Introducing a novel heat sink comprising PCM and air - Adapted to electronic device thermal management

With the introduction of PCM-based heat sinks, the cooling of the electronic components in transient applications has been developed. The PCM-based heat sink effectiveness is acceptable only within the melting time, so that in the post-melting stage, the electronic component temperature increases significantly. In this study, a novel hybrid heat sink filled with PCM and air was introduced. This heat sink uses the PCM and air potentials simultaneously to neutralize the effects of the incoming heat flux to keep low the electronic device temperature. Incorporation of air into the PCM-based heat sink leads to acceleration in the heat rejection to the ambient (positive effect) and reduces the PCM volume fraction (negative effect). Based on the results, the positive effect outweighed the negative one and consequently, the cooling ability of the novel heat sink was better than the PCM-based as well as air-cooled heat sinks. As the convective coefficient increases, the positive effect strengthened and hybrid heat sink effectiveness become more apparent. It was found that the novel heat sink (with 50 W.m−2.K−1 ) can compete with air-cooled heat sinks with much higher convective heat transfer coefficient (100 W.m−2.K−1 ) .