直馏石脑油部分预混压燃的燃烧和排放特性  

Combustion and Emissions Characteristics of Straight-Run Naphtha in Partially Premixed Combustion Mode

作　　者：王金力[1,2] 杨福源[1,2] 欧阳明高[1,2] 

机构地区：[1]清华大学汽车工程系,北京100084 [2]清华大学汽车安全与节能国家重点试验室,北京100084

出　　处：《内燃机工程》2016年第5期1-8,共8页Chinese Internal Combustion Engine Engineering

基　　金：国家自然科学基金重点项目(51106086);国家"八六三"高技术研究发展计划项目(2012AA111705;2012AA111702;2011AA11A207)

摘　　要：在一台压缩比为17.5的柴油机上,研究了喷油策略和废气再循环(exhaust gas recirculation,EGR)对直馏石脑油部分预混压燃的影响。研究了三种部分预混燃烧喷油策略的影响,即一次喷射、固定时刻大比例一次喷射和小比例上止点附近二次喷射、50∶50的两次喷射(其中第一次喷射时刻固定)。三种喷射模式分别进行了二次喷射时刻和EGR的扫描试验研究。结果表明:三种喷射策略下都可以实现部分预混压燃,同时实现较低的指示比NOx排放和低的颗粒物排放水平。其中,单次喷射下需要辅以较大EGR率,燃烧热效率较高,最大压力升高率也较大。大比例预喷可以实现典型的部分预混合燃烧,热效率较高。50∶50比例喷射不需要大EGR率就可以实现低NOx和低颗粒物排放,但是整体热效率会受到影响,燃烧控制较困难。Experimental researches of the effect of injection strategy and exhaust gas recirculation（EGR） on partially premixed combustion of straight-run naphtha were carried out on a compression ignition diesel engine with compression ratio of 17.5. Three injection strategies were studied. The first injection strategy was single injection, the second injection strategy featured a large early injection with fixed timing followed by a small injection near top dead center, and the third injection strategy was similar to the second one in terms of injection timing, but with fuel split of 50∶50 for the two injections. Researches of injection timing and EGR rates of three injection models were carried out. Results show that all injection strategies may realize both low NOx and low particulate matter emissions simultaneously. The single injection strategy needs large amount of exhaust gas recirculation, resulting in higher indicated thermal efficiency, but the maximum pressure rise rate is also larger. The second injection strategy may achieve typical partial premixed combustion with higher thermal efficiency. The third injection strategy may realize low NOx and low particulate matter emissions without a large EGR rate, but with decreased thermal efficiency and hard combustion control.

关 键 词：内燃机 石脑油 燃烧 排放 部分预混燃烧 

分 类 号：TK421[动力工程及工程热物理—动力机械及工程]