Forced Convection Heat Dissipation from Pin Fin Heat Sinks Modified by Rings and Circular Perforation

The primary factors to be managed in the design of heat sinks include enhancing the heat dissipation rate, minimizing occupied volume and mass, and eliminating lower heat transfer areas behind the pin fins. This study focuses on numerically analysing the impact of combining perforation technique and ring inserts on the heat dissipation and turbulent fluid flow characteristics of pin fin heat sinks. The rings are positioned around the cylindrical pin fins (CPFs). The perforation technique allows fluid flow to pass through the pin fins (PFs) and agitate the stagnant zones of flow behind PFs. These configurations are denoted as case 0 (no perforation) to case 4. Results show that fitted with rings and perforation (case 4), as an optimal configuration, demonstrates a 180.82% increase in Nusselt number and a 154.54% decrease in thermal resistance compared to CPFs. Fortunately, this configuration contributes to a significant decrease in the pressure drop by 62.19%. Furthermore, under the same conditions, the occupied volume and mass of case 4 are reduced by 77.5% and 77.65%, respectively. Additionally, the optimal configuration exhibits the highest hydrothermal performance factor (eta) of 3.29 at Re = 8740.