Numerical study on hydrothermal performance in a microchannel with gradient array of ribs and pin fins

An innovative microchannel heat sink (MCHS-GDRPF) with gradient array of ribs and pin fins is proposed to address the heat thermal management of high heat flux densities and ensure temperature uniformity. This heat sink combines the cooling advantages of ribs and pin fins, with the structural dimensions of the ribs and pin fins increasing linearly along the flow direction. Three-dimensional numerical simulations are utilized to assess the impacts of different gradient array patterns, relative rib-pin fins diameter and height on hydrothermal performance and temperature uniformity. Additionally, a comprehensive comparison of hydrothermal performance between the MCHS-GDRPF and four other microchannels with similar structured arrangements is presented. The results show that at a Reynolds number of 622, the surface temperature of the heat source is reduced by 28.59 K, temperature uniformity is improved by 73.4%, the Nusselt number exhibits a 195.1% enhancement, and the performance evaluation criterion (PEC) attains a value of 1.366. Overall, this structure effectively ensures temperature uniformity and enhances heat dissipation capacity.