Effect of Split Injection Pattern on Combustion and Emission Characteristics of D.I. Diesel Engine

-3rd Reprot : Effect of Injection Interval

Abstract

Effects of the split injection pattern on combustion and emission characteristics of a D.I. Diesel engine with a common-rail injection system were investigated. While keeping the injection pressure and total injection quantity constant, a ratio of amounts of fuel injected between two injection pulses and the injection interval were varied. The in-cylinder pressure was analyzed, and the characteristics of the combustion process were discussed with the engine-out measurements. The concentration distributions of the vapor and liquid phases in the splitting fuel spray injected into a high-pressure/high-temperature vessel were measured by means of the Laser Absorption Scattering (LAS) technique. The mixture properties obtained by the LAS measurements were correlated with the characteristics of the combustion process. The results account for the effects of the split injection pattern on the combustion and emission characteristics.