experimental data obtained by the present author constitute the major part of the data used in correlations. Published data of other workers and the predictions of theoretical thermo-kinetic models have also been considered in correlations.

Gulder, O.L.

1984-01-01

373

Determination of alternative fuels combustion products: Phase 1 report  

SciTech Connect

This report describes the laboratory effort to identify and quantify organic exhaust species generated from alternative-fueled light-duty vehicles operating over the Federal Test Procedure on compressed natural gas, liquefied petroleum gas, methanol, ethanol, and reformulated gasoline. The exhaust species from these vehicles were identified and quantified for fuel/air equivalence ratios of 0.8, 1.0, and 1.2, nominally, and were analyzed with and without a vehicle catalyst in place to determine the influence of a catalytic converter on species formation.

Whitney, K.A. [Southwest Research Inst., San Antonio, TX (United States)

1997-09-01

374

Analysis of the combustion of four alternate fuels in a diesel engine using high speed photography: Final report  

Microsoft Academic Search

Ignition and combustion of four alternate fuels in a direct injected, two stroke, single cylinder diesel engine were investigated with high speed photography. The four fuels studies were: (1) Canadian 1990 Tar Sands fuel, (2) 57% Exxon Donor Solvent, (3) 100% Exxon Donor Solvent, and (4) neat methanol. Experimental results, obtained at half and full rack positions at 750 rpm,

D. L. Abata; D. Masterson

1989-01-01

375

Breakdown and Combustion of JP-10 Fuel Catalyzed by Nanoparticulate CeO2 and Fe2O3  

E-print Network

with JP-10, also affecting other liquid hydrocarbon fuels to varying extents, is that its ignition energy density material, coated with a thin shell of a catalyst that accelerates ignition and combustion, the catalyst-coated fuel particles will be injected into the combustor with the fuel and/or air and be consumed

Anderson, Scott L.

376

Combustion of biomass fuels in two cookstoves for their conservation  

Microsoft Academic Search

Conservation of biofuels is an urgent need of the present hour for reducing pressure on the natural forest resources and meeting the alternative requirements. In the present investigation a traditional biomass stove, presently used by 120 million households in India, and the Sugam-II stove, developed and dessiminated by TBU, IIT Delhi, were used for observing fuel utilization efficiency. Acacia nilotica

J. B. Kandpal; R. C. Maheshwari

1995-01-01

377

EMISSIONS ASSESSMENT FOR REFUSE-DERIVED FUEL COMBUSTION  

EPA Science Inventory

The RDF and coal were burned in a small spreader-stoker fired boiler. The parameters that were varied in this program were RDF type and amount of coal burned with the RDF. In two experiments a waste chemical, triethanolamine, was added to the fuel, and its destruction efficiency ...

378

Combustion aspects of the reapplication of energetic materials as fuels as a viable demil technology  

SciTech Connect

This investigation addresses the combustion-related aspects of the reapplication of energetic materials as fuels in boilers as an economically viable and environmentally acceptable use of excess energetic materials. The economics of this approach indicate that the revenues from power generation and chemical recovery approximately equal the costs of boiler modification and changes in operation. The primary tradeoff is the cost of desensitizing the fuels against the cost of open burn/open detonation (OB/OD) or other disposal techniques. Two principal combustion-related obstacles to the use of energetic-material-derived fuels are NO{sub x} generation and the behavior of metals. NO{sub x} measurements obtained in this investigation indicate that the nitrated components (nitrocellulose, nitroglycerin, etc.) of energetic materials decompose with NO{sub x} as the primary product. This can lead to high uncontrolled NO{sub x} levels (as high as 2,600 ppm on a 3% O{sub 2} basis for a 5% blend of energetic material in the fuel). NO{sub x} levels are sensitive to local stoichiometry and temperature. The observed trends resemble those common during the combustion of other nitrogen-containing fuels. Implications for NO{sub x} control strategies are discussed. The behavior of inorganic components in energetic materials tested in this investigation could lead to boiler maintenance problems such as deposition, grate failure, and bed agglomeration. The root cause of the problem is the potentially extreme temperature generated during metal combustion. Implications for furnace selection and operation are discussed.

Baxter, L.; Davis, K.; Sinquefield, S.; Huey, S.; Lipkin, J.; Shah, D.; Ross, J.; Sclippa, G. [Sandia National Labs., Livermore, CA (United States). Combustion Research Facility

1996-05-01

379

Fuel and physical properties of biodiesel components  

Technology Transfer Automated Retrieval System (TEKTRAN)

Biodiesel is an alternative diesel fuel derived from vegetable oils, animal fats or used oils. Specifically, biodiesel is the methyl or other alkyl esters of these oils or fats. Biodiesel also contains minor components such as free fatty acids and acylglycerols. Important fuel properties of biodi...

380

Thermal conductivity and combustion properties of wheat gluten foams.  

PubMed

Freeze-dried wheat gluten foams were evaluated with respect to their thermal and fire-retardant properties, which are important for insulation applications. The thermal properties were assessed by differential scanning calorimetry, the laser flash method and a hot plate method. The unplasticised foam showed a similar specific heat capacity, a lower thermal diffusivity and a slightly higher thermal conductivity than conventional rigid polystyrene and polyurethane insulation foams. Interestingly, the thermal conductivity was similar to that of closed cell polyethylene and glass-wool insulation materials. Cone calorimetry showed that, compared to a polyurethane foam, both unplasticised and glycerol-plasticised foams had a significantly longer time to ignition, a lower effective heat of combustion and a higher char content. Overall, the unplasticised foam showed better fire-proof properties than the plasticized foam. The UL 94 test revealed that the unplasticised foam did not drip (form droplets of low viscous material) and, although the burning times varied, self-extinguished after flame removal. To conclude both the insulation and fire-retardant properties were very promising for the wheat gluten foam. PMID:22332837

Blomfeldt, Thomas O J; Nilsson, Fritjof; Holgate, Tim; Xu, Jianxiao; Johansson, Eva; Hedenqvist, Mikael S

2012-03-01

381

Changes in combustion behavior of liquid fuels due to the addition of small amounts of ammonia borane or nano aluminum  

NASA Astrophysics Data System (ADS)

Both ammonia borane and nano aluminum as additives to liquid fuels are investigated. Both fundamental droplet combustion experiments and experiments using an unstable liquid rocket combustor are used to study the effects these additives on the combustion behavior. The liquid fuels consist of ethanol and JP-8. The droplet experiments consist of both visual and OH high speed planar laser-induced fluorescence measurements. Simple combustion models are incorporated as well to provide further understanding. It is found that ammonia borane increases the regression rate of a single ethanol droplet. Evidence indicates that hydrogen gas is released throughout the combustion process of the droplet and influences the combustion behavior notably. Laser diagnostics indicate that changes in flame structure occur. The other components of ammonia borane affect the combustion behavior of the droplet, especially near the end of the droplet lifetime, causing the droplet to shatter. Nano aluminum has very little impact on the combustion behavior of single fuel droplets of JP-8 and ethanol. Nano aluminum is observed to combust only when a surfactant, Neodol, is present which produces gas generation and bubble formation within the droplet. Combustor experiments show similar trends as the droplet combustion experiments. Ammonia borane has a notable impact on the combustion stability of the system allowing it to be unstable for more combustor geometries. It is shown that ammonia borane addition produces a bimodal unsteady energy release within the combustor while the neat fuel does not. This combustion behavior allows for the increased amount of unstable combustor geometries. Nano aluminum has a small impact on the combustion stability of the system causing pressure oscillations to increase.

Pfeil, Mark A.

382

Accelerating the Computation of Detailed Chemical Reaction Kinetics for Simulating Combustion of Complex Fuels  

SciTech Connect

Combustion of hydrocarbon fuels has been a very challenging scientific and engineering problem due to the complexity of turbulent flows and hydrocarbon reaction kinetics. There is an urgent need to develop an efficient modeling capability to accurately predict the combustion of complex fuels. Detailed chemical kinetic models for the surrogates of fuels such as gasoline, diesel and JP-8 consist of thousands of chemical species and Arrhenius reaction steps. Oxygenated fuels such as bio-fuels and heavier hydrocarbons, such as from newer fossil fuel sources, are expected to have a much more complex chemistry requiring increasingly larger chemical kinetic models. Such models are beyond current computational capability, except for homogeneous or partially stirred reactor type calculations. The advent of highly parallel multi-core processors and graphical processing units (GPUs) promises a steep increase in computational performance in the coming years. This paper will present a software framework that translates the detailed chemical kinetic models to high- performance code targeted for GPU accelerators.

