发动机气缸盖冷却水流动试验及CFD分析

Experimental Research and CFD Analysis of the Cooling Water Flow in Engine Cylinder Head

针对高强化发动机气缸盖的冷却问题 ,采用流量压力测量法和染色剂法对透明气缸盖水腔进行了水流分布试验 ,得到冷却水在缸盖复杂水腔内的流场分布和水腔的流动阻力与进出水孔的流量 ,并对缸盖水腔不合理的地方加以改进 ;然后用FIRE软件对改进前后的缸套水腔冷却水流动进行数值模拟 ,得到冷却水在缸盖水腔内的三维流场 .将试验结果与CFD分析结果加以对比 ,表明水腔改进后流量和压力分布合理 ,微涡和流动死区减少 。

Aiming at the cooling of the compact engine cylind er head, the flow distribution test of the cooling water which flows in the chamber of the transparent cylinder head was performed by using the flux and pressure measurement and the coloring agent method. The 2D flow field of the cooling water in the complicated chamber was then obtained, and some improvement was made on the improper structure of the chamber. Furthermore, the 3D flow fields of the cooling water in the chambers of the actual cylinder heads before and after the improvement were obtained by means of the computational fluid dynamic (CFD) software FIRE. A comparative analysis was finally carried out between the test results and the CFD results. It is indicated that, after the improvement, the flux and pressure distribution in the water chamber is proper, and the eddy and dead zone decrease. Meanwhile, the flow direction and the flux of the cooling water obtained by the numerical simulation accord well with the experiment and observation results.