摘要
在1台气道喷射单缸EGR发动机上,独立控制EGR缸喷油及点火,实现燃料改质,研究了不同压缩比对发动机性能的影响,此外还匹配了不同涡轮增压器,用于改善外特性扭矩。试验结果表明:单缸EGR能有效改善发动机的燃油经济性,NOx和CO排放性能均所改善,但THC排放恶化,动力性能下降;提高压缩比能有效提高发动机的热效率,降低燃油消耗,但过高压缩比使发动机爆震倾向严重,限制发动机外特性扭矩;通过匹配小涡轮增压器低速扭矩有所改善。
The effects of different compression ratios on engine performance were investigated on a single cylinder EGR engine by controlling the injection and ignition separately.Different turbochargers were matched to improve the full torque of each speed.The results show that the single cylinder EGR improves the fuel economy and NOx and CO emissions,but leads to the deterioration of THC emission and total power.Higher compression ratio can improve the engine thermal efficiency efficiently and reduce the fuel consumption,but too high compression ratio will increase the probability of engine knock and limit the torque of external characteristic.In the end,the torque at low speed improves by designing the turbocharger with a small turbine.
出处
《车用发动机》
北大核心
2017年第4期59-62,67,共5页
Vehicle Engine
关键词
汽油机
废气再循环
压缩比
热效率
gasoline engine
compression ratio
thermal efficiency