Grout, Ray W [ORNL

2012-01-01

383

A synthesis of carbon dioxide emissions from fossil-fuel combustion  

SciTech Connect

This synthesis discusses the emissions of carbon dioxide from fossil-fuel combustion and cement production. While much is known about these emissions, there is still much that is unknown about the details surrounding these emissions. This synthesis explores 5 our knowledge of these emissions in terms of why there is concern about them; how they are calculated; the major global efforts on inventorying them; their global, regional, and national totals at different spatial and temporal scales; how they are distributed on global grids (i.e. maps); how they are transported in models; and the uncertainties associated with these different aspects of the emissions. The magnitude of emissions 10 from the combustion of fossil fuels has been almost continuously increasing with time since fossil fuels were first used by humans. Despite events in some nations specifically designed to reduce emissions, or which have had emissions reduction as a byproduct of other events, global total emissions continue their general increase with time. Global total fossil-fuel carbon dioxide emissions are known to within 10% uncertainty (95% 15 confidence interval). Uncertainty on individual national total fossil-fuel carbon dioxide emissions range from a few percent to more than 50 %. The information discussed in this manuscript synthesizes global, regional and national fossil-fuel carbon dioxide emissions, their distributions, their transport, and the associated uncertainties.

Andres, Robert Joseph [ORNL; Boden, Thomas A [ORNL; Breon, F.-M. [CEA/DSM/LSCE, Gif sur Yvette, France; Ciais, P. [LSCE/CEA, Gif-sur-Yvette, France; Davis, S. [Carnegie Institution of Washington; Erickson, D [Oak Ridge National Laboratory (ORNL); Gregg, J. S. [Riso National Laboratory, Roskilde, Denmark; Jacobson, Andrew [NOAA ESRL and CIRES; Marland, Gregg [Appalachian State University; Miller, J. [NOAA ESRL and CIRES; Oda, T [NOAA ESRL/Boulder, CO/Cooperative Institute for Research in the Atmosphere, Colorado State Univ.; Oliver, J. G. J. [PBL Netherlands Environmental Assessment Agency, Bilthoven, The Netherlands; Raupach, Michael [CSIRO Marine and Atmospheric Research; Rayner, P [University of Melbourne, Australia; Treanton, K. [Energy Statistics Division, International Energy Agency, Paris, France

2012-01-01

384

Accelerating the Computation of Detailed Chemical Reaction Kinetics for Simulating Combustion of Complex Fuels  

SciTech Connect

Combustion of hydrocarbon fuels has been a very challenging scientific and engineering problem due to the complexity of turbulent flows and hydrocarbon reaction kinetics. There is an urgent need to develop an efficient modeling capability to accurately predict the combustion of complex fuels. Detailed chemical kinetic models for the surrogates of fuels such as gasoline, diesel and JP-8 consist of thousands of chemical species and Arrhenius reaction steps. Oxygenated fuels such as bio-fuels and heavier hydrocarbons, such as from newer fossil fuel sources, are expected to have a much more complex chemistry requiring increasingly larger chemical kinetic models. Such models are beyond current computational capability, except for homogeneous or partially stirred reactor type calculations. The advent of highly parallel multi-core processors and graphical processing units (GPUs) promises a steep increase in computational performance in the coming years. This paper will present a software framework that translates the detailed chemical kinetic models to high-performance code targeted for GPU accelerators.

Sankaran, R.; Grout, R.

2012-01-01

385

Stabilization of liquid hydrocarbon fuel combustion by using a programmable microwave discharge in a subsonic airflow  

SciTech Connect

Under conditions of a programmable discharge (a surface microwave discharge combined with a dc discharge), plasma-enhanced combustion of alcohol injected into a subsonic (M = 0.3-0.9) airflow in the drop (spray) phase is stabilized. It is shown that the appearance of the discharge, its current-voltage characteristic, the emission spectrum, the total emission intensity, the heat flux, the electron density, the hydroxyl emission intensity, and the time dependences of the discharge current and especially discharge voltage change substantially during the transition from the airflow discharge to stabilized combustion of the liquid hydrocarbon fuel. After combustion stabilization, more than 80% of liquid alcohol can burn out, depending on the input power, and the flame temperature reaches {approx}2000 K.

Kopyl, P. V.; Surkont, O. S.; Shibkov, V. M.; Shibkova, L. V. [Moscow State University, Faculty of Physics (Russian Federation)

2012-06-15

386

Analytical evaluation of effect of equivalence ratio inlet-air temperature and combustion pressure on performance of several possible ram-jet fuels  

NASA Technical Reports Server (NTRS)

The results of an analytical investigation of the theoretical air specific impulse performance and adiabatic combustion temperatures of several possible ram-jet fuels over a range of equivalence ratios, inlet-air temperatures, and combustion pressures, is presented herein. The fuels include octane-1, 50-percent-magnesium slurry, boron, pentaborane, diborane, hydrogen, carbon, and aluminum. Thermal effects from high combustion temperatures were found to effect considerably the combustion performance of all the fuels. An increase in combustion pressure was beneficial to air specific impulse at high combustion temperatures. The use of these theoretical data in engine operation and in the evaluation of experimental data is described.

Tower, Leonard K; Gammon, Benson E

1953-01-01

387

Fluidized bed combustion of pelletized biomass and waste-derived fuels  

SciTech Connect

The fluidized bed combustion of three pelletized biogenic fuels (sewage sludge, wood, and straw) has been investigated with a combination of experimental techniques. The fuels have been characterized from the standpoints of patterns and rates of fuel devolatilization and char burnout, extent of attrition and fragmentation, and their relevance to the fuel particle size distribution and the amount and size distribution of primary ash particles. Results highlight differences and similarities among the three fuels tested. The fuels were all characterized by limited primary fragmentation and relatively long devolatilization times, as compared with the time scale of particle dispersion away from the fuel feeding ports in practical FBC. Both features are favorable to effective lateral distribution of volatile matter across the combustor cross section. The three fuels exhibited distinctively different char conversion patterns. The high-ash pelletized sludge burned according to the shrinking core conversion pattern with negligible occurrence of secondary fragmentation. The low-ash pelletized wood burned according to the shrinking particle conversion pattern with extensive occurrence of secondary fragmentation. The medium-ash pelletized straw yielded char particles with a hollow structure, resembling big cenospheres, characterized by a coherent inorganic outer layer strong enough to prevent particle fragmentation. Inert bed particles were permanently attached to the hollow pellets as they were incorporated into ash melts. Carbon elutriation rates were very small for all the fuels tested. For pelletized sludge and straw, this was mostly due to the shielding effect of the coherent ash skeleton. For the wood pellet, carbon attrition was extensive, but was largely counterbalanced by effective afterburning due to the large intrinsic reactivity of attrited char fines. The impact of carbon attrition on combustion efficiency was negligible for all the fuels tested. The size distribution of primary ash particles liberated upon complete carbon burnoff largely reflected the combustion pattern of each fuel. Primary ash particles of size nearly equal to that of the parent fuel were generated upon complete burnoff of the pelletized sludge. Nonetheless, secondary attrition of primary ash from pelletized sludge is large, to the point where generation of fine ash would be extensive over the typical residence time of bed ash in fluidized bed combustors. Very few and relatively fine primary ash particles were released after complete burnoff of wood pellets. Primary ash particles remaining after complete burnoff of pelletized straw had sizes and shapes that were largely controlled by the occurrence of ash agglomeration phenomena. (author)

Chirone, R.; Scala, F.; Solimene, R. [Istituto di Ricerche sulla Combustione - C.N.R., Piazzale V. Tecchio 80, 80125 Naples (Italy); Salatino, P.; Urciuolo, M. [Dipartimento di Ingegneria Chimica - Universita degli Studi di Napoli Federico II, Piazzale V. Tecchio 80, 80125 Naples (Italy)

2008-10-15

388

Combustion of fat and vegetable oil derived fuels in diesel engines  

Microsoft Academic Search

In this article, the status of fat and oil derived diesel fuels with respect to fuel properties, engine performance, and emissions is reviewed. The fuels considered are primarily the methyl esters of fatty acids derived from a variety of vegetable oils and animal fats, and referred to as biodiesel. The major obstacle to widespread use of biodiesel is the high

Michael S. Graboski; Robert L. McCormick

1998-01-01

389

Determination of performance and combustion characteristics of a diesel engine fueled with canola and waste palm oil methyl esters  

Microsoft Academic Search

In this study, the performance, combustion and injection characteristics of a direct injection diesel engine have been investigated experimentally when it was fueled with canola oil methyl ester (COME) and waste (frying) palm oil methyl ester (WPOME). In order to determine the performance and combustion characteristics, the experiments were conducted at constant engine speeds under the full load condition of

Ahmet Necati Ozsezen; Mustafa Canakci

2011-01-01

390

Development of an integrated reduced fuel oxidation and soot precursor formation mechanism for CFD simulations of diesel combustion  

Microsoft Academic Search

In this reported work, a reduced chemical mechanism of surrogate diesel fuel was developed for diesel engine simulations. The aim here was to employ an appropriate reduction scheme to create a compact yet sufficiently comprehensive model which can accurately account for in-cylinder diesel combustion and soot precursor formation processes. The Combustion Engine Research Center (CERC) mechanism of Chalmers University of

Kar Mun Pang; Hoon Kiat Ng; Suyin Gan

2011-01-01

391

Trace elements found in the fuel and in-furnace fine particles collected from 80MW BFB combusting solid recovered fuel  

Microsoft Academic Search

The main fine particle (dp<1?m) forming elements found in combustion gases of anthropogenic waste or biomass fired boilers are typically K, Na and Cl, possibly complemented with S. When these are excluded, in solid recovered fuel (SRF) combustion the main elements were found to be: Ba, Br, Cr, Cu, Fe, Pb, Sb, Sn and Zn. Fine particle composition is presented

