Thermal Characteristics of Latent Heat Thermal Storage: Comparison of Aluminum Foam and Mesh Configurations

Abstract

The thermal characteristics of the phase change process due to three different configurations of the solution domain are studied using n-octadecene as a phase change material (PCM). The configurations include the PCM only, aluminum foam filled with the PCM, and aluminum mesh in the presence of the PCM. The time taken for the complete melting of the PCM is predicted for each configuration. In the analysis, the amount of PCM is kept the same for all configurations, and the amount of aluminum material is kept constant in the aluminum foam and the aluminum mesh configurations. The performance characteristics are the dimensionless temperature ratio ((T_max − T_b)/(T_max − T_in), where T_max is the maximum temperature, T_b is the bulk temperature, and T_in is the initial temperature), the minimum liquid fraction, the ratio of the cumulative energy stored during phase change over the total energy input to the storage system, and the total molten mass over the total mass of the PCM in each configuration. An experiment is conducted to verify the predictions of the numerical simulations for the aluminum foam. It is found that the experimental findings of the molten states of the PCM in the aluminum foam agree well with their counterparts predicted from the simulations. Aluminum mesh in the presence of the PCM significantly shortens the time required for complete melting in the thermal storage system.