Numerical Investigation on Heat Transfer Enhancement with Perforated Square Micro-Pin Fin Heat Sink for Electronic Cooling Application

Abstract

In this paper, heat transfer enhancement through perforated square micro-pin fins (edge = 180 microns) has been analyzed through numerical simulation. A three-dimensional model has been developed on computational fluid dynamics (CFD) to study the effect of perforation number (One, Two and three) and shape of perforation (Circular and square) on the solid square micro-pin fin heat sink. The ratio of the perforation edge/diameter to the micro-pin fin edge is taken less than 0.375 that doesn't affect the conduction rate. The staggered array is considered for the arrangement of the perforated micro-pin fin on the heat sink due to non-overlapping wakes. Copper is used as a material of the fins and the heat sink. The flow of air and heat transfer characteristics are studied numerically on ANSYS Fluent for the range of Reynolds number ( $100\leq\text{Re} ). A constant heat flux $(\dot{Q}=50 \text{kWm}^{-} {}^{2})$ is applied at the bottom of the heat sink and an ambient temperature of 300K is considered. The size of the fins, the shape of the perforation and the number of perforation are counted as the prime geometric parameter for the calculation of most efficient heat sink. Thermal performance is calculated for every case and results are compared with the solid square micro-pin fins under the same working condition. Numerical results indicate that micro heat sink with perforation up to three gives better performance than the solid square micro heat sink, which shows that there is great potential to use perforated micro-pin fin heat sink for heat augmentation on electronic devices with high power density.