Performance comparison of latent heat thermal energy storage in duplex concentric finned tube with different HTF inlets

The latent heat thermal energy storage (LHTES) systems, that uses phase change materials (PCMs), has taken attention of researchers because of their higher energy density and almost isothermal storage. However, the low thermal conductivity of most PCMs makes it necessary to develop effective techniques to improve the heat transfer. To overcome this disadvantage, several techniques have been proposed to improve the heat transfer of LHTES. In this sense, the performance of the proposed system, duplex concentric tube with annular fins, is investigated using a 2D axisymmetric model with Comsol Multiphysics software, considering charging and discharging processes. The main objective of this work is to provide the optimal heat transfer fluid (HTF) injection scenario of the studied system for charging and discharging processes. As a results, the top HTF injection scenario can reduce the melting and solidification time by 10.66% and 15% respectively compared to the bottom HTF injection one. Therefore, the top HTF injection scenario is more performed and recommended.