低压空气辅助缸内直喷汽油机工作过程仿真  

Simulation on Working Process of Low-pressure Air-assisted Direct Injection Gasoline Engine

作　　者：胡春明[1] 赖伟东[1] 侯圣智[1] 任立红[1] 

机构地区：[1]天津大学内燃机研究所,天津300072

出　　处：《农业机械学报》2013年第7期12-16,22,共6页Transactions of the Chinese Society for Agricultural Machinery

基　　金：国家高技术研究发展计划(863计划)资助项目(2008AA11A114);天津大学内燃机燃烧学国家重点实验室资助项目

摘　　要：对1.2 L低压空气辅助缸内直喷汽油机进行了工作过程仿真研究。分析了进气道及缸内的工质流动,比较了不同喷油时刻燃烧室改进前后在压缩上止点前20°CA时的缸内混合气浓度分布状况,探讨了点火时刻对发动机燃烧过程的影响。结果表明:压缩上止点前20°CA时缸内混合气浓度分布的整体均匀度要好于原机,且当喷油时刻为420°CA和440°CA时均能在两个火花塞间隙处形成适合稳定点火的混合气浓度;随着点火时刻的提前,燃烧逐渐提前,缸内最大爆发压力及最大压力升高率增大;此外,随着点火时刻的推迟,火焰发展期逐渐缩短,而快速燃烧期则呈现出先缩短后增长的趋势。The working process of a 1.2 L low-pressure air-assisted direct injection gasoline engine was studied based on simulation. The flow of working fluid in intake port and cylinder were analyzed. The cylinder mixture concentration distribution at 20° CA between the before and after improvement of combustion chamber under different injection timings were compared. The effect of ignition timing on engine combustion process was discussed. Results show that the overall uniformity of cylinder mixture concentration distribution at 20°CA is better than the original engine, and the mixture concentration for stable ignition could be formed in the two spark plugs gap with the injection timings of 420° CA and 440°CA. With the advance of ignition timing, combustion advances gradually, the maximum cylinder pressure and the maximum pressure rise rate increase. In addition, with the delay of ignition timing, flame development duration decreases gradually, while rapid burn duration decreases at the beginning and then increases.

关 键 词：缸内直喷汽油机 低压空气辅助 燃烧 仿真 

分 类 号：TK411[动力工程及工程热物理—动力机械及工程]