空气强制对流冷却工况下多芯片散热过程数值模拟

Numerical simulation of heat dissipation for multiple electronic chips under forced air convection cooling conditions

建立强制空气对流冷却多个电子芯片的理论模型,采用控制容积法离散控制方程组并进行数值求解,得到芯片和固体基板的温度场,分析了冷却空气流过电子芯片的流场,同时在考虑芯片与基板的接触热阻的情况下,计算了芯片的温度分布,并与不考虑其接触热阻的数值模拟结果进行了比较。研究表明离冷却空气进口最远的芯片温度最高;空气在芯片之间流动会产生回流现象;当电子芯片与固体基板接触热阻较小时,芯片工作产生的热量能很好地通过固体基板传递出去,而当电子芯片与固体基板接触热阻较大时,热量传递会相对困难,使得芯片工作时产生的热量不能及时带走,芯片容易超温工作。

A theoretical model for forced air convection cooling of multiple electronic chips was developed,control volume method was used to discrete control equations solved numerically to obtain the chip and solid substrate temperature field. The flow field for cooling air flowing through electronic chips was analyzed,the temperature distribution of the chip was obtained in considering of the contact thermal resistance between the substrate and chip. The results were compared with the case without their contact thermal resistance. The study shows that the highest temperature appears to the chip which is furthest away from the cooling air inlet; air flow between the chips will produce reversed flow phenomenon. Without considering the thermal contact resistance between the electronic chip and solid substrate,the heat emitted by the chip can be well pass through the solid substrate; with considering the contact thermal resistance,heat transfer will be relatively difficult,and it cause the chip temperature to rise.