A natural convection horizontal straight-fin heat sink design problem to enhance heat dissipation performance

Abstract

An optimized design for a three-dimensional natural convection horizontal straight-fin heat sink (SFHS) is numerically and experimentally examined in this study. The fin heights and shift displacement of the fins are considered as design variables, and this study aims to determine the optimal values of the design variables using the Levenberg–Marquardt method (LMM) to yield the minimum base surface temperature of the heat sink and thus enhance the heat dissipation performance of the system. Three design models (A, B and C) are examined, and the design parameters are considered to be the fin heights, the shift displacement of the fins, and both together. Numerical results show that the thermal resistance of designs A, B and C can be reduced by 5.7%, 14.4% and 15.6% compared to that of the original SFHS. These results imply that the shift displacement of the fin is a more effective design variable than the fin heights with regard to improving the heat sink's thermal performance. When both variables are considered as design variables, computational time increased tremendously, and the contribution of the fin height was trivial. Therefore, design B is recommended for practical application. Experiments were then performed on the manufactured original SFHS and design B heat sink to verify the validity of the optimal designs. Results showed that the error between the computed and measured base surface temperatures of the heat sink is small (less than 2%). The validity of using the proposed optimization algorithm to design the optimized shape of the natural convection SFHS is thus confirmed.