Experimental Study of A LTES Made By a Finned Heat Exchanger Immersed In a Paraffinic PCM

–In this paper, a new Latent Thermal Energy Storage (LTES) system, made by a finned tube heat exchanger immersed in the commercial paraffinic Phase Change Material (PCM) RT44HC is studied experimentally. The storage capacity and the thermal performance of the LTES during both melting and solidification processes of the PCM was analysed for different test conditions using water as heat transfer fluid. In particular, experimental tests were performed by considering several values of hot and cold water temperature at the heat exchanger inlet, ranging from 55 to 70 °C and from 14 to 29 °C during charging and discharging processes, respectively. For each test, three different values of the water flow rate through the heat exchanger (25, 50, 100 kg/h) were considered. Results show how the thermal power increases considerably by charging (discharging) the LTES with higher (lower) inlet water temperature and with a higher water mass flow rate. For a fixed inlet water temperature and for growing flow rates, an increase in thermal power up to 1.16 kW occurs. For fixed flow rates, a thermal power increase of 49.5% is registered going from 50 to 70°C of the inlet water temperature. The thermal performance of the LTES are also compared with those obtained using pure water as heat storage material, outlining that the storage capacity of the system using PCM instead of water is increased of about 300-400%.