Transactions of the Korean Society of Automotive Engineers (한국자동차공학회논문집)

The Korean Society of Automotive Engineers (한국자동차공학회)
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Engine Cycle Simulation for the Effects of EGR on Combustion and Emissions in a DI Diesel Engine

직분식 디젤엔진에서 EGR이 연소특성 및 배출가스에 미치는 영향에 대한 시뮬레이션 연구

  • Published : 2002.07.01
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Abstract

In this study, cycle simulation was performed to investigate the effect of EGR on combustion characteristics and emissions including NO and soot using a two-zone model in a DI diesel engine. The NO formation was well predicted for different EGR rate and temperature using a two-zone model. The oxygen in the inlet charge was replaced by CO$_2$ and H$_2$O with EGR. The reduction in the inlet charge oxygen resulted in very large reduction in NO level at the same inlet charge temperature. The effect of EGR was to reduce the burned gas temperature. When EGR was increased from 0% to 15%, the peak flame temperature was decreased by 50$\^{C}$ and it caused about 57% NO reduction. EGR caused increase of the overall inlet charge temperature which offset some of benefit of lower flame temperature resulting from O$_2$ displacement. Cooling the EGR was confirmed to provide additional benefits by lowering NO emission. It also reduced soot emission.

Keywords

References

  1. J. B. Heywood, Internal Combustion Engine fundamentals, McGraw-Hill, Inc. New York, 1988
  2. N. Ladommatos, 'The Effect of Exhaust Gas Recirculation on Combustion and NOx Emissions in a High-Speed Direct-Injection Diesel Engine,' SAE 960840, 1996
  3. N. Ladommatos, 'The Dilution, Chemical, and Thermal Effects of Exhaust Gas Recirculation on Diesel Engine Emissions-Part 1 : Effect of Reducing Inlet Charge Oxygen,' SAE 961165, 1996
  4. S. Ropke, 'NOx Formation in Diesel Engines for Various Fuels and Intake Gases,' SAE 950213, 1995
  5. T. Chikahisa, 'Analysis of NO Formation Characteristics and Control Concepts in Diesel Engines from NO Reaction-Kinetic Considerations,' SAE 950215, 1995
  6. D. N. Assanis, 'A Computer Simulation of the Turbocharged Turbocompounded Diesel System for Studies of Low-Heat-Rejection Engine Performance,' Ph. D Thesis, 1985
  7. 이교승, '직접분사식 NA 디젤엔진의 사이클 시물레이션-I,' 한국자동차공학회 논문집, 제7권 제3호, pp.12-28, 1999
  8. 김철환, '2영역 모델을 이용한 EGR사용 직접분사식 디젤엔진의 NOx 생성예측,' 대한기계학회논문집, 제24권 제3호, pp.390-401, 2000
  9. M. Ishida, 'Combustion Analysis by Two-Zone Model in a DI Diesel Engine,' COMODIA 94, pp.309-314, 1994
  10. N. Watson, M. S. Janata, Turbo-charging the International Combustion Engine, John Wiley & Sons, New York. 1982
  11. S. H. Mansouri, "Divided-Chamber Diesel Engines, Part 1: A Cycle Simulation which Predicts Performance and Emissions,' SAE 820273, 1982
  12. S. G. Poulos, J. B. Heywood, 'The Effect of Chamber Geometry on SI Engine Combustion Rate - A Modeling Study,' M.I.T. Dept. of Mech. Engr., S.M. Thesis, 1982
  13. B. W. Millington, E. R. Hartles, 'Friction Loss in Diesel Engines,' SAE 680590, 1968
  14. H. Hiroyasu, 'Model for Combustion and Formation of Nitric Oxide and Soot in DI Diesel Engines,' SAE 760129, 1976
  15. G. D. Lee, 'A PC-Based Model for Predicting NOx Reductions in Diesel Engines,' SAE 962060, 1996
  16. 노승민, 직접분사식 디젤엔진에서 배기재순환율과 온도가 NOx와 PM저감에 미치는 영향에 관한 실험적 연구, 연세대학교 기계공학과 석사학위 논문, 2001