Enhancing PCM melting performance through modified fin designs in latent heat thermal storage systems

This numerical study investigates the influence of fin geometry on the melting behavior of PCM (high-density polyethylene, HDPE) within a shell-and-tube latent heat thermal energy storage (LHTES) unit. The enthalpy-porosity method was utilized to model the solid-liquid phrase change process dominated by heat diffusion. A novel tree-shaped fin design is introduced and compared with conventional fin geometries, including rectangular, Y-shaped, and V-shaped fins, to enhance the PCM melting performance. Five heat exchanger configurations, with and without fins, were analyzed to assess their thermal efficiency. Four of these units were fitted with eight fins each, with all fins in a given exchanger sharing the same shape. The results demonstrate that the tree-shaped fins achieve the greatest reduction in total melting time, with a decrease of 75.7 %, compared to 52.56 % for the Y-shaped fins and 54.6 % for the V-shaped fins relative to rectangular fins.