Optimal design method for plate fin heat sinks subject to natural convection

Abstract

In this study, an optimal design method for minimizing the size of plate fin heat sinks subject to natural convection is proposed. An analytic model for predicting the thermal resistance of a fin array, as well as the heat sink substrate, is developed. In order to validate the analytic results, we performed numerical study and experimental studies. The results indicate that the proposed analytic model predicts the numerical and the experimental results well, within a maximum error of 5%. Based on the validated analytic results, we suggest an algorithm for minimizing the size of a natural convective plate fin heat sink subject to a constant thermal resistance. As the substrates thickness increases, the substrates conduction thermal resistance decreases while the convection thermal resistance decreases as the fin height increases. The minimum heat sink size is determined by a balance between those two competing effects. The minimum heat sink size is shown to increase as the heat source localization intensity increases.