Experimental study on the performance of a compact heat sink for LSI packages

Abstract

The cooling performance of compact heat sinks composed of small fins, investigated in conditions of both natural and forced air convection, should also be explored in designing the heat sink on an LSI package. An experimental study was performed with respect to natural air convection and forced air convection. Several kinds of compact heat sink which have different base areas, fin intervals and fin heights were heated by an attached electrical heater, which could supply a specific heat flux. The increase in fin temperature was measured by small thermocouples. In natural air convection experiments, the effect of the supplied wattage on the temperature rise of the heat sink was examined for different fin intervals and fin heights. In forced air convection experiments, a wind tunnel was used. The heat sink was set downstream in the wind tunnel and a specific heat flux was applied to it. The correlation between supplied air velocity and temperature rise in the heat sinks was explored. Furthermore, from these results, non-dimensional expressions to evaluate the cooling performance of compact heat sinks were examined.