150柴油机活塞瞬态温度场分析

Analysis on the transient temperature field of a 150 diesel engine

为了探究活塞瞬态温度变化和活塞顶面的温度波动,以某150四冲程直喷柴油机活塞为研究对象,取一缸内燃烧过程详细分析活塞瞬态温度变化。利用映射的方式将周期性变化的边界条件通过傅里叶函数进行加载,计算得到初始阶段活塞顶面温度波动情况。研究结果表明,活塞由初始状态到稳定状态需要150 s左右,活塞顶面温升速率最大,最高温度为564 K;活塞顶面温度波动为7 K左右。活塞瞬态温度场数值计算结果表明,活塞满足热负荷要求。该研究可为同类型活塞设计优化提供参考。

In order to investigate the transient temperature change of the piston and the temperature fluctuation on the top surface of the piston,it takes a 150 four-stroke direct-injection diesel engine piston as the object,analyzes the in-cylinder combustion process and the piston transient temperature change.Based on the mapping method and Fourier function,it's loaded with boundary conditions that change periodically obtains the temperature fluctuations of the piston top surface at the initial stage.The results show that the time about 150 s for the piston reaches a stable state from the initial state,the temperature rise rate of the top surface of the piston is the largest with a maximum temperature of 564 K.The temperature fluctuation of piston top surface is about 7 K.The numerical calculation results of the transient temperature field of the piston show that the piston meets the thermal load requirements,which can provide a reference for the optimization of the same type of piston design.