中文摘要：

以一台4缸柴油机为原机，在改造过的第4缸进行均质压燃（HCCI）燃烧试验，研究了混合添加剂对HCCI燃烧过程的影响。试验结果分析表明，在不同发动机转速、HCCI稳定燃烧工况下，混和添加剂均优于单一添加剂，即混合添加剂使得着火和放热提前，燃烧放热率峰值升高，并且发动机转速越高，混合添加剂对HCCI的燃烧影响越明显。此外，混和添加剂有助于改善高转速下HCCI发动机的失火，使得发动机在实验转速下工作平稳。

英文摘要：

The experimental research of homogeneous charge compression ignition （HCCI） combustion process with mixed additives was carried out by the modified fourth cylinder of a four-cylinder diesel engine. The influence of mixed additives on the HCCI combustion process was investigated. Experimental results indicate that the mixed additives are better than the single additive for HCCI fuel, causing ignition and heat release timings to be advanced and the peak of heat release rate to be increased at different engine speeds and steady operating conditions. Moreover, with the increase of engine speed, the influence of mixed additives on HCCI combustion is more obvious. In addition, mixed additives are beneficial to improving HCCI engine misfire at the high speed, and make the engine operating stable at specified speeds.