电控喷油五气门汽油机排气再循环性能的实验研究

Effect of EGR on the Engine Performance of a Single Cylinder SI Engine with 5-Valves

以稀薄燃烧的汽油机电控喷油系统及排气再循环系统为实验平台,对可变进气五气门汽油机采用化学计量比时的排气再循环燃油经济性和排放性能进行了实验研究,结果表明,燃油消耗率明显改善(2.8%～5.5%),NOx显著降低(90%～95%),HC改善不明显.为了进一步挖掘稀燃发动机的低油耗和低排放性能,用稀燃运行时加入适量排气的方法,结果显示,NOx显著降低.

The effect of lean burn and exhaust gas recirculation (EGR) on a five-valve electronic controlled fuel injection engine are investigated. In order to improve the performance further, a way under the lean operating condition with EGR is adopted. This paper reports the results of an experimental study of EGR on exhaust emissions and fuel economy carried out on an experimental single cylinder engine with five valves and two swirl control valve. The results show that under stoichiometric operating conditions the application of EGR leads to a significant improvement in s. f. c. (2.8%-5.5%) at a moderate EGR rate and a large reduction in NOx(90%-95%) at a high EGR rate. The effect of EGR on HC is not appreciable. Under the lean burn operating condition with EGR, the NOx emission can also be reduced considerably.