复合相变热沉在电子设备热管理中的应用

摘要

某些特殊电子设备的短时高功耗运行往往会引起急剧温升,进而导致设备失效.文章采用膨胀石墨/高碳醇复合相变材料(PCM)作为热沉,针对某高功耗模块进行了散热仿真,并与传统铝热沉进行了对比,结果表明无主动散热平台下PCM热沉显著优于铝热沉.同工况温箱实验进一步验证相变热沉散热特性,并与仿真结果进行对比,结果表明实验结果与仿真结果具有一致的温度变化趋势,但由于相变温度范围的差异导致不同时间段温升速率不同.分析了二者的差异及原因,为严酷条件下应用相变材料进行热设计和热管理提供参考.%Some electronic equipment works in short time with high heat flux, which will cause a steep temperature rise that may even lead to equipment failure. In order to solve this problem, the expanded graphite/higher alcohol composite phase change material (PCM) is adopted in a high heat flux module. A comparison between PCM and Al as the heat sink material is made through simulation. It is shown that the PCM heat sink enjoys a superior thermal performance over the Al heat sink in the non-active cooling platform. A thermal experiment under the same condition is conducted to verify the superior thermal performance of the PCM and to make comparison with the simulation results as well. It is shown that both results have the same trend of temperature variation, but specific temperature change rates are observed for different phase change temperatures. The difference between the experiment and the simulation is analyzed, and the results may provide a basis for the thermal design and management using PCM as the heat sink under rigorous conditions.