Simulation on Two-Stage Injection Combustion of Diesel Engine under Light Load

The objective of this paper was to simulate two-stage injection premixed spray combustion of common rail direct injection (CRDI) diesel engine using commercial CFD software code which called STAR-CD. Two-stage Injection with pilot and different injection dwell had been used to achieve premised combustion. And different intake temperature had been considered to control emissions. The model in this paper had been validated by experimental data. Two-stage combustion with lower NO and soot emissions were achieved by means of well mixed fuel-air mixture. As analyzed, optimizing injection dwell of two split main injection with pilot is able to decrease NO emission without fuel and soot penalty. Second main injection of two-stage fuel injection with pilot was set to 5° BTDC and 0 ° BTDC. Delay 2cd main injection is meaningful to NO drop while make soot emissions higher.