燃用二甲醚柴油机气道-气缸喷射复合燃烧  

Study on Compound Charge Compression Ignition Combustion in an Engine Fueled with Dimethyl Ether

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：《上海交通大学学报》2008年第3期370-374,共5页Journal of Shanghai Jiaotong University

基　　金：高校博士点基金(20050248013)资助项目

摘　　要：结合柴油机燃用二甲醚均质冲量压缩着火(HCCI)燃烧与缸内直喷燃烧各自优点,提出了气道-气缸喷射复合燃烧方式,并在一台柴油机上进行了试验研究.结果表明,燃烧过程包括二甲醚HCCI燃烧和缸内喷雾的预混及扩散燃烧,但随预混合率的不同呈现不同特征.随预混合率增加,在平均有效压力为0.12 MPa时,燃烧过程由两阶段发展到三阶段以至四阶段,再经三阶段回到两阶段,气缸压力、温度峰值先减后增,NOx排放单调减小;平均有效压力为0.24 MPa,压力、温度、压力升高率和压力升高加速度峰值以及NOx排放均先减后增;平均有效压力增为0.36 MPa时,最低和最高预混合率分别受到喷油泵供油能力和爆震限制,在能实现的预混合率范围内,压力、温度峰值和NOx排放随预混合率增加而单调增加.Combining the advantages of homogeneous charge compression ignition （HCCI） combustion and in-cylinder direct injection combustion for a diesel engine fuelled with DME, a new concept combustion system-compound charge compression ignition （CCCI） combustion by port introduction and direct injection of DME-was proposed,a diesel engine was modified to carry out this test. The results show that CCCI combustion process comprises HCCI combustion and pre-mixing combustion, diffusion combustion, but presents different combustion characteristic with the variation of premixed fuel ratio. With the increasing of premixed fuel ratio,at the brake mean effective pressure（BMEP） of 0.12 MPa,the combustion process develops from two stages to three stages and later evolves to four stages, finally returns to two stages combustion through three stages, the peak values of in-cylinder mean temperature, pressure decrease firstly and increase later,NO emissions decrease. At the BMEP of 0.24 MPa, the peak values of mean temperature, pressure,pressure rise rate and pressure rise acceleration as well as NO emissions decrease firstly and in- crease later;at the BMEP of 0.36 MPa, the peak values of mean temperature, pressure and NO emissions increase monotonously in the range of premixed fuel ratios.

关 键 词：二甲醚 复合燃烧 预混合率 柴油机 

分 类 号：TK46[动力工程及工程热物理—动力机械及工程]