喷油比对复合喷射汽油机暖机过程燃烧和排放的影响

在一台复合喷射汽油机上进行了不同喷射方式的暖机试验,研究了不同的喷油比对复合喷射汽油机暖机过程中燃烧和排放特性的影响。结果表明,随着冷却液温度的升高,汽油机燃烧和排放性能逐渐改善,喷油比为80%时发动机性能最佳,与纯直喷相比,使暖机过程缸压峰值平均提高了49.1%,HC排放降低了14.5%,CO排放降低了27.1%,NO_x排放上升了56.6%,PN排放降低了92.5%。随着暖机过程冷却液温度的升高,发动机燃烧改善,HC、CO排放和微粒总数逐渐减少。

Effect of Injection Ratio on Combustion and Emission of Combined Injection Gasoline Engine During Warm-up Process

A warm-up test of different injection schemes is carried out on a combined injection gasoline engine to study the effects of different injection ratios on the combustion and emission characteristics of the combined injection gasoline engine in warm-up process.The results show that with the rise of coolant temperature,the combustion and emission performances of the gasoline engine gradually improve.When injection ratio is 80%,the engine achieves the best performance,with the peak of cylinder pressure increases by 49.1%,HC emission decreases by 14.5%,CO emission reduces by 27.1%,NO x emission rises by 56.6%,and PN emission lowers by 92.5%on average in warm-up process,compared with pure direct injection scheme.With the rise of coolant temperature in warm-up process,the combustion of engine improves,and the emissions of HC,CO and total particulates gradually reduce.