Incorporation of Horizontal Fins into a PCM-Based Heat Sink to Enhance the Safe Operation Time: Applicable in Electronic Device Cooling

Abstract

In this study, the effect of the presence of horizontal fins on the safe operating time (SOT) of the PCM filled heat sink was examined. The effects of the number of horizontal fins, as well as fins length on SOT at different aspect ratios, was investigated. Horizontal fins, owing to their high thermal conductivity, cause uniformity in temperature distribution and improve the heat sink thermal conductivity (positive effect). Incorporating horizontal fins reduces the PCM volume fraction which consequently diminishes the ability of the heat sink to absorb the thermal energy (negative effect). The competition between the former effect and the latter determines the efficacy of adding horizontal fins in the PCM filled heat sinks. As the number of horizontal fins increases up to five, the positive effect is superior to the negative one which in turn enlarges the safe operation time. By the further increase in the number of fins, the negative effect prevailed over the positive effect and therefore the safe operation time diminished. As the heat sink aspect ratio increased, convection heat transfer efficacy becomes more apparent. In this case, it is recommended to use horizontal fins with shorter lengths so that the PCM movement is not disturbed.

Keywords

• PCM-based heat sink
• safe operation time
• horizontal fin
• aspect ratio