二甲醚发动机复合燃烧爆震特性  

Knock Characteristics of Compound Combustion in an Engine Fueled with Dimethyl Ether

作　　者：侯军兴[1] 乔信起[1] 王真[1] 刘炜[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：《上海交通大学学报》2009年第5期735-739,共5页Journal of Shanghai Jiaotong University

基　　金：高等学校博士学科点专项科研基金资助项目(20050248013)

摘　　要：将柴油机改造为二甲醚（DME）气道-气缸喷射发动机，研究DME复合燃烧缸内压力的频谱，探讨其爆震特性．结果表明：DME复合燃烧爆震频率带为5～10kHz；当转速增加时，爆震频率带及爆震段变宽；如果进气道喷射燃料中添加液化石油气（LPG），则爆震频率带及爆震段变窄，且接近上止点；将直喷燃料改为LPG，则爆震频率带变宽，爆震段变窄并接近上止点；当转速增加、进气道燃料添加LPG、直喷燃料改为LPG时，复合燃烧爆震时缸内压力的功率谱密度均增大．Experimental study on the compound combustion by port injection and direct injection of dimethyl ether （DME） was carried out on an engine retrofitted from a diesel engine. The spectrum of in-cylinder pressure of compound combustion was studied and the effect of major factors on knock characteristics was analyzed. The results show that the knock frequency band of compound combustion is between 5 and 10 kHz. With the increase of engine speed, knock frequency band and knock ranges become wider. Adding LPG into DME injected in the port, knock frequency band and knock ranges get narrower and are close to the top-dead-center. With the fuel injected in-cylinder replaced by LPG, knock frequency band becomes wider; while knock ranges get narrower and are close to the top-dead-center. As these factors change, the power density of in-cylinder pressure becomes larger.

关 键 词：二甲醚发动机 复合燃烧 爆震 

分 类 号：TK421.2[动力工程及工程热物理—动力机械及工程]