Performance Enhancement of Shell and Tube Latent Thermal Storage System Using Copper Foam

Abstract

Latent Heat Thermal Storage (LHTS) based on Phase Change materials (PCMs) offers a promising solution for efficient utilization of intermittent energy from renewable sources. The primary limitation is the poor thermal conductivity of PCMs, which requires employing of thermal performance enhancement techniques. To enhance the thermal performance of PCM thermal energy storage, a copper foam with a high porosity is embedded with the PCM. A numerical simulation model has been developed to investigate the thermal behavior of two LHTS shell and tube configurations: pure PCM-LHTS (conventional LHTS) and PCM - copper-foam composite (foamed LHTS). The effect of the heat transfer fluid (HTF) temperature on the thermal response of LHTS during the charging process was considered. The results showed that the length of melting time for foamed LHTS was shorten about 82% as compared to conventional LHTS under the conditions of HTF temperature of 70°C and flow rate of 0.083 kg/sec. The results show that when the initial temperature of HTF for LHTS with foam was changed from 70°C to 75°C and then from 75°C to 80°C, the total charging time was enhanced by about 33 % and 29%, respectively. Based on results of temperature variation and liquid fraction of PCM, employing copper foam improved the charged thermal load during the charging process compared to LHTS without foam.