P. Vainikka; D. Lindberg; A. Moilanen; H. Ollila; M. Tiainen; J. Silvennoinen; M. Hupa

392

Achieve Continuous Injection of Solid Fuels into Advanced Combustion System Pressures  

SciTech Connect

The overall objective of this project is the development of a mechanical rotary-disk feeder, known as the Stamet Posimetric High Pressure Solids Feeder System, to feed dry granular coal continuously and controllably into pressurized environments of up to 35 kg/cm{sup 2} (500 psi). This was to be accomplished in two phases. The first task was to review materials handling experience in pressurized operations as it related to the target pressures for this project, and review existing coal preparation processes and specifications currently used in advanced combustion systems. Samples of existing fuel materials were obtained and tested to evaluate flow, sealing and friction properties. This provided input data for use in the design of the Stamet Feeders for the project, and ensured that the material specification used met the requirements of advanced combustion & gasification systems. Ultimately, Powder River Basin coal provided by the PSDF facility in Wilsonville, AL was used as the basis for the feeder design and test program. Based on the material property information, a Phase 1 feeder system was designed and built to accomplish feeding the coal to an intermediate pressure up to 21 kg/cm{sup 2} (300 psi) at feed rates of approximately 100 kilograms (220lbs) per hour. The pump & motor system was installed in a custom built test rig comprising an inlet vessel containing an active live-wall hopper mounted in a support frame, transition into the pump inlet, transition from pump outlet and a receiver vessel containing a receiver drum supported on weigh cells. All pressure containment on the rig was rated for the final pressure requirement of 35 kg/cm{sup 2} (500psi). A program of testing and modification was carried out in Stamet's facility in CA, culminating in successful feeding of coal into the Phase 1 target of 21 kg/cm{sup 2} (300psi) gas pressure in December 2003. Further testing was carried out at CQ Inc's facility in PA, providing longer run times and experience of handling and feeding the coal in winter conditions. Based on the data developed through the testing of the Phase I unit, a Phase II system was designed for feeding coal into pressures of up to 35 kg/cm{sup 2} (500 psi). A further program of testing and modification was then carried out in Stamet's facility, with the target pressure being achieved in January 2005. Repeated runs at pressure were achieved, and optimization of the machine resulted in power reductions of 60% from the first successful pressure runs. General design layout of a commercial-scale unit was conducted, and preliminary cost estimates for a commercial unit obtained.

Derek L. Aldred; Timothy Saunders

2005-07-01

393

Design and implementation of Carbon Monoxide and Oxygen emissions measurement in swirl-stabilized oxy-fuel combustion  

E-print Network

Oxy-fuel combustion in natural gas power generation is a technology of growing interest as it provides the most efficient means of carbon capture. Since all the emissions from these power plants are sequestered, there are ...

Sommer, Andrew (Andrew Zhang)

2013-01-01

394

Theoretical and experimental studies on the combustion of synthetic fuels in spark ignition engines  

SciTech Connect

The incentives for studying the combustion of alternative fuels in engines are, some fuel as fuel additive may solve the problem of emissions, knock, derivability and efficiency. Also an alternative fuel may help conserve the world's petroleum supplies as well as being available when those supplies are exhausted. Transportation is unique among the energy consuming sectors of the economy of industrialized nations, because it is totally dependent on one source of fuel crude oil. It has therefore imparative to investigate the consequences of using non-petroleum fuels for transportation application. Alcohol has been proposed as a clean-burning synthetic fuel, that could have many applications, and its advantages have been widely acclaimed. Two routes exits to introduce alcohol as a fuel into the transportation system. First route, is the mixing of alcohol with lead-free gasoline in concentration up to 20% by volume, and the resulting blend be used as fuel for existing cars without engine modifications. In the second route, pure alcohol can be used in cars that have been appropriately modified. Both routes will be discussed in this paper.

Desoky, A.A.; El-Eman, S.M.

1983-12-01

395

Laboratory characterization of PM emissions from combustion of wildland biomass fuels  

NASA Astrophysics Data System (ADS)

Particle emissions from open burning of southwestern (SW) and southeastern (SE) U.S. fuel types during 77 controlled laboratory burns are presented. The fuels include SW vegetation types: ceanothus, chamise/scrub oak, coastal sage scrub, California sagebrush, manzanita, maritime chaparral, masticated mesquite, oak savanna, and oak woodland, as well as SE vegetation types: 1 year, 2 year rough, pocosin, chipped understory, understory hardwood, and pine litter. The SW fuels burned at higher modified combustion efficiency (MCE) than the SE fuels resulting in lower particulate matter mass emission factor. Particle mass distributions for six fuels and particle number emission for all fuels are reported. Excellent mass closure (slope = 1.00, r2 = 0.94) between ions, metals, and carbon with total weight was obtained. Organic carbon emission factors inversely correlated (R2 = 0.72) with average MCE, while elemental carbon (EC) had little correlation with average MCE (R2 = 0.10). The EC/total carbon ratio sharply increased with MCE for MCEs exceeding 0.94. The average levoglucosan and total polycyclic aromatic hydrocarbon (PAH) emissions factors ranged from 25 to 1272 mg/kg fuel and 1.8 to 11.3 mg/kg fuel, respectively. No correlation between average MCE and emissions of PAHs/levoglucosan was found. Additionally, PAH diagnostic ratios were observed to be poor indicators of biomass burning. Large fuel type and regional dependency were observed in the emission rates of ammonium, nitrate, chloride, sodium, and potassium.

Hosseini, S.; Urbanski, S. P.; Dixit, P.; Qi, L.; Burling, I. R.; Yokelson, R. J.; Johnson, T. J.; Shrivastava, M.; Jung, H. S.; Weise, D. R.; Miller, J. W.; Cocker, D. R.

2013-09-01

396

Experimental Investigation of Fuel-Reactivity Controlled Compression Ignition (RCCI) Combustion Mode in a Multi-Cylinder, Light-Duty Diesel Engine  

SciTech Connect

An experimental study was performed to provide the combustion and emission characteristics resulting from fuel-reactivity controlled compression ignition (RCCI) combustion mode utilizing dual-fuel approach in a light-duty, multi-cylinder diesel engine. In-cylinder fuel blending using port fuel injection of gasoline before intake valve opening (IVO) and early-cycle, direct injection of diesel fuel was used as the charge preparation and fuel blending strategy. In order to achieve the desired auto-ignition quality through the stratification of the fuel-air equivalence ratio ( ), blends of commercially available gasoline and diesel fuel were used. Engine experiments were performed at an engine speed of 2300rpm and an engine load of 4.3bar brake mean effective pressure (BMEP). It was found that significant reduction in both nitrogen oxide (NOx) and particulate matter (PM) was realized successfully through the RCCI combustion mode even without applying exhaust gas recirculation (EGR). However, high carbon monoxide (CO) and hydrocarbon (HC) emissions were observed. The low combustion gas temperature during the expansion and exhaust processes seemed to be the dominant source of high CO emissions in the RCCI combustion mode. The high HC emissions during the RCCI combustion mode could be due to the increased combustion quenching layer thickness as well as the -stratification at the periphery of the combustion chamber. The slightly higher brake thermal efficiency (BTE) of the RCCI combustion mode was observed than the other combustion modes, such as the conventional diesel combustion (CDC) mode, and single-fuel, premixed charge compression ignition (PCCI) combustion mode. The parametric study of the RCCI combustion mode revealed that the combustion phasing and/or the peak cylinder pressure rise rate of the RCCI combustion mode could be controlled by several physical parameters premixed ratio (rp), intake swirl intensity, and start of injection (SOI) timing of directly injected fuel unlike other low temperature combustion (LTC) strategies.

Cho, Kukwon [ORNL] [ORNL; Curran, Scott [ORNL] [ORNL; Prikhodko, Vitaly Y [ORNL] [ORNL; Sluder, Scott [ORNL] [ORNL; Parks, II, James E [ORNL; Wagner, Robert M [ORNL] [ORNL

2011-01-01

397

Experimental Study of the Combustion Dynamics of Renewable & Fossil Fuel Co-Fire in Swirling Flame  

NASA Astrophysics Data System (ADS)

The complex experimental research into the combustion dynamics of rene-wable (wood biomass) and fossil (propane) fuel co-fire in a swirling flame flow has been carried out with the aim to achieve clean and effective heat production with reduced carbon emissions. The effect of propane co-fire on the formation of the swirling flame velocity, temperature and composition fields as well as on the combustion efficiency and heat output has been analysed. The results of experimental study show that the propane supply into the wood biomass gasifier provides faster wood fuel gasification with active release of volatiles at the primary stage of swirling flame flow formation, while the swirl-induced recirculation with enhanced mixing of the flame components results in a more complete burnout of wood volatiles downstream of the combustor with reduced mass fraction of polluting impurities in the emissions.

Za?e, M.; Barmina, I.; KriÜko, V.; Gedrovi?s, M.; Desc?ickis, A.

