发动机活塞温度优化控制

Tempretures' Optimal Control of Engine Piston

活塞作为发动机极其重要的部件之一,由于工作环境非常恶劣,活塞温度随功率提高,热负荷增加。为控制温度,活塞头部涂敷热障涂层可以有效降低热量从活塞顶部向活塞裙部的传递,而不同的涂层结构对活塞温度和热应力有很大的影响。为了确定涂层材料的涂敷结构,采用Hypermesh和Abaqus有限元分析软件,分别计算了普通硅铝合金活塞、单一陶瓷涂层活塞和功能梯度热障涂层活塞温度场和热应力。研究不同梯度指数P对功能梯度热障涂层活塞温度场和热应力的影响,并综合分析得到最优梯度指数P=0.6。在考虑材料随温度相关性的情况下研究了P=0.6时活塞的温度场和热应力,结果表明P=0.6的热障涂层对活塞有很好的隔热效果。

Piston working in the worst working conditions is one of the important components of the engines. Thermal barrier coating coated on the piston head can effectively reduce the heat from the piston top to the piston skirt, and different coating structure has a great influence on the temperature and thermal stress. To determine the structure of the coating material, using the finite element analysis software Hypermesh and Abaqus, the temperature field and the thermal stress field of pure Si - Al alloy piston, pure ceramic piston and the functional gradient thermal barrier coating piston were calculated. The effect of different gradient index P on the temperature field and the thermal stress field of the functional gradient piston was researched, and the optimal gradient index P = 0. 6 was obtained by comprehensive analysis. In the condition of considering temperature dependence of material, the temperature field and the thermal stress of piston in P = 0. 6 was researched. The results show that the thermal barrier coating with P = 0. 6 has a good thermal insulation effect on pistons.