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

•The cooling performance of a tree-shaped fin submerged in a bio-based phase change material (PCM) is studied experimentally and numerically.•The melt fraction and the temperature of the heater are recorded over time for various heater power levels and orientations.•The experimental results showed that heating from the bottom resulted in the lowest heater temperatures.•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 in this study improve the fundamental understanding of fin based thermal management system when embedded in PCM.