2009-01-01

398

Fuel-rich solid propellant boron combustion. Final report, 1 April 1982-31 March 1983  

SciTech Connect

A unified single boron particle ignition/combustion/ extinguishment model capable of treating the effects of various oxidizers, Finite-rate kinetics, and time-dependent environmental conditions has been developed and successfully checked against historical data bases. In addition, parts of this model have been combined with enthalpy and species conservation equations for analysis of boron combustion efficiency in an idealized slurry ramjet combustor (perfectly stirred reactor followed by a series of incremental plug-flow reactors with arbitrary air addition as a function of operational and design parameters). Cibsuderabke subgke particle ignition/combustion data have been obtained over a wide range of particle sizes (5-70 Microns) in wet atmospheres with this experimental effort currently being extended to dry atmospheres. An experiment to determine the kinetics of the boron oxide-water reaction (crucial to ignition) is in progress. A laboratory apparatus for studying combustion of highly-boron-loaded solid fuel ramjet grains in hot air crossflow on a fundamental basis has been completed. Design of a well-stirred reactor for study of boron cloud and slurry combustion is complete and equipment fabrication is underway.

King, M.K.; Komar, J.; Fry, R.S.

1983-05-31

399

Device for admitting exhaust gases and fuel-air mixtures into the cylinders of an internal combustion engine  

Microsoft Academic Search

A device is proposed for the supply of operating air-fuel mixtures including exhaust gases to internal combustion engines. Between the opening periods of the inlet valves of an internal combustion engine, precisely dispensed quantities of recirculated exhaust gas are pre-stored in the intake channel directly upstream of the inlet valve whereby a stratification of exhaust gas and fuel-air mixture in

K. Eckert; H. Britsch; E. Linder; K. Muller; W. Polach

1984-01-01

400

Combustion heat release analysis of ethanol or n-butanol diesel fuel blends in heavy-duty DI diesel engine  

Microsoft Academic Search

An experimental study is conducted to evaluate the effects of using blends of diesel fuel with either ethanol in proportions of 5% and 10% or n-butanol in 8% and 16% (by vol.), on the combustion behavior of a fully-instrumented, six-cylinder, turbocharged and after-cooled, heavy duty, direct injection (DI), ĹMercedes-Benzĺ engine installed at the authorsĺ laboratory. Combustion chamber and fuel injection

D. C. Rakopoulos; C. D. Rakopoulos; R. G. Papagiannakis; D. C. Kyritsis

2011-01-01

401

Integration of Evaporative Gas Turbine with Oxy-Fuel Combustion for Carbon Dioxide Capture  

Microsoft Academic Search

This paper studied the integration of Evaporative Gas Turbine (EvGT) cycle with oxy-fuel combustion for CO2 capture. The impact of key parameters on system electrical efficiency, such as the oxygen purity, Water\\/Gas ratio (W\\/G) has been investigated concerning thermal efficiency. The performance of dry recycle and wet recycle also has be analyzed and compared. Simulation results shows that: (1) 97%

Y. Hu; H. Li; J. Yan

2010-01-01

402

What is the fate of CO2 produced by fossil fuel combustion?  

NSDL National Science Digital Library

Students consider why the observed atmospheric CO2 increase rate is only ~60% of the CO2 loading rate due to fossil fuel combustion. They develop a box-model to simulate the atmospheric CO2 increase during the industrial era and compare it to the historic observations of atmospheric CO2 concentrations. The model is then used to forecast future concentrations of atmospheric CO2 during the next century.

Paul Quay

403

Kinetic processes in the plasma formed in combustion of hydrocarbon fuels  

Microsoft Academic Search

An analysis of the basic kinetic processes responsible for the formation of ions, electrons, charged and neutral carbon clusters\\u000a and particles of nanometer size in the combustion of hydrocarbon fuels has been made. It has been shown that the formation\\u000a of a polydisperse ensemble of positively and negatively charged particles is mainly caused by the ion adhesion to primary\\u000a particles

A. M. Starik; A. M. Savelĺev; N. S. Titova

2011-01-01

404

40 CFR 1065.120 - Fuel properties and fuel temperature and pressure.  

Code of Federal Regulations, 2012 CFR

...2012-07-01 false Fuel properties and fuel temperature and pressure. 1065.120 Section...1065.120 Fuel properties and fuel temperature and pressure. (a) Use fuels...the engine manufacturer specifies fuel temperature and pressure tolerances and the...

2012-07-01

405

40 CFR 1065.120 - Fuel properties and fuel temperature and pressure.  

Code of Federal Regulations, 2011 CFR

...2011-07-01 false Fuel properties and fuel temperature and pressure. 1065.120 Section...1065.120 Fuel properties and fuel temperature and pressure. (a) Use fuels...the engine manufacturer specifies fuel temperature and pressure tolerances and the...

2011-07-01

406

40 CFR 1065.120 - Fuel properties and fuel temperature and pressure.  

Code of Federal Regulations, 2013 CFR

...2013-07-01 false Fuel properties and fuel temperature and pressure. 1065.120 Section...1065.120 Fuel properties and fuel temperature and pressure. (a) Use fuels...the engine manufacturer specifies fuel temperature and pressure tolerances and the...

2013-07-01

407

40 CFR 1065.120 - Fuel properties and fuel temperature and pressure.  

Code of Federal Regulations, 2010 CFR

...2010-07-01 false Fuel properties and fuel temperature and pressure. 1065.120 Section...1065.120 Fuel properties and fuel temperature and pressure. (a) Use fuels...the engine manufacturer specifies fuel temperature and pressure tolerances and the...

2010-07-01

408

Structural and magnetic properties of barium hexaferrite nanostructured particles prepared by the combustion method  

NASA Astrophysics Data System (ADS)

The combustion method, a fast and simple way of preparing sub-micrometer sized particles from a solution of the corresponding metal nitrates and a reducing agent (ODH, TFTA) which is used as a fuel, was adapted to the synthesis of barium hexaferrite particles. Structural and magnetic properties were investigated by X-ray diffraction, transmission electronic microscopy, magnetic measurements and M÷ssbauer spectrometry on nanostructured as well as on microstructured particles resulting from annealing treatments under different conditions. High values of the coercive field (5.3 kOe) and of the magnetization (57.8 emu/g), at 13.5 kOe, were obtained on well crystallized BaFe12O19 particles annealed at 850░C.

Castro, S.; Gayoso, M.; Rivas, J.; Greneche, J. M.; Mira, J.; RodrÝguez, C.

1996-01-01

409

Smoldering combustion propagation through a permeable horizontal fuel layer  

SciTech Connect

Although the propagation rate of smoldering through porous horizontal fuel layers has been measured for a variety of materials, there has been little work on the structure of the smolder reaction zone and the factors controlling it. These latter aspects are the focus for this paper for the case of thick (18 cm) layers of wood-based fibers in the form of cellulosic insulation smoldering under natural convection air supply conditions. Two-dimensional profiles of temperature, oxygen mole fraction, and residual organic material have been measured both for unretarded insulation and for insulation having 25 wt% of the smolder retardant, boric acid, added on.

Ohlemiller, T.J. (Center for Fire Research, National Institute of Standards and Technology, Gaithersburg, MD (US))

1990-09-01

410

Combined catalysts for the combustion of fuel in gas turbines  

DOEpatents

A catalytic oxidation module for a catalytic combustor of a gas turbine engine is provided. The catalytic oxidation module comprises a plurality of spaced apart catalytic elements for receiving a fuel-air mixture over a surface of the catalytic elements. The plurality of catalytic elements includes at least one primary catalytic element comprising a monometallic catalyst and secondary catalytic elements adjacent the primary catalytic element comprising a multi-component catalyst. Ignition of the monometallic catalyst of the primary catalytic element is effective to rapidly increase a temperature within the catalytic oxidation module to a degree sufficient to ignite the multi-component catalyst.

Anoshkina, Elvira V.; Laster, Walter R.

2012-11-13

411

Combustion and emissions characterization of pelletized coal fuels. [Quarterly] technical report, March 1--May 31, 1993  

SciTech Connect

Pelletization of coal offers a means of utilizing coal fines which otherwise would be difficult to use. Other advantages of coal pelletization include: (a) utilization of low grade fuels such as preparation plant waste, (b) impregnation of pellets with calcium carbonate or calcium hydroxide sorbent for efficient sulfur removal, and (c) utilization of coal fines of low quality in combination with different types of binders. The objective of this project is to investigate the carbon conversion efficiency and SO{sub 2} and NO{sub x} emissions from combusting pelletized coal fuels made from preparation plant waste streams using both limestone and calcium hydroxide as sorbent and cornstarch and gasification tar as binders. The combustion performance of these pelletized fuels is compared with equivalent data from a reference run-of-mine coal. Six different samples of coal pellets have been secured from ISGS researchers. Combustion and emissions characterization of these pellets in the laboratory scale 4-inch diameter circulating fluidized bed have been performed on some of the pellet samples. The pellets burn readily, and provide good bed temperature control. Preliminary results show good carbon conversion efficiencies. Oxides of nitrogen emissions are quite low and sulfur dioxide emissions are as good as or lower than those from a representative run-of-mine coal.

