Influence of aspect ratios for a tilted cavity on the melting heat transfer of phase change materials embedded in metal foam

Abstract

We present numerical models to account for the transient free convection in the melted phase and heat transfer in porous foams filled in cavities with various aspect ratios. A visualization test-bed is set up, allowing for observing the solid-liquid interface and measuring internal temperature distribution. Simulation results are analyzed in terms of the melting rate, flow streamline and phase interface, temperature response, heat storage capacity and heat transfer performance. It is found that for a given aspect ratio, the inclination of the heating surface has a negligible influence on the melting rate, temperature uniformity, temperature response, and energy storage capacity for phase change materials in metal foam. However, for different aspect ratios, the case with a smaller aspect ratio (AR = 0.1) outperforms the one with a bigger ratio (AR = 8.0): a 4.96 and 15.85 times higher temperature uniformity and temperature response are achieved.