预混合比例实时优化控制正庚烷复合HCCI燃烧  

Optimizing Real Time Premixed Ratio of n-Heptane Compound HCCI Combustion

作　　者：马骏骏[1] 吕兴才[1] 吉丽斌[1] 黄震[1] 

机构地区：[1]上海交通大学动力机械及工程教育部重点实验室,上海200240

出　　处：《燃烧科学与技术》2009年第4期339-343,共5页Journal of Combustion Science and Technology

基　　金：国家重点基础研究发展计划(973)资助项目(2007CB210007);教育部博士点基金资助项目(20070248112)

摘　　要：在一台单缸柴油机上试验研究了预混合比例对正庚烷复合HCCI燃烧的影响,并在各个负荷下实现预混合比例的优化控制.结果表明:复合HCCI燃烧呈现三阶段放热模式,并且随着预混合比例的增大,复合HCCI燃烧第2阶段高温反应着火提前,燃烧持续期缩短,第3阶段扩散燃烧滞燃期缩短,同时缸内最高压力和最大压力升高率均升高.复合HCCI的NOx排放与直喷相比显著降低,且随预混合比例的增大先降低后升高.同时,复合HCCI的CO排放随预混合比例增大先增大后减小,而HC则随预混合比例增大而增大.通过预混合比例优化控制,复合HC-CI燃烧能够显著拓展负荷范围,并且保持较高的热效率.With the experiments carried out on a single cylinder diesel engine fueled with n-heptane, this paper investigated the effect of premixed ratio on compound HCCI combustion in order to achive optimization of premixed ratio at all loads. The test results indicate that compound HCCI combustion shows a three-stage heat release pattern. As the premixed ratio increases, the start of second-phase high-temperature HCCI combustion is advanced and the duration decreases. Meanwhile the ignition delay of third-phase diffusive combustion is shortened and both the peak cylinder pressure and the maximum pressure rising rate go up. Compared with the conventional diesel engine, the NOx emission of compound HCCI is reduced dramatically, and with the step-up of premixe ratio, it decreases at first and then increases. The study also reveals that the HC emission keeps increasing with the increase of premixed ratio, while the CO emission exhibites a rising tendency at first and then a descending trend. With the optimized premixed ratio, compound HCCI will largely expand the operation range without knock and maintain good thermal efficiency.

关 键 词：均质压燃 复合燃烧 正庚烷 

分 类 号：TK16[动力工程及工程热物理—热能工程]