Rajan, S. [Southern Illinois Univ., Carbondale, IL (United States). Dept. of Mechanical Engineering and Energy Processes

1993-09-01

412

Combustion-derived nanoparticle exposure and household solid fuel use in Xuanwei and Fuyuan, China  

PubMed Central

Combustion-derived nanoparticles (CDNPs) have not been readably measurable until recently. We conducted a pilot study to determine CDNP levels during solid fuel burning. The aggregate surface area of CDNP (?m2/cm3) was monitored continuously in 15 Chinese homes using varying fuel types (i.e. bituminous coal, anthracite coal, wood) and stove types (i.e. portable stoves, stoves with chimneys, firepits). Information on fuel burning activities was collected and PM2.5 levels were measured. Substantial exposure differences were observed during solid fuel burning (mean: 228.1 ?m2/cm3) compared to times without combustion (mean: 14.0 ?m2/cm3). The observed levels during burning were reduced by about four-fold in homes with a chimney (mean: 92.1 ?m2/cm3; n = 9), and effects were present for all fuel types. Each homeĺs CDNP measurement was only moderately correlated with the respective PM2.5 measurements (r2 = 0.43; p = 0.11). Our results indicate that household coal and wood burning contributes to indoor nanoparticle levels, which are not fully reflected in PM2.5 measurements. PMID:22639822

Hosgood, H. Dean; Lan, Qing; Vermeulen, Roel; Wei, Hu; Reiss, Boris; Coble, Joseph; Wei, Fusheng; Jun, Xu; Wu, Guoping; Rothman, Nat

2014-01-01

413

Combustion-derived nanoparticle exposure and household solid fuel use in Xuanwei and Fuyuan, China.  

PubMed

Combustion-derived nanoparticles (CDNPs) have not been readably measurable until recently. We conducted a pilot study to determine CDNP levels during solid fuel burning. The aggregate surface area of CDNP (?m(2)/cm(3)) was monitored continuously in 15 Chinese homes using varying fuel types (i.e. bituminous coal, anthracite coal, wood) and stove types (i.e. portable stoves, stoves with chimneys, firepits). Information on fuel burning activities was collected and PM(2.5) levels were measured. Substantial exposure differences were observed during solid fuel burning (mean: 228.1 ?m(2)/cm(3)) compared to times without combustion (mean: 14.0 ?m(2)/cm(3)). The observed levels during burning were reduced by about four-fold in homes with a chimney (mean: 92.1 ?m(2)/cm(3); n = 9), and effects were present for all fuel types. Each home's CDNP measurement was only moderately correlated with the respective PM(2.5) measurements (r (2) = 0.43; p = 0.11). Our results indicate that household coal and wood burning contributes to indoor nanoparticle levels, which are not fully reflected in PM(2.5) measurements. PMID:22639822

Hosgood, H Dean; Vermeulen, Roel; Wei, Hu; Reiss, Boris; Coble, Joseph; Wei, Fusheng; Jun, Xu; Wu, Guoping; Rothman, Nat; Lan, Qing

2012-01-01

414

Fuel-Specific Effect of Exhaust Gas Residuals on HCCI Combustion: A Modeling Study  

SciTech Connect

A modeling study was performed to investigate fuel-specific effects of exhaust gas recirculation (EGR) components on homogeneous charge compression ignition (HCCI) combustion at conditions relevant to the negative valve overlap (NVO) strategy using CHEMKIN-PRO. Four single-component fuels with well-established kinetic models were chosen: n-heptane, iso-octane, ethanol, and toluene. These fuels were chosen because they span a wide range of fuel chemistries, and produce a wide compositions range of complete stoichiometric products (CSP). The simulated engine conditions combined a typical spark ignition engine compression ratio (11.34) and high intake charge temperatures (500-550 K) that are relevant to NVO HCCI. It was found that over the conditions investigated, all the fuels had overlapping start of combustion (SOC) phasing, despite the wide range in octane number (RON = 0 to 120). The effect of the EGR components CO2 and H2O was to suppress the compression temperature because of their higher heat capacities, which retarded SOC. For a concentration of O2 higher than the stoichiometric amount, or excess O2, there was an effect of advancing SOC for n-heptane, iso-octane, and toluene, but SOC for ethanol was not advanced. Low temperature heat release (LTHR) for n-heptane was also found to be highly dependent on excess O2, and mild endothermic reaction was observed for cases when excess O2 was not present.

Szybist, James P [ORNL

2008-01-01

415

Hydrocarbon-fuel/combustion-chamber-liner materials compatibility. Interim final report, 7 November 1986-31 October 1989  

SciTech Connect

Results of material compatibility experiments using hydrocarbon fuels in contact with copper-based combustion chamber liner materials are presented. Mil-Spec RP-1, n- dodecane, propane, and methane fuels were tested in contact with OFHC, NASA-Z, and ZrCu coppers. Two distinct test methods were employed. Static tests, in which copper coupons were exposed to fuel for long durations at constant temperature and pressure, provided compatibility data in a precisely controlled environment. Dynamic tests, using the Aerojet Carbothermal Test Facility, provided fuel and copper compatibility data under realistic booster engine service conditions. Tests were conducted using very pure grades of each fuel and fuels to which a contaminant, e.g., ethylene or methyl mercaptan, was added to define the role played by fuel impurities. Conclusions are reached as to degradation mechanisms and effects, methods for the elimination of these mechanisms, selection of copper alloy combustion chamber liners, and hydrocarbon fuel purchase specifications.

Gage, M.L.

1990-04-01

416

Combustion  

NSDL National Science Digital Library

In this chemistry activity, learners discover that the weight of the product of combustion is greater than that of the starting material. Learners will compare the weight of steel wool before and after it is heated. Learners are asked to consider why the steel wool weighs more (oxidation) as well as write the balanced chemical equation for the burning of steel. This activity uses an open flame; adult supervision is recommended. The resource includes notes for educators and extension ideas.

2014-01-28

417

Effect of fuel properties on the first cycle fuel delivery in a Port Fuel Injected Spark Ignition Engine  

E-print Network

Achieving robust combustion while also yielding low hydrocarbon (HC) emissions is difficult for the first cycle of cranking during the cold start of a Port Fuel Injected (PFI) Spark Ignition (SI) engine. Cold intake port ...

Lang, Kevin R., 1980-

2004-01-01

418

A study on low NO{sub x} combustion in LBG-fueled 1500 C-class gas turbine  

SciTech Connect

Developing integrated coal gasification combined-cycle systems ensures cost-effective and environmentally sound options for supplying future power generation needs. The reduction of NO{sub x} emissions and increasing the inlet temperature of gas turbines are the most significant issues in gas turbine development in Integrated Coal Gasification Combined Cycle (IGCC) power generation systems. The coal gasified fuel, which is produced in a coal gasifier of an air-blown entrained-flow type has a calorific value as low as 1/10 of natural gas. Furthermore, the fuel gas contains ammonia when a gas cleaning system is a hot type, and ammonia will be converted to nitrogen oxides in the combustion process of a gas turbine. This study is performed in a 1,500 C-class gas turbine combustor firing low-Btu coal-gasified fuel in IGCC systems. An advanced rich-lean combustor of 150-MW class gas turbine was designed to hold stable combustion burning low-Btu gas and to reduce fuel NO{sub x} emissions from the ammonia in the fuel. The main fuel and the combustion air are supplied into a fuel-rich combustion chamber with strong swirl flow and make fuel-rich flame to decompose ammonia into intermediate reactants such as NHi and HCN. The secondary air is mixed with primary combustion gas dilatorily to suppress the oxidation of ammonia reactants in fuel-lean combustion chamber and to promote a reducing process to nitrogen. By testing under atmospheric pressure conditions, the authors have obtained a very significant result through investigating the effect of combustor exit gas temperature on combustion characteristics. Since they have ascertained the excellent performance of the tested combustor through their extensive investigation, they wish to report on the results.

