Effectiveness Study of Streamlined Fin with Low-Pressure Loss to Improve Heat Dissipation Performance of Heat Sink

In recent years, with the advent of next-generation semiconductors, circuit boards have been miniaturized to accommodate higher frequencies. Miniaturization also means increased heat density. Further miniaturization of switching converters and inverters requires heat sinks that provide excellent heat dissipation performance in a limited volume, and the cylindrical fin type has been commonly used as a heat sink structure. However, cylindrical fin type heat sinks have the problem of large pressure loss when refrigerant passes through them. To solve this problem, streamlined fins and elliptical fin have been proposed to replace cylindrical fin type heat sinks. Although many studies have compared the heat dissipation performance of elliptical and cylindrical fin, few studies have compared it with that of streamlined fins. Therefore, in this paper, a heat sink structure with multiple streamlined fins is constructed. The change in pressure loss due to the change in fin shape and the resulting heat dissipation performance were verified by thermo-fluid analysis and actual device verification, and compared with the conventional cylindrical fin type. As a result, it was confirmed that the streamlined fin structure slightly increases thermal resistance and significantly reduces pressure loss. Comparison of the thermal resistance-pressure loss characteristics showed that the streamlined fins can sufficiently reduce the pressure loss for the same thermal resistance value. In the case of forced air cooling, the heat dissipation performance of the streamlined fins could be expected to improve with fan selection.