Numerical Investigation of Phase-Changing Material Filled Shell and Tube Heat Exchanger with Fins

The efficient utilization of thermal energy storage (TES) systems depends significantly on the choice of phase change materials (PCMs) and the employed heat transfer mechanism. PCMs used in TES systems often exhibit poor heat transfer rates due to their low thermal conductivity. Improving the heat transfer rate between the heat transfer fluid (HTF) and PCM is crufigcial to capture a larger amount of energy during the PCM's phase change. When PCMs with low thermal conductivity are selected, it becomes essential to enhance their performance. Various research studies have focused on improving the thermal conductivity of PCMs, including the implementation of different fin geometries. Fins can enhance the heat transfer rate between the HTF and PCM, thereby reducing the melting time of the PCM. T-shaped fins have been considered as a feasible option for analysis in computational fluid dynamics (CFD) studies due to their reliability, cost-effectiveness, and ease of fabrication. The present study employed ANSYS FLUENT CFD software to numerically examine the improvement of thermal performance in a shell-and-tube heat exchanger (STHX) through the utilization of T-shaped fins. These novel fin shapes were suggested to improve the melting rate of the phase change material (PCM) within STHX. The thermal performance of the T-shaped fin was compared to that of the traditional longitudinal fin shape, considering the same dimensions and PCM material. The analysis included two types of heat exchangers: one equipped with four longitudinal fins and the other with six T-shaped fins. Three-dimensional numerical models were created, considering the simulation of the melting process and accounting for time variations.