Effect of installing rings on the cooling performance of a pin fin heatsink

Although many studies have improved the performance of heatsinks for dissipating heat in high-heat-generating electronic devices such as LED lightings, most have focused on developing new designs or adding structures to enhance the chimney effect. In this study, to improve performance without replacing the existing heatsinks in use, installing simple rings on pin fins was considered. Diameter, thickness, and installation position of the rings were optimized using the Box-Behnken design. The optimized ring-added heatsink was fabricated, and heatsink's thermal resistance was measured over an installation angle range of 0°–180°. Good agreement between experimental data and simulation results was observed, with an error of less than 5.36 %. The installation of rings on pin-fins increased airflow between the fins, resulting in increased average airflow velocity and improved uniformity of airflow velocity within the heatsink. The optimized ring-added heatsink consistently demonstrated better cooling performance compared to the reference pin fin heatsink without rings within the considered installation angle range, showing a notable 15.3 % decrease in thermal resistance at an installation angle of 0°. It is expected that effective performance improvement can be achieved in various fields without replacing the existing air-cooled pin fin heatsinks currently in use, simply by installing rings.