不同初馏点柴油对HCCI发动机燃烧和排放影响的试验

摘要

Experimental study was performed on combustion characteristics of HCCI engine in a modified six-cylinder turbocharged direct-injection diesel engine fueled with diesel of various initial distillation temperatures. Results show that HCCI operating range is narrowed with the decrease of initial boiling point. Operating range of fuels with initial distillation temperature of 125 ℃ and 100 ℃ are similar to that of pure diesel. Ignition delay increases with the lowering of initial boiling point which is beneficial to the improvement of mixing process with a penalty of decrease in indicated thermal efficiency. Without changing engine operating range, diesel wide distillation range reduces NOx and PM emissions, and meets the emission regulations. Utilization of wide distillation range fuel is a new way to optimize HCCI combustion.%在一台改装的6缸增压直喷式柴油机上进行了不同初馏点柴油均质压燃(HCCI)的试验.结果表明,在HCCI发动机上,随着初馏点的降低,运行范围有所下降,初馏点为125℃和100℃的燃料工况范围跟纯柴油相近,而滞燃期变长,有利于燃料的混合过程,但指示热效率会有所下降.在不降低运行范围的前提下,初馏点较低的燃油能很好地降低NOx排放,同时碳烟排放也有所降低,有利于满足排放法规的要求.拓宽燃油馏程为柴油机HCCI燃烧过程的优化提供新的途径.