Abstract
A method of analysis using an equivalent thermal conductivity of liquid phase is presented for the melting process of phase change material inside an isothermally heated horizontal cylinder. The equivalent thermal conductivity of liquid phase during the melting process was estimated from the results for natural convection heat transfer between concentric horizontal circular cylinders. The melting process was analyzed as a pure heat conduction problem by introducing the equivalent thermal conductivity of liquid phase. The present analytical results for the molten mass fraction show good agreement with the experimental data for a wide range of Rayleigh numbers. It was also shown that the effect of natural convection heat transfer on the melting process can be negligible for RaD < 105.
