基于多点接触理论建立了高温接触热阻的计算模型及其有限元格式,模型的基本尺寸取自表面粗糙度测量时的特征尺寸,该模型能有效模拟界面粗糙度、界面压力、界面温度和间隙填料热导率等参数对界面接触热阻的影响,同时也考虑了高温环境下材料热导率随温度变化的特点以及通过界面间隙的辐射换热效应。在此基础上,针对影响接触热阻的若干主要参数进行了研究。数值算例表明:该文所建立的有限元计算模型及其计算方法不仅能有效地模拟不同条件下高温接触热阻的变化规律,也为进行高温接触热阻研究提供了一种新途径。
The computational model and a finite element algorithm for high temperature thermal contact resistance analysis are established, based on the multipoint contact theory, and the basic parameters of the computational model can be derived from the characteristic sizes of surface toughness measurements. The present model can simulate the effects of interface toughness, interface pressure, interface temperature and the property of interstitial materials to the thermal contact resistance, with the consideration of temperature-dependent thermal conductivity under high temperature and the radiation heat transfer effects in the interface gap. Numerical results show that: the present finite element model and computational method can simulate the thermal contact resistance under different conditions, and it is a new approach to high temperature thermal contact resistance research.