FLOW AND HEAT TRANSFER ANALYSIS OF MICROCHANNEL HEAT SINK WITH SOLID INSERTS FOR ELECTRONIC COOLING APPLICATIONS

Abstract

The emerging field of electronic industry requires compact electronic components without sacrificing the reliability and performance of the equipment. The microchannel heat sink is the efficient liquid cooling technique to dissipate large heat flux in a miniature electronic component. In this study, the improvement in hydrothermal performance of conventional plane microchannel heat sink is analyzed by introducing different solid inserts in the channel flow path. A three-dimensional thin-walled rectangular microchannel with fixed aspect ratio and hydraulic diameter is considered for numerical analysis. The study aims to enhance the heat transfer by breaking the thermal boundary layer and decreasing the convective thermal resistance with small increase in pumping power. The coolant and solid insert used in the study are water and aluminum, respectively. Finite volume method-based solver ANSYS Fluent is used for simulating all cases. The effects of different inserts on fluid flow and heat transfer characteristics are analyzed for the Re number range of 500 ≤ Re ≤ 1000. The entropy generation minimization principle and performance index are the methods used for analysis. Based on the combined effect of flow and thermal characteristics, the insert with converging rectangular geometry gives the overall best performance. The optimum insert is further modified by varying the convergent angle in order to achieve a maximum possible heat transfer enhancement.