摘要
首先数值解析了缸内电控直喷汽油机的混合气形成过程,并且与光学纹影实验结果比较,验证了解析方法的可行性。在此基础上,分别考察了电控LPG直喷发动机曲面活塞顶燃烧室和凹坑型活塞顶燃烧室在部分负荷工况下混合气的形成过程。结果表明:在部分负荷下、压缩行程后期喷射时,由于缸内滚流的作用,两种不同形状活塞顶的燃烧室在接近压缩终了时,缸内混合气都能呈明显分层构造,即在火花塞附近聚集了较浓的混合气,而离火花塞较远处则是较稀的混合气,整个燃烧室的空燃比达到40∶1。
The mixture formation process of the direct injection engine is numerically analyzed. The model is then validated by comparing the simulation results with the results obtained by schlieren experiment. Based on the data, the feasibility of forming stratified mixture is investigated at part load for two types of chamber, one with a curving top piston crown and the other with a pit top piston crown, with the engine of MPI liquid phase LPG injection. The simulation results show that with the effect of tumble, at the late stage of eompression process, both chambers with different piston crown format obviously stratified mixture distribution with part load. That is, dense mixture is gathered around the spark plug meanwhile lean mixture far from it, and thus the air-fuel ratio of the combustion chamber comes to 40： 1.
出处
《山东建筑大学学报》
2009年第3期189-194,共6页
Journal of Shandong Jianzhu University
基金
国家自然科学基金项目(50576047)
清华大学汽车安全与节能国家重点实验室开放基金项目(KF2007-08)
山东省自然科学基金项目(Y2006F02)
关键词
液态LPG喷射
数值模拟
喷雾
liquid phase LPG injection
numerical simulation
spray
