Melting and Heat Transfer Characteristics of Phase Change Material: A Comparative Study on Wire Mesh Finned Structure and Other Fin Configurations

In the present paper, a two-dimensional transient numerical study has been performed to investigate the influence of different fin designs on the melting and heat transfer characteristics of a phase change material (PCM), i.e., Paraffin wax, filled in square enclosures equipped with fin structures. Five distinct fin designs were examined: single rectangular, double rectangular, double triangular, double angled, and wire mesh. It is worth noting that all these fin designs have the equal heat transfer area. An isothermal heat source of temperature 350 K is provided at the left wall of the square enclosure and the remaining walls are assumed to be adiabatic. Six parameters were evaluated to determine the best fin configurations: melting time, enhancement ratio (ER), time savings, energy stored, mean power, and Nusselt number. The results show that all the fin designs outperformed as compared to model 1 (no fin configuration). Among the finned configurations, model 2 had the poorest performance, taking 1314 s to complete the melting, while model 6 had the most efficient fin design, with a melting time reduced by 67.53% compared to model 1. Model 6 also had the highest ER and mean power, i.e., 70.43% and 199.51%, respectively and as the melting process continued, the Nusselt number decreased. In addition to the above, we optimized the element size of the wire-mesh fin design using RSM methodology. This optimized design decreases the melting period by 70.04%. Overall, present study provides a comprehensive analysis of different finned configurations for improving the melting performance of the PCM in square enclosures and found wire-mesh fin design most appropriate and promising.