As the global energy demand is increasing [1], storing energy is found to be one of the major challenges of today's era. Thermal energy storage (TES) is considered to be very significant among the various forms of energy storage, because of its ability to store and releasing energy in the form of cold or heat [2]. Among the different TES forms, latent heat thermal energy storage (LHTES) is found to be highly effective as it stores high energy amount at a nearly constant temperature when phase change occurs [3]. This ability of LHTES makes it applicable to solar energy systems using phase change materials (PCMs).
The intermittency associated with solar energy is a major restriction for its continuous usage, which can be dealt with using TES. The surplus solar energy can be converted into thermal energy and stored in a PCM, and discharged whenever the energy demand occurs. The application of PCM in a flat plate collector is focused in this present study. In this study, a numerical simulation is done for a solar water heater (SWH) with a shell-and-tube PCM storage unit by using the CFD tool ANSYS.