Experimental analysis of latent thermal energy storage charging and discharging

Experimental investigation of latent thermal energy storage (LTES) charging and discharging has been performed. The LTES unit is a shell-and tube type tank with water as the heat transfer fluid (HTF), which flows through the tubes, and technical grade paraffin RT 25 as the phase change material (PCM), filling the shell side. The total of 19 longitudinally finned tubes are arranged concentrically in the tank. A set of 30 thermocouples have been placed at various radial and axial positions on the PCM side for monitoring transient temperature variations during charging and discharging processes. Timewise temperature variations of PCM during charging and discharging, for different HTF inlet temperatures, have been presented. Stored and released thermal energy have been calculated and analyzed.