Effect of Pilot Injection on Mixture Formation, Ignition Process and Flame Development in Diesel Combustion

Abstract:

The alternative combustion strategies with systematic control of mixture formation have provided new opportunities and considerable improvement in the combustion process and response to meet the stringent emissions standards. Purpose of this research is to investigate the influences of pilot injection on the fuel-air premixing especially during ignition delay period. During this period, the interaction between fuel spray and surrounding gas prior to ignition which linked to the improvement of mixture formation, ignition process and initial heat recovery thus predominantly influences the combustion process and exhaust emissions. This study investigates the effects of pilot injection using a rapid compression machine together with the schlieren photography and direct photography methods. The detail behavior of mixture formation during ignition delay period was investigated using the schlieren photography system with a high speed digital video camera. This method can capture spray evaporation, spray interference and mixture formation clearly with real images. Ignition process and flame development were investigated by direct photography method using a light sensitive high-speed color digital video camera. Pilot injection promotes mixture formation during ignition delay period and slower oxidation reaction and thus leads to earlier rise and lower peak heat release rate.

• Periodical: Applied Mechanics and Materials (Volume 390)
• Pages: 327-332
• DOI: https://doi.org/10.4028/www.scientific.net/AMM.390.327
• Online since: August 2013
• Authors: Amir Khalid, M. Jaat, Izzuddin Zaman, B. Manshoor, Mas Fawzi
• Keywords: Diesel Combustion, Ignition Process, Mixture Formation, Rapid Compression Machine, Spray

References

[1] Horibe, N., Annen, T., Miyazaki, Y. and Ishiyama, T., Heat Release Rate and NOx Formation Process in Two-Stage Injection Diesel PCCI Combustion in a Constant-Volume Vessel, SAE paper 2010-01-0608, (2010).

DOI: 10.4271/2010-01-0608

[2] Bruneaux, G., Verhoeven, D. and Baritaud, T., High Pressure Diesel Spray and Combustion Visualization in a Transparent Model Diesel Engine, SAE Paper 1999-01-3468, (2009).

DOI: 10.4271/1999-01-3648

[3] Khalid, A., and Manshoor, B., Effect of High Swirl Velocity on Mixture Formation and Combustion Process of Diesel Spray, Applied Mechanics and Materials Vols. 229-231 (2012), Trans tech Publications, Switzerland, pp.695-699.

DOI: 10.4028/www.scientific.net/amm.229-231.695

[4] Khalid, A., Effect of Ambient Temperature and Oxygen Concentration on Ignition and Combustion Process of Diesel Spray,. Asian Journal of Scientific Research, 2013. pp.1-11.

DOI: 10.3923/ajsr.2013.434.444

[5] Okamoto, S., Shibamoto, R., Kidoguchi, Y. and Miwa, K., Effect of High Turbulence Mixing on Reduction of Exhaust Emissions from a DI Diesel Engine Employing EGR and Pilot Injection, Trans. of JSAE, Vol. 38, No. 2, pp.93-99, (2007).

DOI: 10.1299/jsmemecjo.2004.3.0_133

[6] Noge, H., Kidoguchi, Y. and Miwa, K., A study on NO Reduction Caused by Thermal Cracking Hydrocarbons during Rich Diesel Combustion, JSME International Journal, Series B, Vol. 49, No. 2, pp.526-532, (2006).

DOI: 10.1299/jsmeb.49.526

[7] Ogawa, H., Li, T., Miyamoto, N., Kido, S. and Shimizu, H., Dependence of Ultra-High EGR and Low Temperature Diesel Combustion on Fuel Injection Conditions and Compression Ratio, SAE Paper 2006-01-3386, (2006).

DOI: 10.4271/2006-01-3386

[8] Khalid, A., and Manshoor, B., Effect of High Swirl Velocity on Mixture Formation and Combustion Process of Diesel Spray, 2012 International Conference on Mechanical and Electrical Technology (ICMET 2012), pp.1-5, (2012).

DOI: 10.4028/www.scientific.net/amm.229-231.695

[9] Khalid, A., and Manshoor, B., Analysis of Mixture formation and Flame Development of Diesel Combustion using a Rapid Compression Machine and Optical Visualization Technique, International Conference on Mechanical & Manufacturing Engineering (ICME2012), pp.1-5, (2012).

DOI: 10.4028/www.scientific.net/amm.315.293

[10] Yatsufusa, T., Kawakami, J., Kidoguchi, Y., Khalid, A., Fujita, Y. and Omae, K., Effects of Supercharging, Swirl Strength and Fuel Injection Pressure on Development and Combustion of Diesel Spray, Trans. of JSAE, Vol. 40, No. 3, pp.755-761, (2009).

[11] Ikegami, M., Nakatani, K., Tanaka, S. and Yamane, K., Fuel Injection Rate Shaping and Its Effects on Exhaust Emissions in a Direct-Injection Diesel Engine Using a Spool Acceleration Type Injection System, SAE Paper 970347, (1997).

DOI: 10.4271/970347