点火室式直喷汽油机燃烧系统的研究Ⅱ:点火室内混合气形成过程  

Research on Combustion System of DISC Gasoline EnginesⅡ: Mixture formation process in the spark-chamber

作　　者：田江平[1] 隆武强[1] 西田惠哉[2] 张武[2] 

机构地区：[1]大连理工大学内燃机研究所,辽宁大连116023 [2]广岛大学喷雾与燃烧实验室

出　　处：《内燃机学报》2010年第4期309-315,共7页Transactions of Csice

基　　金：国家自然科学基金资助项目(50676014);国家"863"资助项目(2006AA110107)

摘　　要：介绍了点火室式直喷汽油机的工作过程,使用与点火室对称面具有相同截面形状的二维碰撞块进行了激光吸收散射法的试验,研究了喷射压力、环境条件、碰撞角度以及点火室深度对点火室内混合气形成过程的影响。在与试验相同的条件下,进行了碰撞喷雾的数值模拟,并使用试验数据对数值模拟中采用的碰撞模型进行了评价。试验结果表明:过大的碰撞角度会阻碍喷雾汽化过程;提高喷射压力可以加快喷雾汽化速度;近距离早喷射不利于点火室内混合气的形成;浅的点火室可以拖后喷射开始时刻,但会增大火花塞结碳的可能。计算结果与试验结果对比表明:目前常用的碰撞模型均不能在各个方面都与试验结果相吻合。Working process of the direct injection spark-chamber （DISC） gasoline engine is introduced. Laser absorption-scattering （LAS） experiments were conducted using the 2-dimensional impinging block which has the same cross section to that of the spark-chamber. Effects of injection pressure, ambient conditions, impinging angle and spark-chamber depth on mixture formation process were examined. Numerical simulation was conducted for the impinging spray under the conditions of experiments. Experimental resuhs were used to evaluate the wall interaction models in simulation. Experimental results showed that too large impinging angle could suppress the vaporization process, and a higher injection pressure would result in a higher vaporization rate. Early injection is inappropriate to mixture formation of spark-chamber and a shallower spark-chamber would retard the start of injection but increase the possibility of spark plug wetting. Comparison between simulation and experiment shows that none of the available wall interaction models agree with the experimental results of the impinging sprays.

关 键 词：点火室 缸内直喷汽油机 激光吸收散射法 数值模拟 

分 类 号：TK412[动力工程及工程热物理—动力机械及工程]