EGR率对M15甲醇柴油燃烧与排放的影响*

Influence of EGR Rate on Combustion and Emissions of M15 Methanol-Diesel Blend

在不同工况下研究了不同EGR率对增压中冷柴油机燃用M15甲醇柴油混合燃料的燃烧和污染物排放的影响。实验结果表明:随着EGR的增加,最高缸压、最大放热率和缸内温度逐渐降低,所对应的曲轴转角后移,NOx排放大幅度降低,烟度、HC、CO等排放有不同程度的恶化。选择合适的EGR率可以消除柴油机NOx排放和烟度之间的Trade-off关系。

M15 Methanol-diesel blend fuel is applied in turbo-charged diesel engine at different working conditions,to study the influences of EGR rates on combustion and emission characteristics.The result indicates that the maximum cylinder pressure,heat release rate and temperature are all gradually reduced,the corresponding crank angle shift rearward.NOx emission is decreased by a large margin,while smoke intensity,HC and CO emissions are aggravated with different degree.The Trade-off relation between NOx and smoke intensity can be eliminated by choosing suitable EGR rates.