Evaluation of phase change material melting process in an energy storage chamber with porous metal foam gradient and discrete strip fins

Abstract

In this research, the process of melting the phase change material (PCM) in a thermal energy storage chamber with the discrete strip fins, metal foam gradient, spatial, and temporal changes in the wall has been investigated. The efficacy of geometric parameters, fin arrangement and fin material on the melting process has been explored. RT82 is considered as the PCM. Temporal changes in wall temperature in both step and sinusoidal modes are considered. To simulate the liquifying-freezing process, the porosity-enthalpy method base on the finite volume method is applied. The outcomes display that in various cases of the study, the result shows that the number of fins affects the melting time. The melting time for discrete fins is reduced by about 50 % compared to continuous fins. The outcomes indicate that the melting fraction rate is improved in the step mode compared to the constant temperature mode. In the sinusoidal state, the infiltration of wall temperature fluctuations into the melting fraction is observed and the melting fraction value is fixed around a value after a specific time. The spatial distribution of wall temperature influences the melting time. The parabolic temperature distribution with location provides about 42 % improvement in the melting process compared to the constant temperature state. The effects of positive and negative porosity gradients in three spatial directions on the melting process and energy storage have been explored. The porous medium and the change of its porosity coefficient are effective on the melting process and the melting time is reduced by about 90 %.