Nakata, T. [Tohoku Univ., Sendai, Miyagi (Japan). Dept. of Aeronautics and Space Engineering; Sato, M.; Ninomiya, T.; Hasegawa, T. [Central Research Inst. of Electric Power Industry, Yokosuka, Kanagawa (Japan)

1996-07-01

419

Greenhouse Impact Due to the Use of Combustible Fuels: Life Cycle Viewpoint and Relative Radiative Forcing Commitment  

PubMed Central

Extensive information on the greenhouse impacts of various human actions is important in developing effective climate change mitigation strategies. The greenhouse impacts of combustible fuels consist not only of combustion emissions but also of emissions from the fuel production chain and possible effects on the ecosystem carbon storages. It is important to be able to assess the combined, total effect of these different emissions and to express the results in a comprehensive way. In this study, a new concept called relative radiative forcing commitment (RRFC) is presented and applied to depict the greenhouse impact of some combustible fuels currently used in Finland. RRFC is a ratio that accounts for the energy absorbed in the Earth system due to changes in greenhouse gas concentrations (production and combustion of fuel) compared to the energy released in the combustion of fuel. RRFC can also be expressed as a function of time in order to give a dynamic cumulative picture on the caused effect. Varying time horizons can be studied separately, as is the case when studying the effects of different climate policies on varying time scales. The RRFC for coal for 100 years is about 170, which means that in 100 years 170 times more energy is absorbed in the atmosphere due to the emissions of coal combustion activity than is released in combustion itself. RRFC values of the other studied fuel production chains varied from about 30 (forest residues fuel) to 190 (peat fuel) for the 100-year study period. The length of the studied time horizon had an impact on the RRFC values and, to some extent, on the relative positions of various fuels. PMID:18521657

Palosuo, Taru; Holmgren, Kristina; Savolainen, Ilkka

2008-01-01

420

Preparation and properties of densified refuse-derived fuel  

SciTech Connect

Refuse-derived fuel (RDF) generally refers to the product of the mechanical (or chemical plus mechanical) processing of municipal solid waste (MSW) to produce a specification output. Densified refuse-derived fuel (d-RDF) is the product of the mechanical compaction of some form of RDF to agglomerated pieces which are sufficiently cohesive to sustain storage and handling. The term densified is used in the generic sense to include all forms of compaction, such as extrusion or rolling to produce briquettes, pellets, cubettes, etc. Generally, d-RDF is a fuel for stoker boilers analogous to lump coal. The concept of RDF and d-RDF can be extended to other waste-derived or biomass fuels. The pilot-scale preparation of d-RDF has been described. This paper is to update and expand the information and to describe the objectives and operation of some of the unit processes used and the properties of the d-RDF. It should be an objective of processing to maximize the quality of the fuel, even at the expense of quantity, so as to maintain the fuel specification. Thus, a mass of waste, m, is converted to a mass of fuel, m', so that m > m', but the heats of combustion are ..delta..H/sub m/ < ..delta..H/sub m'/, which is the objective of processing. The yield is limited by the composition of m and the limits of the law of conservation of mass-energy; also, allowance must be made for the energy input for processing. The concept of processing to maximize yield is opposite to the traditional objective of waste management of maximizing disposal.

Alter, H.; Campbell, J.A.

1980-01-01

421

The effect of initial flow nonuniformity on second-stage fuel injection and combustion in a supersonic duct. [supersonic combustion ramjet engine  

NASA Technical Reports Server (NTRS)

The effects of flow nonuniformity on second-stage hydrogen fuel injection and combustion in supersonic flow were evaluated. The first case, second-stage fuel injection into a uniform duct flow, produced data indicating that fuel mixing is considerably slower than estimates based on an empirical mixing correlation. The second-case, two-stage fuel injection (or second-stage fuel injection into a nonuniform duct flow), produced a large interaction between stages with extensive flow separation. For this case the measured wall pressure, heat transfer, and amount of reaction at the duct exit were significantly greater than estimates based on the mixing correlation. Substantially more second-stage fuel burned in the second case than in the first case. Overall effects of unmixedness/chemical kinetics were found not to be significant at the exit for stoichiometric fuel injection.

Russin, W. R.

1975-01-01

422

Nitrogen Oxides, Sulfur Trioxide, and Mercury Emissions during Oxy-fuel Fluidized Bed Combustion of Victorian Brown Coal.  

PubMed

This study investigates, for the first time, the NOx, N2O, SO3, and Hg emissions from combustion of a Victorian brown coal in a 10 kWth fluidized bed unit under oxy-fuel combustion conditions. Compared to air combustion, lower NOx emissions and higher N2O formation were observed in the oxy-fuel atmosphere. These NOx reduction and N2O formations were further enhanced with steam in the combustion environment. The NOx concentration level in the flue gas was within the permissible limit in coal-fired power plants in Victoria. Therefore, an additional NOx removal system will not be required using this coal. In contrast, both SO3 and gaseous mercury concentrations were considerably higher under oxy-fuel combustion compared to that in the air combustion. Around 83% of total gaseous mercury released was Hg(0), with the rest emitted as Hg(2+). Therefore, to control harmful Hg(0), a mercury removal system may need to be considered to avoid corrosion in the boiler and CO2 separation units during the oxy-fuel fluidized-bed combustion using this coal. PMID:25402169

Roy, Bithi; Chen, Luguang; Bhattacharya, Sankar

2014-12-16

423

Health effects of residential wood smoke particles: the importance of combustion conditions and physicochemical particle properties  

PubMed Central

Background Residential wood combustion is now recognized as a major particle source in many developed countries, and the number of studies investigating the negative health effects associated with wood smoke exposure is currently increasing. The combustion appliances in use today provide highly variable combustion conditions resulting in large variations in the physicochemical characteristics of the emitted particles. These differences in physicochemical properties are likely to influence the biological effects induced by the wood smoke particles. Outline The focus of this review is to discuss the present knowledge on physicochemical properties of wood smoke particles from different combustion conditions in relation to wood smoke-induced health effects. In addition, the human wood smoke exposure in developed countries is explored in order to identify the particle characteristics that are relevant for experimental studies of wood smoke-induced health effects. Finally, recent experimental studies regarding wood smoke exposure are discussed with respect to the applied combustion conditions and particle properties. Conclusion Overall, the reviewed literature regarding the physicochemical properties of wood smoke particles provides a relatively clear picture of how these properties vary with the combustion conditions, whereas particle emissions from specific classes of combustion appliances are less well characterised. The major gaps in knowledge concern; (i) characterisation of the atmospheric transformations of wood smoke particles, (ii) characterisation of the physicochemical properties of wood smoke particles in ambient and indoor environments, and (iii) identification of the physicochemical properties that influence the biological effects of wood smoke particles. PMID:19891791

Kocbach B°lling, Anette; Pagels, Joakim; Yttri, Karl Espen; Barregard, Lars; Sallsten, Gerd; Schwarze, Per E; Boman, Christoffer

2009-01-01

424

Identification and quantification analysis of nonlinear dynamics properties of combustion instability in a diesel engine  

NASA Astrophysics Data System (ADS)

The cycling combustion instabilities in a diesel engine have been analyzed based on chaos theory. The objective was to investigate the dynamical characteristics of combustion in diesel engine. In this study, experiments were performed under the entire operating range of a diesel engine (the engine speed was changed from 600 to 1400 rpm and the engine load rate was from 0% to 100%), and acquired real-time series of in-cylinder combustion pressure using a piezoelectric transducer installed on the cylinder head. Several methods were applied to identify and quantitatively analyze the combustion process complexity in the diesel engine including delay-coordinate embedding, recurrence plot (RP), Recurrence Quantification Analysis, correlation dimension (CD), and the largest Lyapunov exponent (LLE) estimation. The results show that the combustion process exhibits some determinism. If LLE is positive, then the combustion system has a fractal dimension and CD is no more than 1.6 and within the diesel engine operating range. We have concluded that the combustion system of diesel engine is a low-dimensional chaotic system and the maximum values of CD and LLE occur at the lowest engine speed and load. This means that combustion system is more complex and sensitive to initial conditions and that poor combustion quality leads to the decrease of fuel economy and the increase of exhaust emissions.

Yang, Li-Ping; Ding, Shun-Liang; Litak, Grzegorz; Song, En-Zhe; Ma, Xiu-Zhen

2015-01-01

425

Identification and quantification analysis of nonlinear dynamics properties of combustion instability in a diesel engine.  

PubMed

The cycling combustion instabilities in a diesel engine have been analyzed based on chaos theory. The objective was to investigate the dynamical characteristics of combustion in diesel engine. In this study, experiments were performed under the entire operating range of a diesel engine (the engine speed was changed from 600 to 1400?rpm and the engine load rate was from 0% to 100%), and acquired real-time series of in-cylinder combustion pressure using a piezoelectric transducer installed on the cylinder head. Several methods were applied to identify and quantitatively analyze the combustion process complexity in the diesel engine including delay-coordinate embedding, recurrence plot (RP), Recurrence Quantification Analysis, correlation dimension (CD), and the largest Lyapunov exponent (LLE) estimation. The results show that the combustion process exhibits some determinism. If LLE is positive, then the combustion system has a fractal dimension and CD is no more than 1.6 and within the diesel engine operating range. We have concluded that the combustion system of diesel engine is a low-dimensional chaotic system and the maximum values of CD and LLE occur at the lowest engine speed and load. This means that combustion system is more complex and sensitive to initial conditions and that poor combustion quality leads to the decrease of fuel economy and the increase of exhaust emissions. PMID:25637916

Yang, Li-Ping; Ding, Shun-Liang; Litak, Grzegorz; Song, En-Zhe; Ma, Xiu-Zhen

2015-01-01

426

Highly Time-Resolved Imaging of Combustion and Pyrolysis Product Concentrations in Solid Fuel Combustion: NO Formation in a Burning Cigarette.  

