Numerical investigation of latent heat thermal energy storage system

Abstract The present work aims to study numerically the performance of a latent heat thermal energy storage unit. Which is composed of shell and tube. The annular space is filled by a phase change material (PCM), however the water used as a heat transfer fluid (HTF) flows in the inner tube. The computational are based on an iterative numerical procedure that incorporates an enthalpy formulation for the modeling of the solid-liquid phase change. Then our numerical model was validated with experimental and numerical results of the literature, where a good agreement was obtained. A series of numerical computations was conducted to study the effect of different flow parameters: the inlet temperature (88°C, 75°C and 65°C) and the mass flow rate (0.072, 0.8 and 0.1 kg/mn) of HTF on the thermal energy storage. The obtained results shows that the variation of the inlet HTF temperature has a great effect on the thermal performance of the storage unit, relative to the variation of the mass flow in terms of the operating time of the storage (charging and discharging) and the outlet temperature of the heat transfer fluid