Abstract
Energy storage and recovery are of prime importance in thermal energy storage design. To evaluate this phenomenon in phase change materials (PCM) thermal energy storages, a square channel with multiple tubes connected in serial arrangement has been experimentally analyzed for different tilt angles. PCM type RUBITHERM (RT-42) acts as a thermal energy storage medium, and the whole setup is designed in two configurations, i-e, only PCM and PCM with aluminum metal foam. The setup comprises a thermal bath, distilled water, circulation pump, data acquisition system, thermocouples, flow regulating valves and thermal storages under investigation. The study reveals that, the presence of metal foam along with PCM results in an enhanced heat transfer rate (up to 3∼4 times) compared to only PCM case due to the uniform distribution of temperature provided by highly conductive metal foam. The analysis of thermal storage at different tilts suggests that there is no significant improvement in heat transfer rate in PCM embedded metal foam cases with inclination due to enhanced thermal conductivity and uniform temperature distribution. However, for the full PCM case, the heat transfer rate in thermal energy storage is increased up to ∼1.6 times with the increase in inclination due to the presence of buoyancy force.