Analysis of melting and solidification processes in the phase-change device of an energy storage interconnected heat pump system

摘要

In this paper, an energy storage interconnected heat pump system is proposed. Numerical simulation is performed to investigate the melting and solidification processes of paraffin in a spherical heat storage unit. The influences of the spherical wall temperature, spherical heat storage unit size, and initial temperature of the phase-change material during the melting process, as well as the influence of the spherical wall temperature on the solidification process, were analyzed. The results indicated that the size of the spherical heat storage unit had the most dominant influence on the melting and solidification processes. The overall melting time was less than the overall solidification time at the same temperature difference. In the melting process, convective heat transfer invariably occurs between the liquid phase and the spherical wall, which accelerates the melting process.