废气再循环和添加剂对高辛烷值燃料HCCI燃烧的影响

本文对废气再循环(EGR)和十六烷值改进荆-过氧化二叔丁基(DTBP)对高辛烷值燃料HCCI燃烧的影响进行了研究。实验结果表明:辛烷值为90的燃料(RON90)只能在高温高负荷下才能运行HCCI燃烧模式;在其中加入少量的DTBP后,RON90实现HCCI燃烧的工况范围向低温低负荷下大幅度拓展。加入添加剂后,低负荷性能改善的同时,浓混合气的着火时刻可以通过EGR将含添加剂燃料的着火时刻推迟到上止点附近,从而大幅度提高热效率,降低了燃料消耗率。

EFFECT OF EXHAUST GAS RECIRCULATION AND CETANE NUMBER IMPROVER ON THE HCCI ENGINES FUELED WITH HIGH RON FUELS

The influences of cooled exhaust gas recirculation (EGR) and cetane number (CN) improver-di-tertiary butyl peroxide (DTBP) on the combustion phase and performance of the HCCI engines fueled with high research octane number (RON) fuels were studied in this paper. The experiments were performed using 0%, 1%, 2%, 3%, and 4% (by volume) DTBP-RON90 blends. The experimental results shown that the operation range was remarkably enlarged to lower temperature and lower engine load with the DTBP addition in RON90 fuel. With the improvement at the lower temperature and lower load by CN improver additives, the combustion phase of higher temperature and large load can be postponed to top dead center (TDC) by appropriated EGR rate. As a results, the indicated thermal efficiency and indicated specific fuel consumption (ISFC) was improved.