缸内直喷汽油机冷起动参数研究及优化

Study and Parameter Optimization on Cold Start Phase of GDI Engine

在1台米勒循环增压直喷汽油发动机上,通过优化进排气可变气门正时系统(VVT)角度、喷油时刻、喷油压力和过量空气系数等参数,研究不同控制参数对发动机冷起动后催化器加热阶段排放的影响,得到最优的控制参数。在低温冷起动暖机阶段通过调整不同的喷油压力和喷油模式等,得到满足缸筒燃油“湿壁”评价要求的控制参数,以保证发动机的可靠性和排放性能。

The warm-up control strategies were achieved on a Miller cycle turbocharged GDI gasoline engine by investigating the influence of parameters,which includes EVO timing,IVC timing,SOI timing,injection pressure and lambda. The combustion chamber wet wall level and emission characteristics were evaluated by controlling influence of different injection mode and injection pressure.