PubMed

The highly dynamic, heterogeneous combustion process within a burning cigarette was investigated by a miniaturized extractive sampling probe (microprobe) coupled to photoionization mass spectrometry using soft laser single photon ionization (SPI) for online real-time detection of molecular ions of combustion and pyrolysis products. Research cigarettes smoked by a smoking machine are used as a reproducible model system for solid-state biomass combustion, which up to now is not addressable by current combustion-diagnostic tools. By combining repetitively recorded online measurement sequences from different sampling locations in an imaging approach, highly time- and space-resolved quantitative distribution maps of, e.g., nitrogen monoxide, benzene, and oxygen concentrations were obtained at a near microscopic level. The obtained quantitative distribution maps represent a time-resolved, movie-like imaging of the respective compound's formation and destruction zones in the various combustion and pyrolysis regions of a cigarette during puffing. Furthermore, spatially resolved kinetic data were ascertainable. The here demonstrated methodology can also be applied to various heterogenic combustion/pyrolysis or reaction model systems, such as fossil- or biomass-fuel pellet combustion or to a positional resolved analysis of heterogenic catalytic reactions. PMID:25582882

Zimmermann, Ralf; Hertz-SchŘnemann, Romy; Ehlert, Sven; Liu, Chuan; McAdam, Kevin; Baker, Richard; Streibel, Thorsten

2015-02-01

427

Meat and bone meal as secondary fuel in fluidized bed combustion  

SciTech Connect

Meat and Bone Meal (MBM) was co-fired in a laboratory scale fluidized bed combustion (FBC) apparatus with two coals. Several fuel blends were combusted under different conditions to study how primary fuel substitution by MBM affects flue gas emissions as well as fluidized bed (FB) agglomeration tendency. MBM, being a highly volatile fuel, caused significant increase of CO emissions and secondary air should be used in industrial scale applications to conform to regulations. The high N-content of MBM is moderately reflected on the increase of nitrogen oxides emissions which are reduced by MBM derived volatiles. The MBM ash, mainly containing bone material rich in Ca, did not create any noteworthy desulphurization effect. The observed slight decrease in SO{sub 2} emissions is predominantly attributed to the lower sulphur content in the coal/MBM fuel mixtures. The SEM/EDS analysis of bed material samples from the coal/MBM tests revealed the formation of agglomerates of bed material debris and ash with sizes that do not greatly exceed the original bed inventory and thus not problematic. 37 refs., 9 figs., 3 tabs.

L. Fryda; K. Panopoulos; P. Vourliotis; E. Kakaras; E. Pavlidou [National Technical University of Athens, Athens (Greece). Laboratory of Steam Boilers and Thermal Plants, School of Mechanical Engineering

2007-07-01

428

Fuel-Flexible Combustion System for Co-production Plant Applications  

SciTech Connect

Future high-efficiency, low-emission generation plants that produce electric power, transportation fuels, and/or chemicals from fossil fuel feed stocks require a new class of fuel-flexible combustors. In this program, a validated combustor approach was developed which enables single-digit NO{sub x} operation for a future generation plants with low-Btu off gas and allows the flexibility of process-independent backup with natural gas. This combustion technology overcomes the limitations of current syngas gas turbine combustion systems, which are designed on a site-by-site basis, and enable improved future co-generation plant designs. In this capacity, the fuel-flexible combustor enhances the efficiency and productivity of future co-production plants. In task 2, a summary of market requested fuel gas compositions was created and the syngas fuel space was characterized. Additionally, a technology matrix and chemical kinetic models were used to evaluate various combustion technologies and to select two combustor concepts. In task 4 systems analysis of a co-production plant in conjunction with chemical kinetic analysis was performed to determine the desired combustor operating conditions for the burner concepts. Task 5 discusses the experimental evaluation of three syngas capable combustor designs. The hybrid combustor, Prototype-1 utilized a diffusion flame approach for syngas fuels with a lean premixed swirl concept for natural gas fuels for both syngas and natural gas fuels at FA+e gas turbine conditions. The hybrid nozzle was sized to accommodate syngas fuels ranging from {approx}100 to 280 btu/scf and with a diffusion tip geometry optimized for Early Entry Co-generation Plant (EECP) fuel compositions. The swozzle concept utilized existing GE DLN design methodologies to eliminate flow separation and enhance fuel-air mixing. With changing business priorities, a fully premixed natural gas & syngas nozzle, Protoytpe-1N, was also developed later in the program. It did not have the diluent requirements of Prototype-1 and was demonstrated at targeted gas turbine conditions. The TVC combustor, Prototype-2, premixes the syngas with air for low emission performance. The combustor was designed for operation with syngas and no additional diluents. The combustor was successfully operated at targeted gas turbine conditions. Another goal of the program was to advance the status of development tools for syngas systems. In Task 3 a syngas flame evaluation facility was developed. Fundamental data on syngas flame speeds and flame strain were obtained at pressure for a wide range of syngas fuels with preheated air. Several promising reduced order kinetic mechanisms were compared with the results from the evaluation facility. The mechanism with the best agreement was selected for application to syngas combustor modeling studies in Task 6. Prototype-1 was modeled using an advanced LES combustion code. The tools and combustor technology development culminate in a full-scale demonstration of the most promising technology in Task 8. The combustor was operated at engine conditions and evaluated against the various engine performance requirements.

Joel Haynes; Justin Brumberg; Venkatraman Iyer; Jonathan Janssen; Ben Lacy; Matt Mosbacher; Craig Russell; Ertan Yilmaz; Williams York; Willy Ziminsky; Tim Lieuwen; Suresh Menon; Jerry Seitzman; Ashok Anand; Patrick May

2008-12-31

429

Potential hazards associated with combustion of bio-derived versus petroleum-derived diesel fuel  

PubMed Central

Fuels from renewable resources have gained worldwide interest due to limited fossil oil sources and the possible reduction of atmospheric greenhouse gas. One of these fuels is so called biodiesel produced from vegetable oil by transesterification into fatty acid methyl esters (FAME). To get a first insight into changes of health hazards from diesel engine emissions (DEE) by use of biodiesel scientific studies were reviewed which compared the combustion of FAME with common diesel fuel (DF) for legally regulated and non-regulated emissions as well as for toxic effects. A total number of 62 publications on chemical analyses of DEE and 18 toxicological in vitro studies were identified meeting the criteria. In addition, a very small number of human studies and animal experiments were available. In most studies, combustion of biodiesel reduces legally regulated emissions of carbon monoxide, hydrocarbons, and particulate matter. Nitrogen oxides are regularly increased. Among the non-regulated emissions aldehydes are increased, while polycyclic aromatic hydrocarbons are lowered. Most biological in vitro assays show a stronger cytotoxicity of biodiesel exhaust and the animal experiments reveal stronger irritant effects. Both findings are possibly caused by the higher content of nitrogen oxides and aldehydes in biodiesel exhaust. The lower content of PAH is reflected by a weaker mutagenicity compared to DF exhaust. However, recent studies show a very low mutagenicity of DF exhaust as well, probably caused by elimination of sulfur in present DF qualities and the use of new technology diesel engines. Combustion of vegetable oil (VO) in common diesel engines causes a strongly enhanced mutagenicity of the exhaust despite nearly unchanged regulated emissions. The newly developed fuel ôhydrotreated vegetable oilö (HVO) seems to be promising. HVO has physical and chemical advantages compared to FAME. Preliminary results show lower regulated and non-regulated emissions and a decreased mutagenicity. PMID:22871157

BŘnger, JŘrgen; Krahl, JŘrgen; Schr÷der, Olaf; Schmidt, Lasse; Westphal, G÷tz A.

2012-01-01

430

Life cycle comparison of fuel cell vehicles and internal combustion engine vehicles for Canada and the United States  

Microsoft Academic Search

The objective of this study is to put forward a full analysis of the impact of the difference between the Canadian and American energy realities on the life cycle of fuel cell vehicles and internal combustion engine vehicles. Electricity is a major type of energy used in the transportation sector. Electricity is needed in the production of feedstock of fuel,

Nada Zamel; Xianguo Li

2006-01-01

431

Combustion of nanofluid fuels with the addition of boron and iron particles at dilute and dense concentrations  

E-print Network

stage when all the liquid fuel had been consumed. Sometimes this agglomerate may not burn if the energy energy density, easier and faster ignition, enhanced catalytic effects, and improved combustion a simple hot plate experiment, reported that the ignition probability of diesel fuel containing a small

Qiao, Li

432

Prediction of Co-Firing Characteristics of Wastes in Circulating Fluidized Bed by Fuel Properties  

NASA Astrophysics Data System (ADS)

The purpose of this study is to experimentally investigate the co-firing characteristics of different kinds of wastes in circulating fluidized bed combustors, and further to correlate the acquired combustion efficiency with fuel property parameters. The tested individual fuels were wasted tire, RPF, wood tip, RDF and coal, which typified the fuels with distinctively different contents of volatile matters. Coal was employed to represent the fuel containing particularly low volatile matters. The experiments were carried out in a pilot circulating fluidized bed combustor, and varied parameters included the fuel blending ratio, furnace temperature and secondary air ratio. The acquired results indicated that co-firing wasted tire and RPF led to higher CO concentration in the flue gas than firing RPF independently, and this CO concentration increased with increasing the blending ratio of wasted tire. The lower volatile matter content, higher carbon to hydrogen ratio (C?H ratio) and carbon to oxygen ratio (C?O ratio) of wasted tire than those of RPF were suggested to be responsible for the results. The study also found that the available combustion efficiencies in co-firing various pairs of the tested fuels were correlative with the volatile matter contents, C?H and C?O ratios of the blended fuels estimated as the weighed sums of the same property parameters of individual fuels. This allows thus a simple determination of the co-firing efficiency of any fuel blend from calculating the blend?s fuel property parameters using the fuel blending ratio as a weight.

