Melting and solidification of a PCM in a bottom-heated/cooled cavity with and without metal fins

In this research, a numerical investigation is conducted using COMSOL Multiphysics to examine both melting and solidification of the PCM lauric acid, placed in a vertical rectangular enclosure. The system is subjected to bottom heating and cooling, with or without metallic fins. The study focuses on evaluating the effect of the presence of metallic inclusion on the speed of the phase transition front and the consequent duration of the melting and solidification processes. The presented findings are the average liquid fraction over time, location of the phase change front, and temperature distribution within the cavity. The obtained outcomes highlight how different heat transfer processes, conductive and convective, are involved at various time instants during the PCM charging and discharging phases, as well as the heat transfer improvement yielded by the presence of metallic fins, which reduces the time needed for melting (solidification) by about 75% (86%). In addition, solid drops falling is observed when the horizontal melt layers spreading from the fin tops come in contact.