柴油机受热零部件-冷却系统的流/热耦合仿真分析

Simulation and Analysis of Coupled Flow-Heat Transfer Model for Solid Components and Cooling System of Diesel Engine

建立了某D6114柴油机固件(机体、缸盖和缸套)和冷却系统的耦合模型,应用直接流/热耦合的方法对耦合莫型进行流动和传热的仿真分析,冷却水和冷却壁面间的热量交换由耦合计算自动完成,预测了该机冷却水套的流速分布和耦合体的温度场。数值模拟结果表明:机体水套的流场基本满足要求,而缸盖水腔各缸的流速分布存在明显差异,其中第一缸的局部区域流体速度最低(局部小于0.5m/s);受热部件的温度变化较大,差异明显,无论是缸盖、机体还是缸套,最大温度均出现在第一缸。

The coupled algorithm for flow and heat transfer was employed to simulate the temperature field of solid components and the flow distribution of water jacket in a in-line six-cylinder diesel engine by using STAR-CD software. Computation model includes cylinder block, cylinder liner, cylinder head, and water jacket. The effects of coolant flow on the temperature distribution of solid components were analyzed. The simulated results show that the flow distribution of water jacket on cylinder block meets demand, but that on cylinder head differs from six cyliners clearly, the velocity of the first cylinder head on exhaust side is less than 0.5 m/s and much lower than the other part; the temperature distribution of metal components varies from different parts, and the predicted highest temperature on solid components occurs in the first cylinder.