喷油速度对活塞油腔瞬态流动传热的影响

Effect of Injection Velocity on Transient Flow and Heat Transfer in Pistongallery

活塞是发动机各个部件中的核心部件,且活塞处于高温环境下工作,因此活塞的冷却就显得尤为重要。增加活塞内冷油腔对活塞进行喷油冷却是降低活塞温度、改善活塞运行工况最为有效的方法。由于活塞在实际工况中是处于运动状态,因此需要采用瞬态计算。本研究主要利用ANSYSFLUENT软件对活塞喷油冷却进行数值模拟,研究了不同的喷油速度下活塞内冷油腔中冷却油的体积分数,油腔内冷却油的相对运动速度,油腔的边界传热量的变化规律。从而得出活塞喷油速度对油腔传热边界的影响规律。利用得到的规律可以为内燃机的设计提供合理的建议与解决方案。

The piston is the core part of the engine components,and the piston works in high temperature environment,so the cooling of the piston is particularly important.It is the most effective way to reduce the temperature of the piston and improve the working condition of the piston by using the cooling gallery.Because the piston is in motion at the actual working condition,so the transient calculation is needed.In this study,ANSYS FLUENT software is used to simulate the injection cooling of the piston.The volume fraction of cooling oil,the relative movement speed of the cooling oil in the piston gallery and the heat transfer at the boundary of the piston gallery are studied under different injection speeds.The influence law of cooling oil injection speed on heat transfer boundary of pistongalleryis obtained.The obtained rules can provide reasonable suggestions and solutions for the design of internal combustion engine.