Murakami, Takahiro; Suda, Toshiyuki

433

Nitride Fuel Modeling Recommendation for Nitride Fuel Material Property Measurement Priority  

Microsoft Academic Search

The purpose of this effort was to provide the basis for a model that effectively predicts nitride fuel behavior. Material property models developed for the uranium nitride fuel system have been used to approximate the general behavior of nitride fuels with specific property models for the transuranic nitride fuels utilized as they become available. The AFCI fuel development program now

William Carmack; Richard Moore

2005-01-01

434

Fuel correlations for combustion purposes, a summary of progress within the past fifteen years. Part 1  

SciTech Connect

Over the years, many correlations for fuel properties have been developed at Laval University. The main goal in this was to provide tools to estimate unknown fuel properties form the known values of the density and the viscosity at one temperature and the ASTM D-86 distillation, since these data are easily determined. For liquid fuels the target was set to establish as many fuel properties as possible which could be derived from three measurements (1) the density at 298 K, (2) the ASTM distillation, (3) the fuel viscosity at a single temperature. These correlations have been published piecemeal in the literature or in report form, but not as an ensemble. The objective of the present work is to list the available correlations and indicate their accuracy and applications.

Kretschmer, D.; Odgers, J. [Laval Univ., Quebec City, Quebec (Canada). Dept. of Mechanical Engineering

1996-12-31

435

Predicting gaseous emissions from small-scale combustion of agricultural biomass fuels.  

PubMed

A prediction model of gaseous emissions (CO, CO2, NOx, SO2 and HCl) from small-scale combustion of agricultural biomass fuels was developed in order to rapidly assess their potential to be burned in accordance to current environmental threshold values. The model was established based on calculation of thermodynamic equilibrium of reactive multicomponent systems using Gibbs free energy minimization. Since this method has been widely used to estimate the composition of the syngas from wood gasification, the model was first validated by comparing its prediction results with those of similar models from the literature. The model was then used to evaluate the main gas emissions from the combustion of four dedicated energy crops (short-rotation willow, reed canary grass, switchgrass and miscanthus) previously burned in a 29-kW boiler. The prediction values revealed good agreement with the experimental results. The model was particularly effective in estimating the influence of harvest season on SO2 emissions. PMID:25543541

Fournel, S; Marcos, B; Godbout, S; Heitz, M

2015-03-01

436

Investigation of Sooting in Microgravity Droplet Combustion: Fuel-Dependent Effects  

NASA Technical Reports Server (NTRS)

Kumagai and coworkers first performed microgravity droplet combustion experiments [Kumagai, 1957]. The primary goal of these early experiments were to validate simple 'd(sup 2)-law models [Spalding, 1954, Godsave, 1954] Inherent in the 'd(sup 2) -law' formulation and in the scope of the experimental observation is the neglect of sooting behavior. In fact, the influence of sooting has not received much attention until more recent works [Choi et al., 1990; Jackson et al., 1991; Jackson and Avedisian, 1994; Choi and Lee, 1996; Jackson and Avedisian, 1996; Lee et al., 1998]:. Choi and Lee measured soot volume fraction for microgravity droplet flames using full-field light extinction and subsequent tomographic inversion [Choi and Lee, 1996]. In this investigation, soot concentrations were measured for heptane droplets and it was reported that soot concentrations were considerably higher in microgravity compared to the normal gravity flame. It was reasoned that the absence of buoyancy and the effects of thermophoresis resulted in the higher soot concentrations. Lee et al. [1998] performed soot measurement experiments by varying the initial droplet diameter and found marked influence of sooting on the droplet burning behavior. There is growing sentiment that sooting in droplet combustion must no longer be neglected and that "perhaps one of the most important outstanding contributions of (micro)g droplet combustion is the observation that in the absence of asymmetrical forced and natural convection, a soot shell is formed between the droplet surface and the flame, exerting an influence on the droplet combustion response far greater than previously recognized." [Law and Faeth, 1994]. One of the methods that we are exploring to control the degree of sooting in microgravity is to use different fuels. The effect of fuel structure on sooting propensity has been investigated for over-ventilated concentric coflowing buoyant diffusion flames. (Glassman, 1996]. In these investigations, the fuel flowrate was increased until smoke was observed to escape from the "luminous visible flame" [Glassman, 1996]. A total of 29 fuels were used in order to characterize relative sooting propensity. The sooting propensity of a particular fuel was assessed by comparing the flowrates for soot emission from the tip of the flame. It was reported that the sooting tendency for diffusion flames increased for fuels with higher rates of pyrolysis. Randolph and Law [1986 and not 1994] also examined the effect of fuel structure on droplet sooting behavior. In their experiments the droplets were separated from the bulk gas stream and quenched with nitrogen prior to gravimetric measurements. A variety of fuels were studied, namely aromatics, phenyl-alkanes and alkanes. The results were in qualitative agreement with the work of Glassman [1986]. Vander Wal et al. [1994] performed relative soot concentration measurements using laser-induced incandescence for heptane and decane fuel droplets burning under normal-gravity conditions. It was found that soot volume fractions for decane was more than a factor of two larger than that for heptane. Although the normal-gravity investigations have provided some important insights regarding the influence of fuel structure on the sooting behavior of droplet flames, results cannot be easily extrapolated for microgravity studies since increased residence times and thermophoretic effects must be considered in greater detail. Several studies have compared sooting behavior of different fuel droplets burning under microgravity conditions [Card and Choi, 1990; Jackson et al., 1991; Jackson and Avedisian, 1994], however, detailed quantitative results were not provided. In all of these previous studies, the degree of sooting was only visually assessed from an incandescent backlighted image of the soot containing region. Such techniques can provide misleading results regarding sooting behavior [Choi, 1996].

Manzello, Samuel L.; Hua, Ming; Choi, Mun Young

1999-01-01

437

The NACA Apparatus for Studying the Formation and Combustion of Fuel Sprays and the Results from Preliminary Tests  

NASA Technical Reports Server (NTRS)

This report describes the apparatus as designed and constructed at the Langley Memorial Aeronautical Laboratory, for studying the formation and combustion of fuel sprays under conditions closely simulating those occurring in a high-speed compression-ignition engine. The apparatus consists of a single-cylinder modified test engine, a fuel-injection system so designed that a single charge of fuel can be injected into the combustion chamber of the engine, an electric driving motor, and a high-speed photographic apparatus. The cylinder head of the engine has a vertical-disk form of combustion chamber whose sides are glass windows. When the fuel is injected into the combustion chamber, motion pictures at the rate of 2,000 per second are taken of the spray formation by means of spark discharges. When combustion takes place the light of the combustion is recorded on the same photographic film as the spray photographs. The report includes the results of some tests to determine the effect of air temperature, air flow, and nozzle design on the spray formation.

Rothrock, A M

1933-01-01

438

Measurement of temperature, fuel concentration and equivalence ratio fields using tracer LIF in IC engine combustion  

NASA Astrophysics Data System (ADS)

A technique based on planar laser-induced fluorescence of 3-pentanone, for measurements of absolute concentration, temperature and fuel/air equivalence ratios in turbulent, high-pressure combustion systems such as an internal combustion engine is presented. Quasi-simultaneous excitation with 248 nm and 308 nm of 3-pentanone that is used as a fluorescence tracer doped to iso-octane, yields pairs of strongly temperature-dependent fluorescence images. Previous investigations have resulted in information on temperature and pressure dependence of absorption cross-sections and fluorescence quantum yields. Using these data the ratio of corresponding fluorescence images can be converted to temperature images. Instantaneous temperature distribution fields in the compression stroke and in the unburned end-gas of an SI engine were measured. The temperature fields obtained from the two-line technique are used to correct the original tracer-LIF images in order to evaluate quantitative fuel distributions in terms of number densities and fuel/air equivalence ratio.

Einecke, S.; Schulz, C.; Sick, V.

2000-11-01

439

Comparison of fuel injection systems and a new combustion method for a direct injection two-stroke-cycle automobile engine  

Microsoft Academic Search

A study of a direct fuel injection 2-stroke engine as a new generation power unit was performed and concluded as follows. 1.(1) A comparison of fuel injection system candidates was made and the one-fluid high-pressure type was chosen.2.(2) Adopting the high-pressure fuel system to a single-cylinder engine, stratified charge combustion was realized using the late injection.3.(3) It was found that

Koji Morikawa; Hideo Watanabe; Akira Furuya

1996-01-01

440

Transient air-fuel ratio H? preview control of a drive-by-wire internal combustion engine  

Microsoft Academic Search

An approach for H? Preview control of the transient air-fuel ratio control of a drive-by-wire internal combustion engine system is proposed. The fuel delivery system has significant transport and measurement delays. A preview fuel control algorithm, which uses the current measurement or estimate of air charge as well as the corresponding predicted future air charge, provides compensation for these delays.

Larry Mianzot; Huei Pengt; I. Haskara