Comparison of energy absorption characteristics of PCM-metal foam systems with different pore size distributions

Abstract

This paper presents a study on the effect of pore size on energy absorption characteristics of a PCM-metal foam energy storage system. Different metal foam geometries are generated by using a geometry creation model which considers the metal foam structure as a combination of overlapping spherical pores. The geometry creation model is coupled to an enthalpy-based phase change model to simulate melting. The main advantage of the model is that it can resolve the pore-scale structures of the metal foam and hence can capture the heat transfer between the PCM and metal foam accurately. The model is applied to analyze the effects of variation of pore size on melting and energy absorption characteristics by keeping the overall porosity constant. Simulation results show that, even for the same porosity, the pore size distribution strongly affects the rate of melting with smaller pores resulting in faster melting and higher heat transfer rate. This observation is found to be consistent for both low porosity and relatively high porosity systems. � 2019 Elsevier Ltd