Paper presented at the 9th International Conference on Heat Transfer, Fluid Mechanics and Thermodynamics, Malta, 16-18 July, 2012.
In this study, the thermo-flow characteristics of pin-fin radial heat sinks were investigated according to their fin height profile. A pin-fin radial heat sink is composed of a horizontal circular base and rectangular pin fins. Pin-fin radial heat sinks with differing fin height profiles were examined so that one could be designed for large-output light-emitting diode (LED) products using the same heat sink mass as reported for previous plate-fin heat sinks. Both natural convection and radiation heat transfer were considered in the investigation. The thermal resistances of heat sinks with various types of pin-fin arrays were compared to determine an appropriate reference configuration. A parametric study was then performed to compare the effects of five geometric parameters (outermost fin height, difference between fin heights, number of fin arrays, long fin length, and middle fin length) on thermal resistance. The effects of the outermost fin height and the number of fin arrays were found to be significant.