发动机复合材料连杆传热的无网格模型与应用

Meshless Model and Application for Heat Transfer of Engine Composite Materials Connecting Rod

利用无网格伽辽金法(Element-free galerkin,EFG)建立了发动机复合材料连杆的传热计算模型,推导了正交各向异性结构的无网格法传热控制方程,通过复合材料平板验证了该模型对混合边界条件传热问题有很好的适应性。利用EFG法计算了不同各向异性因子的复合材料连杆的温度场,并讨论了EFG节点数对精度的影响。结果表明,EFG法的温度计算精度比有限元法高,且各向异性因子小于1时能较好地改善连杆小头的温度场分布,连杆设计时宜选择横向导热系数比纵向大的复合材料。

A calculation model for heat transfer analysis of internal combustion engines composite materials connecting rod was established with the element-free galerkin （ EFG ） method, and the heat transfer governing equation for the orthotropic structure based on the meshless method was deduced. The numerical example of composite materials plate was used to verify that the meshless model has a good adaptability for the heat transfer problem under the mixed boundary conditions. The temperature field of the composite materials connecting rod with different anisotropy factor was calculated with EFG method, and the effect of the EFG node number on the calculation accuracy was discussed. The result shows that the temperature based on the EFG method has a higher accuracy than that via FEM, and the temperature distribution of connecting rod small end can be greatly improved when the anisotropy factor is less than 1. The composite materials with the transverse thermal conductivity more than the vertical should be chosen for designing the internal combustion engines connecting rod.