Optimization of Rectangular Fins Cooled by Forced Convection using Computational Fluid Dynamics

Abstract

The trends in electronics are toward decreasing size and cost, while increasing speed. Performance and reliability of operating devices can be achieved by increasing heat dissipated. As heat loads increase, the thermal management to keep junction temperatures within safe operating limits is becoming more critical. The heat sink optimization study allowed for a determination of the heat sink geometry, which would produce a minimum thermal resistance, while producing the highest heat dissipation. A flat plate heat sink with 50 mm x 58mm with different configurations was modelled using SolidWorks and a thermal analysis was performed. The result of the thermal analysis was used to optimize the fin geometries. The fin geometries considered are the pitch, fin height, numbers of fin and fin thickness. An Aluminium alloy was used as fin material to cool a motor driver (IRFP150N) with a heat power of 50W. It is found from the results that the best design with larger heat dissipation capacity is when fin thickness is small, wider pitch and taller fin height. And this consists of (7) fins with (0.3 mm) fin thickness and 7mm pitch.