Experiment And Numerical Simulation Of Thermal Contact Resistance

Thermal contact resistance means that when the surfaces contact with each other, in fact, the direct contact of solid and solid is only able to occur in a number of discrete points or small areas, and the different thermal conductivity of between the media space and solid generally changes the heat on the contact surfaces, then brings the additional resistance of heat flow. The work environment of spacecraft with a high Ma number is a high temperature and pressure air flow, and then the thermal contact resistance between spacecraft components is a key parameter of thermal response. The test of this performance and the explorations of factors relevant are very important.This study devises out an experiment program, manufactures a simple equipment of contact thermal resistance, collects and analyzes a number of contact resistance data. And then the effects of surface morphology and contact surface's temperature on thermal contact resistance are analyzed by using the finite element method.The experimental results show that the thermal contact resistance decreases nonlinearly as the temperature or the pressure increases and the values of thermal contact resistance with glue are larger than ones without glue.It can be seen from the simulation results that the thermal contact resistance takes a linear increase with the increasing average height of surface roughness and a nonlinear increase with the increasing ratio between non-contact area and nominal contact area. In addition, with the contact surface temperature increases, thermal contact resistance decreases.These findings will contribute to the design on the thermal structure of spacecraft and gathering some parameters relevant.