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A Three-Zone Heat Release Model for Combustion Analysis in a Natural Gas SI Engine. -Effects of Crevices and Cyclic Variations on UHC Emissions
Technical Paper
2000-01-2802
ISSN: 0148-7191, e-ISSN: 2688-3627
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English
Abstract
A thermodynamic analysis based on a pressure-time history measured during the combustion in a SI engine is a commonly used tool used for analyzing the combustion process. Both one-zone and two-zone models have been applied for this purpose.
One of the major sources of the emission of unburned hydrocarbons from SI engines is the presence of crevices in the combustion chamber where a part of the unburned fuel-air mixture is trapped during the compression and the combustion.
In this paper a three-zone heat release model including the effect of crevices is presented. The model is based on a thermodynamic analysis of three connected zones consisting of burned gas, unburned gas and gas trapped in crevices.
Engine experiments have been carried out on a natural gas SI engine. The results from these experiments have been analyzed by the model. This analysis showed that approximately 7% of the unburned fuel-air mixture are trapped in the crevices at the end of the primary combustion on this engine where the crevice volumes amount to 3% of the compression volume. The model also indicate that one underestimates the combustion rate by neglecting the effect of crevices and that the presence of crevices has a cooling effect on the unburned gas.
The developed heat release model has been used to examine the cyclic variation of the engine. This investigation showed that the maximum mass fraction burned for an average combustion cycle decreases with increasing excess air causing higher UHC emissions.
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Jensen, T. and Schramm, J., "A Three-Zone Heat Release Model for Combustion Analysis in a Natural Gas SI Engine. -Effects of Crevices and Cyclic Variations on UHC Emissions," SAE Technical Paper 2000-01-2802, 2000, https://doi.org/10.4271/2000-01-2802.Data Sets - Support Documents
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References
- Gatowski, J. A. et al. “Heat Release Analysis From Pressure Data” SAE paper 841359 1984
- Chun, Kwang Min Heywood John B. “Estimating Heat-Release and Mass-of-Mixture Burned From Spark-Ignition Engine Pressure Data” Combust. Sci. and Tech. 54 133 143 1987
- Brunt, Michael F. J. et al. “The Calculation of Heat Release Energy from Engine Cylinder Pressure” SAE paper 981052 1998
- Krieger, R. B. Borman, G. L. “The Computation of Apparent Heat Release for Internal Combustion Engine” 1966
- Guezennec, Yann G. Hamama, Wajdi “Two Heat Release Analysis of Combustion Data and Calibration of Heat Transfer Correlation in an I. C. Engine” SAE paper 1999-01-0218 1999
- Jensen, T. K Schramm, J. “Unburned Hydrocarbon Emissions from SI Engines Using Gaseous Fuels” SAE paper 1999-01-0571 1999
- Ozdor, Nir et al. “Cyclic Variability in Spark Ignition Engines A literature Survey” SAE Paper 940987 1994
- Alkidas, A. C. “Combustion-chamber crevices: the major source of engine-out hydrocarbon emissions under fully warmed conditions” Progress in Energy and Combustion Science 25 253 273 1999
- Heywood, John B. “Internal Combustion Engine Fundamentals” McGraw-Hill Inc. 1988
- Min, K. Cheng, W. K. “Oxidation of the Piston Crevice Hydrocarbon During the Expansion Process in a Spark Ignition Engine” Combust. Sci. and Tech. 106 307 326 1995
- Turns, S.R. “An Introduction to Combustion” McGraw-Hill, Inc. 1996
- Young, M. B. “Cyclic Dispersion in the Homogeneous Charge Spark Ignition Engine - A Literature Survey” SAE Paper 810020 1980
- Strehlow, Roger A. “Combustion Fundamentals” McGraw Hill & Co. 1984
- Eichelberg, G. “Some New Investigations on Old Combustion Engine Problems” 1939
- Woschni, G. “A Universally Applicable Equation for the Instantaneous Heat Transfer Coefficient in the Internal Combustion Engine” SAE paper 670931 1967