This content is not included in
your SAE MOBILUS subscription, or you are not logged in.
Unburned Hydrocarbon Emissions from Stratified Charge Direct Injection Engines
Technical Paper
2003-01-3099
ISSN: 0148-7191, e-ISSN: 2688-3627
Annotation ability available
Sector:
Language:
English
Abstract
The sources of unburned hydrocarbon (UHC) emissions in direct injection stratified charge engines are presented. Whereas crevices in the combustion chamber are the primary sources of UHC emissions in homogeneous charge engines, lean quenching and liquid film layers dominate UHC emissions in stratified charge operation. Emissions data from a single cylinder engine, operating in stratified charge mode at a low speed / light load condition is summarized. This operating point is interesting in that liquid film formation, as evidenced by smoke emissions, is minimal, thus highlighting the lean quenching process. The effects of operating parameters on UHC emissions are demonstrated via sweeps of spark advance, injection timing, manifold pressure, and swirl level. The effects of EGR dilution are also discussed. Spark advance is shown to be the most significant factor in UHC emissions.
A semi-empirical model for UHC emissions is presented based on the analysis of existing engine data. The UHC model uses computational fluid dynamics (CFD) to predict the mass of fuel distributed in extremely lean regions and the piston wetting - believed to be the primary sources of UHC emissions in stratified charge operation. When corrected for spark advance, the model predictions correlate well with measured UHC emissions, demonstrating the potential to estimate the UHC emissions propensity for proposed design changes.
Recommended Content
Authors
Citation
Hilditch, J., Han, Z., and Chea, T., "Unburned Hydrocarbon Emissions from Stratified Charge Direct Injection Engines," SAE Technical Paper 2003-01-3099, 2003, https://doi.org/10.4271/2003-01-3099.Also In
Gasoline Direct Injection Engine and Spark Ignition Performance
Number: SP-1807; Published: 2003-10-31
Number: SP-1807; Published: 2003-10-31
References
- Heywood, J.B. Internal Combustion Engine Fundamentals Mc-Graw-Hill New York 1988
- Drake M.C. Fansler T.D. Solomon A.S. Szekely, G.A. Jr. “Piston Fuel Films as a Source of Smoke and Hydrocarbon Emissions from a Wall-Controlled Sprak-Ignited Direct-Injection Engine,” SAE Paper 2003-01-0547
- Stanglmaier R. Li J. Matthews R. “The Effect of In-Cylinder Wall Wetting Location on the HC Emissions from SI Engines,” SAE Paper 1999-01-0502 1999
- Li J. Matthews R. Stanglemaier R. Roberts C. Anderson R. “Further Experiments on the Effects of In-Cylinder Wall Wetting on HC Emissions from Direct Injection Gasoline Engines,” SAE Paper 1999-01-3661 1999
- Sandquist H. Lindgren R. Denbratt I. “Sources of Hydrocarbon Emissions from a Direct Injection Stratified Charge Spark Ignition Engine,” SAE Paper 2000-01-1906 2000
- Wierzba I. Bade Shrestha S.O. Karim G.A. “An Approach for Predicting the Flammability Limits of Fuel/Diluent Mixtures in Air,” J. Inst. of Energy 69 122 130 1996
- Han Z. Yi J. Trigui N. “Stratified Mixture Formation and Piston Surface Wetting in a DISI Engine,” SAE Paper 2002-01-2655 2002
- Wu K.-C. Hochgreb S. “Numerical Simulation of Post-Flame Oxidation of Hydrocarbons in Spark Ignition Engines,” SAE Paper 970886 1997
- Amsden, A. A. KIVA-3V: “A Block-Structured KIVA Program for Engines with Vertical or Canted Valves,” Los Alamos National Laboratory Report LA-13313-MS 1997
- Amsden, A. A. “KIVA-3V, Release 2: Improvements to KIVA-3V” Los Alamos National Laboratory Report LA-13608-MS 1999
- Han, Z. Xu, Z. Trigui, N. “Spray/Wall Interaction Models for Multidimensional Engine Simulation,” International Journal of Engine Research 1 127 146 2000
- Han, Z. Xu, Z. Wooldridge, S. T. Yi, J. Lavoie, G. “Modeling of DISI Engine Sprays with Comparison to Experimental In-Cylinder Spray Images,” SAE Paper 2001-01-3667 2001
- Han, Z. Xu, Z. “Wall Film Dynamics Modeling for Impinging Sprays in Engines,” SAE 2004 World Congress 2004