直喷式发动机喷雾模型研究进展

雾化是在点火之前喷射燃油与环境因素发生复杂的物理作用的结果。本文从雾化过程喷嘴内流动、射流破裂、油团破裂、油滴蒸发四个阶段着手，在考虑到雾化过程中所伴随的减速、变形、扩散、缸壁油膜形成、油滴之间碰撞以及油滴与缸壁碰撞等物理现象基础上，综合对比了国际上近年来用实验分析方法所建立的各种相应计算模型的特点、应用情况及不足。分析了选择子模型组合并集成在计算模型(KIVA)中对缸内喷射对象的雾化过程模拟的可行性。最后结合计算机技术的发展指出了雾化过程模拟发展趋势。

Development of Spray Model in Direct Injection Engines

The fuel atomization is the result of injected fuel acting on the environments physically before ignition. The main atomization process can be divided into four stages namely the fuel flow in an injection nozzle, the spray break, the fuel group break and the fuel drop evaporation. The characteristic,application and demerits of some typical sub-procedures from the four stages of the atomization process were compared and analyzed based on the phenomena of deceleration, deformation, diffuse, fuel film forming on the cylinder wall, the fuel drop hitting with each other and on the cylinder wall in those process. The feasibility of the integrating of those sub-procedures into the KIV fuel spray process was analyzed. The spray model progress was pointed out at the end of this paper.