This content is not included in your SAE MOBILUS subscription, or you are not logged in.
Modeling the Effects of Late Cycle Oxygen Enrichment on Diesel Engine Combustion and Emissions
ISSN: 0148-7191, e-ISSN: 2688-3627
Published March 04, 2002 by SAE International in United States
Annotation ability available
A multidimensional simulation of Auxiliary Gas Injection (AGI) for late cycle oxygen enrichment was exercised to assess the merits of AGI for reducing the emissions of soot from heavy duty diesel engines while not adversely affecting the NOx emissions of the engine. Here, AGI is the controlled enhancement of mixing within the diesel engine combustion chamber by high speed jets of air or another gas. The engine simulated was a Caterpillar 3401 engine. For a particular operating condition of this engine, the simulated soot emissions of the engine were reduced by 80% while not significantly affecting the engine-out NOx emissions compared to the engine operating without AGI. The effects of AGI duration, timing, and orientation are studied to confirm the window of opportunity for realizing lower engine-out soot while not increasing engine out NOx through controlled enhancement of in-cylinder mixing. These studies have shown that this window occurs during the late combustion cycle, from 20 to 60 crank angle degrees after top-dead-center. During this time, the combustion chamber temperatures are sufficiently high that soot oxidation increases in response in increased mixing, but the temperature is low enough that NOx reactions are quenched. The effect of the oxygen composition of the injected air is studied for the range of compositions between 21% and 30% oxygen by volume. This is the range of oxygen enrichment that is practical to produce from an air separation membrane. Simulations showed that this level of oxygen enrichment is insufficient to provide an additional benefit by either increasing the level of soot oxidation or prolonging the window of opportunity for increasing soot oxidation through enhanced mixing.
CitationMather, D., Foster, D., Poola, R., Longman, D. et al., "Modeling the Effects of Late Cycle Oxygen Enrichment on Diesel Engine Combustion and Emissions," SAE Technical Paper 2002-01-1158, 2002, https://doi.org/10.4271/2002-01-1158.
- Yamaura K., Kakegawa T., Furuhama S., Suzuki T., Kim Y., and Shibuya H.. A Study for Reduction of Diesel Exhaust Emission by Gas Injection (1st Report: Reduction of Black Smoke by Combustible Gas Injection), volume 123, pages 129-134. Japan, 1990. in Japanese.
- Cole R. L. Marciniak T. J. Longman D. E. Marr W. W., Sekar R. R., Oxygen-Enriched Diesel Engine Experiments with Low-Grade Fuel. SAE Technical Paper 932805, Society of Automotive Engineers, Warrendale, PA, 1993.
- Mather D. K., Kurtz E. M., Foster D. E., Poola R. B., Longman D. E., Chanda A., and Vachon T. J.. A Parametric Study of the Factors that Influence the Impact of Auxiliary Gas Injection in a DI Diesel Engine. ASME, 2000.
- Patterson M. A., Kong S. C., Hampson G. J., and Reitz R. D., Modeling the Effects of Fuel Injection Characteristics on Diesel Engine Soot and NOx Emissions. SAE Technical Paper 940523, Society of Automotive Engineers, Warrendale, PA, 1994.
- Xin J., Montgomery D., and Reitz R. D.. Multidimensional Modeling of Combustion for a Six-Mode Emissions Test Cycle on a DI Diesel Engine. ASME Journal of Engineering for Gas Turbines and Power, 119:683-691, 1997.
- Hampson G. J. and Reitz R. D., Two-Color Imaging of In-Cylinder Soot Concentration and Temperature in a Heavy-Duty DI Diesel Engine with Comparison to Multidimensional Modeling for Single and Split Injections. SAE Technical Paper 980524, Society of Automotive Engineers, Warrendale, PA, 1998.