Effect of fluid distribution on the cooling performance of hybrid microchannel and slot-jet impingement system

Abstract

Hybrid microchannel heat sink and slot-jet impingement system (MCSJ) is favored by researchers for its advantages in the cooling of high-heat-flux electronic device. In this study, the effect of fluid distribution on the hydraulic and thermal performance of MCSJ is numerically investigated with a realizable k-ε turbulence model. Firstly, the influence of the cooling water entrance position on the turbulent flow and heat transfer characteristics of MCSJ was studied. It is found that the MCSJ-2 exhibits the best cooling performance. Compared with the conventional design (MCSJ-5), when the inlet water velocity was set as v = 6 m/s, 8 m/s, and 12 m/s respectively, the total thermal resistance of MCSJ-2 decreased by 2.43 %, 2.07 % and 0.71 %, correspondingly; and the temperature difference of the bottom surface in MCSJ-2 decreased by 11.08 % (v = 6 m/s), 6.86 % (v = 8 m/s), and 4.99 % (v = 12 m/s), respectively. Measures to improve the uniformity of fluid distribution among the microchannels in MCSJ-2 were then analyzed. The results show that inserting fin-ribs in the distribution chamber of MCSJ-2 can effectively decrease the pressure drop and improve the thermal uniformity performance of the hybrid system. The fin-ribs’ height and length have different effects on the hydraulic and thermal performance of MCSJ-2.