Analytical and Experimental Investigation of Melting Heat Transfer

A computational model is presented for the prediction of the heat transfer between a heat-transfer fluid (HTF) and a phase change material (PCM) of a latent heat storage unit. Two models of flow, hydrodynamically fully developed and developing, of the HTF were proposed in this study. A two-dimensiona l enthalpy method was used for the computation of the phase change heat transfer in the PCM. A fully implicit finite-difference scheme was utilized for the calculation of convective heat transfer in the HTF. The unknown time-dependent boundary condition between the HTF and the PCM was found iteratively. The predictions were substantiated by their fair agreement with experimental data. Factors affecting the heat-transfer rates between the HTF and the PCM were studied numerically for both the hydrodynamically fully developed and developing flows. It was found that the Nusselt number is significantly increased by the developing temperature profiles. The developing velocity profiles also increased the Nusselt number. However, the influence on Nusselt number due to the developing velocity profiles was less significant than that due to the developing temperature profiles. Other factors affecting the Nusselt number are discussed.

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