基于传热系数反求法的船用柴油机组合活塞热分析

Thermal Analysis of Composite Piston in Marine Diesel Engine Based on Inverse Evaluation Method of Heat Transfer Coefficient

建立了柴油机组合活塞的2D有限元模型,并利用传热系数反求法对该模型进行热分析。在仿真分析中,将活塞头部外表面传热系数定义为设计参数,实测温度与仿真温度的差值定义为目标函数。通过仿真计算得到了活塞头部外表面传热系数的分布,并利用反求法得到的传热系数对有限元模型进行热分析,仿真结果与实测温度吻合;传热系数反求法收敛迅速,可以有效用于活塞及其他内燃机零部件的温度分布和热负荷分析。

An axisymmetrical finite element model for composite piston of marine diesel engine was built up and used for thermal analysis of the piston by inverse evaluation method of heat transfer coefficient. Defined the convection heat transfer coefficients（HTC）on piston head surface as design variables, and the error between measured and predicted temperatures as objective function, the optimal HTC distribution on piston head surface was successfully determined using the inverse heat conduction method. The results show that simulated temperatures agree with the measured and the inverse evaluation method of heat transfer coefficient converges fast, it may be applied to temperature distribution and thermal load analysis of piston and other components in internal combustion engine.