Optimizing the geometric parameters of double branched fins for improving the melting performance of PCM

The escalating global energy demand necessitates advancements in energy storage technologies. Phase change energy storage technology is gaining momentum due to its sustainability, with the optimization of fin structural parameters being pivotal for enhancing the thermal performance of phase change materials (PCMs). This study introduces a novel three-tube heat exchanger design that employs molten salt as the PCM. The exchanger is divided into three distinct regions-PCM-HTF-PCM, with the aim of maximizing heat transfer efficiency between the heat transfer fluid (HTF) and the PCM. By varying the crossing angle (alpha) and the branch fin ratio (l*), the study investigates the influence of these geometric parameters on the system's heat transfer performance. The preliminary findings indicate that an angle close to 90 degrees and a smaller branch fin ratio can enhance melting performance. Utilizing existing simulation data, the Particle Swarm Optimization (PSO) algorithm is applied to optimize the branch fin's geometric parameters further. The outcomes reveal that the optimal geometric parameters are l* = 0.245 and alpha = 95.136 degrees, resulting in a predicted melting time of 1575.4 s and the 27.9 % enhancement in PCM heat transfer efficiency. Simulation experiments confirm that the actual melting time has a relative deviation /3 of only 1.38 % from the predicted value, thus validating the precision of the optimized design.