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Effect of Injection Pressure and Injection Timing on Spray and Flame Characteristics of Spray-Guided Direct-Injection Spark-Ignition Engine under Lean Stratified Combustion Operation

성층희박연소 운전조건에서 분사시기에 따른 분무유도식 직접분사 가솔린엔진의 분무 및 화염특성

  • Oh, Heechang (Department of Mechanical Engineering, Korea Advanced Institute of Science and Technology) ;
  • Lee, Minsuk (Department of Mechanical Engineering, Korea Advanced Institute of Science and Technology) ;
  • Park, Jungseo (Department of Mechanical Engineering, Korea Advanced Institute of Science and Technology) ;
  • Bae, hoongsik (Department of Mechanical Engineering, Korea Advanced Institute of Science and Technology)
  • 오희창 (한국과학기술원 기계공학과) ;
  • 이민석 (한국과학기술원 기계공학과) ;
  • 박정서 (한국과학기술원 기계공학과) ;
  • 배충식 (한국과학기술원 기계공학과)
  • Received : 2012.01.03
  • Accepted : 2012.12.26
  • Published : 2013.03.01

Abstract

An experimental study was carried out to investigate the effects of the injection timing on the spray and combustion characteristics in a spray-guided direct-injection spark-ignition (DISI) engine under lean stratified operation. An in-cylinder pressure analysis, exhaust emissions measurement, and visualization of the spray and combustion were employed in this study. The combustion in a stratified DISI engine was found to have both lean premixed and diffusion controlled flame combustion characteristics. The injection timing condition corresponding to the stratified mixture characteristics was verified to be a dominant factor for these flame characteristics. For the early injection timing, a non-luminous blue flame and low combustion efficiency were observed as a result of the lean homogeneous mixture formation. On the other hand, a luminous sooting flame was shown at the late injection timing because of an under-mixed mixture formation. In addition, the smoke emission and incomplete combustion products were increased at the late injection timing as a result of the increased locally rich area. On the other hand, the NOx emissions decreased and IMEP increased as the injection timing retarded. The combustion phasing produced by the injection timing was verified as the reason for this observation.

분무유도식 DISI엔진의 성층연소운전조건에서 분무 및 화염특성에 대한 실험적 연구가 수행되었다. 연소가시화를 통하여 성층연소 DISI의 연소는 희박 예혼합 연소와 확산연소의 성격을 모두 가지고 있는 것으로 확인되었다. 분사시기에 따른 혼합기 형성특성이 연소의 특성을 결정하는 중요한 인자임을 관찰하였다. 분무와 혼합기 가시화를 통해 낮은 분위기압에서의 over-mixing, 높은 분위기압에서의 under-mixing이 발생하는 것을 확인하였으며 이러한 혼합기 형성과정의 결과에 따라 화염특성, 연소효율 등의 연소특성이 결정되는 것을 살펴볼 수 있었다. 또한, NOx, IMEP도 분사시기에 따른 경향성을 보였으며, 분사시기에 따른 연소상의 변화에 의한 영향임을 확인하였다.

