Thermal Management of Electronics During Continuous and Intermittent Operation Mode Employing Phase Change Material-Based Heat Sinks—Numerical Study

Transient numerical studies are performed for the effective medium of phase change material (PCM) filled with thermal conductivity enhancers (TCEs) for passive thermal management applications during continuous and intermittent operation. PCM melting and solidification were modeled using a simplified model assuming conduction-dominated heat transfer.
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-eicosane is used as the PCM, and copper is the TCE. Effect of aspect ratio (AR) is discussed for a continuous mode of operation. Different parameters like AR, power input, power ON- and OFF-time during intermittent operation are studied and discussed. We demonstrate the effect of these parameters on the thermal performance of the composite medium both during continuous and intermittent operation and discussion on the optimum volume fraction in different scenarios. Our results elucidate that, for any AR of the composite, the optimal PCM composite design in terms of volume fraction is primarily a function of the magnitude and duration of the pulsed load. Furthermore, a PCM usefulness merit is defined to understand the minimum amount of PCM required for safe operation under intermittent loading conditions.