Leaf-vein bionic fin configurations for enhanced thermal energy storage performance of phase change materials in smart heating and cooling systems

In the present study, we investigated the effect of different structures of a novel leaf vein bionic fin and various arrangements in the tube on the complete melting time of phase change materials (PCM) in a triplex-tube thermal energy storage (TES) system. RT82 was adopted as the phase change material. The enthalpy-porosity method was employed for this numerical study. The numerical model was validated against experimental data from a previous reference. The simulation results demonstrate that the novel fins deliver significant reductions in the duration of complete melting. Based on fin-branched vein numbers of 1, 2 and 3, increasing the fin angle from 30 degrees to 60 degrees can reduce the complete melting time by up to 14.3%. Additionally, adjusting the fin arrangement can save up to 6.35% of the complete melting time. The proper arrangement of the fins can improve the heat transfer performance of the PCM. The non-dimensional quantities analysis of the calculated results shows that the melting time is negatively correlated with the non-dimensional angle. As the non-dimensional parameter, fin arrangement number decreases from 1, the complete melting time corresponding to the fins of different structures first decreases and then increases for the phase change material.