Keywords

References

  1. Zhao, F., Harrington, D. L. and Lai, M., 1999, "Automotive Gasoline Direct-Injection Engines," Progress in Energy and Combustion Science, Vol.25, pp. 437-562. https://doi.org/10.1016/S0360-1285(99)00004-0
  2. Kuwahara, K., Ueda, K. and Ando, H., 1998 "Mixing Contorl Strategy for Engine Performance Improvement in a Gasoline Direct Injection Engine," SAE International Journal of Engines, Vol.106, No.3, pp. 267-277.
  3. Sandquist, H., Lindgren, R. and Denbratt, I., 2000, "Sources of Hydrocarbon Emissions from a Direct Injection Stratified Charge Spark Ignition Engine," SAE paper 2000-01-1906.
  4. Stevens, E. and Steeper, R.. 2001, "Piston Wetting in an Optical DISI Engine: Fuel Films, Pool Fires, and Soot Generation," SAE International Journal of Engines, Vol. 110, No. 3, pp. 1287-1294.
  5. Brehob, D. D., Fleming, J. E., Haghgooie, M. and Stein, R. A., 1998, "Stratified-Charge Engine Fuel Economy and Emissions Characteristics," SAE Paper 982704.
  6. Van Der Wege, B. A., Han, Z., O'lyer, C., Munoz, R. H. and Yi, J., 2003, "Development and Analysis of a Spay Guided DISI Combustion System Concept," SAE paper 2003-01-3105.
  7. Baecker H., Kaufmann A. and Tichy M., 2007, "Experimental and Simulative Investigation on Stratification Potential of Spray-Guided GDI Combustion Systems," SAE Paper 2007-01-1407.
  8. Szekely, G. and Alkidas, A. C., 2005, "Combustion Characteristics of a Spray-Guided Direct-Injection Stratified-Charge Engine with a High-Squish Piston," SAE Paper 2005-01-1937.
  9. Oh, H., Bae, C. and Min, K., 2010, "Spray and Combustion Characteristics of Ethanol Bended Gasoline in a Spray Guided DISI engine under Lean Stratified Operation," SAE International Journal of Engines, Vol. 119, No. 3, pp. 213-222.
  10. Davy, M. H., Williams, P. A. and Anderson, R. W., 2000, "Effects of Fuel Composition on Mixture Formation in a Firing Direct-Injection Spark-Ignition Engine: An Experimental Study Using Mie-Scattering and Planar Laser-Induced Fluorescence Techniques," SAE Paper 2000-01-1904.
  11. Heywood, J. B. 1988, Internal Combustion Engine Fundamentals. Mcgrawhill.
  12. Petersen, B. R., Ekoto, I. W. and Miles, P. C., 2010, "Optical Investigation of UHC and CO Sources from Biodiesel Blends in a Light-Duty Diesel Engine Operating in a Partially Premixed Combustion Regime," SAE International Journal of Fuel and Lubricant, Vol. 119, No. 3, pp. 414-434.
  13. Kook, S., Bae, C., Miles, P. C., Choi, D. and Pickett, L. M., 2005, "The Influence of Charge Dilution and Injection Timing on Low-Temperature Diesel Combustion and Emissions," SAE International Journal of Fuel and Lubricant, Vol. 114, No. 4, pp. 1575-1595.
  14. Mueller, C. and Martin, G., 2002, "Effects of Oxygenated Compounds on Combustion and Soot Evolution in a DI Diesel Engine: Broadband Natural Luminosity Imaging," SAE Paper 2002-01-1631.
  15. Kume, T., Iwamoto, Y., Iida, K., Murakami, M., Akishino, K. and Ando, K., 1996, "Combustion Control Technologies for Direct Injection SI Engine," SAE International Journal of Engines, Vol. 105, No. 3, pp. 704-717.
  16. Drake M. C., Fansler T. D. and Lippert A. M., 2005, "Stratified-charge Combustion: Modeling and Imaging of a Spray-guided Direct-injection Engine," Proceeding of Combustion Institute, Vol. 30, pp.2683-2691. https://doi.org/10.1016/j.proci.2004.07.028
  17. Hemdal, S., Andersson, M., Dahlander, P., Ochoterena, R. and Denbratt I., 2011, "In-Cylinder Soot Imaging and Emissions of Stratified Combustion in a Spark-Ignited Spray-Guided Direct-Injection Gasoline Engine," International Journal of Engine Research, Vol. 12, pp. 549-563. https://doi.org/10.1177/1468087411418167
  18. Huang, H. and Zhang, Y., 2008, "Flame Colour Characterization in the Visible and Infrared Spectrum Using a Digital Camera and Image Processing," Measurement Science and Technology, Vol. 19, No. 085406.

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