Performance analysis of a serrated absorber plate solar air heater with paraffin wax storage

The study aims to examine the thermal performance of solar air heaters employing two different absorber plates under two different configurations. The experiments have been conducted in the summer climatic conditions of Moradabad City, India. A total of about 04 models of solar air heaters have been developed. The experimental investigation has been done using a flat-plate absorber and a serrated geometric absorber (with and without using the tested phase change material) to estimate the thermal performance. Notably, 03 different mass flow rates (i.e., 0.01 kg/s, 0.02 kg/s, and 0.03 kg/s) have been used to investigate the heat transfer coefficient, instantaneous efficiency, and daily efficiencies. Results of the study showed that Model-4 is the best among all the tested models that provide an average exhaust temperature of about 46 °C after sunset. The optimum daily average efficiency has been obtained at about 63% at 0.03 kg/s. The efficiency of a serrated plate-type SAH without using phase change material is about 23% higher than that of a conventional system, while it is about 19% higher than that of a conventional SAH using phase change material. Overall, the modified system is suitable for moderate-temperature applications, like agricultural drying and space heating.