Thermal and hydraulic performances of the wavy microchannel heat sink with fan-shaped ribs on the sidewall

Abstract

The innovative wavy microchannel heat sinks with a variety of geometric fan-shaped ribs are proposed. The thermal and hydraulic performances of such a microchannel are given considering the thermo-physical properties. The calculation results validate its advantage in improving the thermal performance. New insights into the flow and heat transfer mechanism are obtained based on the detailed flow field evolution. The geometry parameter of fan-shaped ribs on the friction factor, Nusselt number, and thermal performance is further investigated. Results show that the heat transfer enhancement is dependent on the geometric parameters of ribs and Re. Compared with rectangular wavy microchannel, the heat transfer is enhanced in the larger Re besides Hr/Wr = 0.05. The best thermal performance of this proposed microchannel is mainly observed at the Sr/Wr = 2, and a worse thermal performance is found for the microchannel as the Sr/Wr = 1 and 4 in the lower Re. With the increase of the flow rate, a noticeable increase in PEC is found for the heat sinks with lower Sr/Wr. The maximum value of PEC occurs more early for the channel with Sr/Wr = 0.0375, and the increase rate of PEC for such microchannel with Re is lower. The PEC is larger for Hr/Wr = 0.1125 and 0.075 in the higher Re.