关键词: 金属泡沫, 相变微胶囊悬浮液, 传热, 微通道, 数值模拟

Abstract: Micro-encapsulated phase change material slurry (MEPCMs) is a novel kind of functional thermal fluid, which has great potential in the field of electronic thermal management, thermal storage, etc. To improve the thermal management performance of high-power density electronic devices, a dual-enhanced heat transfer method with the combination of MEPCMs and metal foam was employed to improve the cooling performance of mini-channel heat sink in the present study. Numerical methods were utilized to investigate the heat transfer capability, flow resistance, and overall performance evaluation criteria (PEC) by considering the effects of MEPCMs mass fractions (5wt%, 10wt%, and 20wt%), inlet velocities, and metal foam filling ratios. The results indicated that the maximum temperature of metal foam mini-channel decreased and pressure drop increased with increasing the mass fraction of MEPCMs. At an inlet velocity of 0.06 m/s, increasing the mass fraction from 5wt% to 20wt%, the pressure drop increased by 2.09 times. 5wt% MEPCMs presented the best comprehensive heat transfer performance, and the PEC value was improved by 8.15%~12.18% compared with pure water. The filling ratio of the metal foam also significantly affected the heat transfer performance of the microchannel, and the cooling performance was best when the mini-channel was fully filled with metal foam. For the entire range of flow velocities, using 5wt% MEPCMs as the coolant, average Nuave of mini-channel heat sink fully filled with metal foam was 9.06 times of the empty mini-channel heat sink, and the pressure drop came to 56.91 times. With the comprehensive consideration of heat transfer enhancement and flow resistance, the PEC value could reach up to 2.61. The present findings could provide theoretical guidelines for developing more coefficient and compact liquid-cooled electronic devices.

Key words: metal foam, micro-encapsulated phase change material slurry, heat transfer, micro-channel, numerical simulation