内外部EGR控制二甲醚发动机的燃烧与排放  

Combustion and Emission Control in DME Engine Using Internal-External Exhaust Gas Recirculation

作　　者：张俊军[1] 乔信起[1] 王真[1] 管斌[1] 黄震[1] 

机构地区：[1]上海交通大学动力机械与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5期435-439,共5页Journal of Combustion Science and Technology

基　　金：高校博士点基金资助项目(20050248013)

摘　　要：在一台改造过的2-135柴油机上通过气道引入二甲醚和CO2,模拟实现了内外部EGR控制二甲醚发动机燃烧与排放的试验研究.结果表明,燃烧过程包括二甲醚HCC I燃烧和缸内喷雾的预混及扩散燃烧;燃烧方式主要受内外部EGR率的影响而呈现不同的放热特征.缸内直喷燃烧采用较大供油提前角时,在较小内外部EGR率下可使NOx排放控制在50×10-6以下;在较小供油提前角和微量内外部EGR率下可实现二甲醚发动机两级预混合低温燃烧模式,NOx排放接近于零.采用适当的内外部EGR率,二甲醚发动机经济性与NOx排放可获得较好的折中.A 2-135 CI engine was modified to carry out the test for combustion and emission control using internal-external exhaust gas recirculation（EGR） by port aspiration and in-cylinder injection of dimethyl ether （DME）. The results show that the overall combustion process comprises HCCI combustion, pre-mixing and diffusion combustion, and that the combustion characteristic is mainly decided by internal-external EGR rate. The results also show that at an ear/y fuel delivery advance angle, NOx emissions can be lowered to around 50 × 10^-6 with the help of a little internal-external EGR rate. It is interesting to note that, at a small fuel delivery advance angle, two-stage pre-mixing low temperature combustion can be obtained using a low internal-external EGR rate, and NOx emissions can be lowered to nearly zero. A good compromise for DME fuel consumption and engine-out NOx emissions can be achieve in a DME engine using an appropriate internal-extennal EGR rate.

关 键 词：二甲醚 废气再循环 均质充量压燃 预混合率 CO2进气率 

分 类 号：TK46[动力工程及工程热物理—动力机械及工程]