基于相变微胶囊悬浮液的芯片阵列冷却特性研究

Study on cooling characteristics of chip array based on microencapsulated phase change material slurry

针对传统离散相模型(DPM)由于未考虑颗粒体积影响导致无法准确预测相变微胶囊悬浮液(MEPCMS)的压降,采用修正DPM模型,准确预测MEPCMS在芯片阵列中的流动传热特性,考察芯片发热功率及功率分布对冷却特性的影响规律。结果表明,MEPCMS相比于纯基液,平均Nusselt数Nu_(av)最高可提升30.03%,壁面温升ΔT_(w)最高可降低7.19%,综合性能评价因子η均大于1;芯片功率越高越靠近出口,悬浮液冷却效果提升越明显,高功率芯片靠近进口有利于抑制芯片的最高温升,靠近出口时悬浮液Nu_(av)的增幅大于摩擦因子和进出口压降的增幅,可见其受发热功率的影响较小,受功率分布的影响较大。为MEPCMS在细小通道内流动传热特性的认识及在电子器件热管理方面的应用提供参考。

In view of the fact that the traditional discrete phase model(DPM)cannot accurately predict the pressure drop of microencapsulated phase change material slurry(MEPCMS)because it does not consider the effect of particle volume,the modified DPM is used to accurately predict the flow heat transfer characteristics of MEPCMS in the chip array,and the influence of chip heating power and power distribution on cooling characteristics is investigated.The results show that compared to pure base liquid cooling,the suspension can increase the average Nusselt number Nu_(av)of MEPCMS by up to 30.03%,resulting in a maximum decrease ofΔT_(w)by 7.19%.The comprehensive performance evaluation factors of the suspension are all greater than 1.The closer the high-power chip is to the inlet,the more favorable it is to suppress the highest temperature rise of the chip.When a high-power chip approaches the outlet,the Nu_(av)increase of the suspension is greater than the increase in friction factor and inlet/outlet pressure drop.Therefore,it is obvious that it is less affected by the chip heating power and more affected by the chip power distribution.This work helps to understand the heat transfer characteristics and influence laws of MEPCMS in chip thermal management.