热锻温度场接触换热系数测试方法

Investigation for measuring heat transfer coefficient on contact surface of hot forgings

基于能量守恒定律,提出一种高温、塑性变形条件下固体接触换热系数的测试方法。以此为基础,开发试制了一套不同接触条件下的固体接触换热系数的测试系统。设计了合理的实验方案,并利用该测试系统测试了H13钢与SA508-3钢在不同初始界面温差、接触载荷下的接触换热系数。研究实测结果发现,在高温下(900℃以上),接触换热系数随着接触载荷增大而增大,且呈现较好的幂律关系;初始界面温度对接触换热系数影响较小;初始界面温差对幂指数的影响较小。实测温度数据与数值模拟数据相吻合,表明该测试系统具有较好的精度与可靠性,具有工业实用价值。

Based on the energy conservation law,a new method to measure the contact heat transfer coefficient（CHTC）on the contact surface of hot forgings is presented.A device which can measure the CHTC under different contact conditions is designed and manufactured according to this new method.The transient contact heat transfer processes under different initial temperatures and contact pressures between the H13 and SA508-3steel were investigated by the self-developed measuring apparatus.The measuring results indicate that the CHTC increases with the increase of contact pressure at high temperature（above 900℃）.The relationship between the CHTC and contact pressure follows the power-law correlation,which is independent from the initial contact temperature.Finally,the measured temperature on the typical points was compared with the simulated temperature,and the two results of temperature showed a well agreement with each other.The results indicate that the measuring system is reliable and has the application potential in the industry.