Investigation of a graphite/paraffin phase change composite

Abstract Latent heat thermal storage of graphite/PCM composite was investigated numerically and experimentally. Graphite, as a highly-conductive, is an excellent candidate for forming thermal energy storage composites with improved effective thermal conductivity. For numerical simulation, the graphite/paraffin composite was modeled as a two dimensional system. Three modes of graphite addition were analyzed. Graphite was added as fibers, as fins or as foam. For every case, the thermal heat storage/release cycle is evaluated versus different graphite mass fraction. For experimental verification, the effective thermal conductivity of graphite/paraffin composites was measured using an electrothermal sensor based on a Wheatstone bridge. The results indicate a noticeable improvement in the effective thermal conductivity of composites compared to the PCM. The latent heat is measured using the differential scanning calorimeter (DSC). Our results are consistent with reported literature results.

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