Numerical and experimental investigation of the melting of a PCM in an enclosure having a tree-shaped internal fin

Phase change materials (PCMs) have been proven to be effective for many thermal management and energy storage applications. The performance of PCMs can be increased further by adding filler materials; for example, metal foam, metal particles, and heat sink. The main objective of this study is to investigate the enhancement of melting process of PCM in the presence of nature inspired geometry, such as, tree-shaped fin. The aluminum treeshaped heat sink is submerged into a biobased PCM (coconut oil). The variables considered in this study are orientation of the heater and the power supplied to the heater. Heat is supplied at a constant rate at various levels from the top, side, and bottom of the enclosure to study the effect of natural convection on melting. The melt fraction and the temperature of the heater are recorded over time for various heater power levels. Two dimensional numerical simulations using COMSOL Multiphysics software on a rectangular cross section of PCM are conducted as well. The experimental results showed that heating from the bottom resulted in the lowest heater temperatures and heating from the top resulted in the highest temperatures with heating from the side in between. There is a 17 % reduction in heater temperature when heating from the side and a 23 % reduction when heating from the bottom relative to heating from the top for a specified heat flux value of 7.3 W. The numerical results show that because of natural convection, heating from the bottom helps to keep the heater surface to the lowest temperature. Results presented here improve the fundamental understanding of fin based thermal management system when embedded in PCM.