Experimental analysis of a phase change material (PCM) enhanced solar air heater for thermal energy storage

• Paraffin wax is an effective energy storage material for solar air heaters. • Heat storage is more influenced by solar intensity than mass flow rate. • Phase change materials contribute to improved performance in solar air heaters. Solar air heaters are widely used heat exchangers that transfer energy from the sun to the working fluid. However, their thermal performance decreases significantly in cloudy weather and at night due to the absence of real-time solar energy. In this experimental study, heat storage was aimed by using phase change material integrated into a storage unit with rectangular fins on the absorber surface. The absorber was made of copper material and commercial Paraffin Wax was used as the phase change material. The thermal energy storage capacities of solar air heaters with and without phase change material were compared under irradiance intensities of 800 W/m 2 and 1000 W/m 2 , and mass flow rates differing from 0.002 kg/s to 0.003 kg/s, using artificial radiation. As a result of the experiments, the highest heat storage amount of 477.4 kJ was obtained for the solar air heater using paraffin as phase change material in the storage unit, with a flow rate of 0.002 kg/s and an irradiance intensity of 1000 W/m 2 . The lowest heat storage amount of 11.7 kJ was obtained for the solar air heater with no paraffin in the storage unit, a flow rate of 0.003 kg/s, and an irradiance flux of 800 W/m 2 . The findings demonstrate that incorporating paraffin significantly enhances the system’s heat storage capability.