Closed Solar Air Heater System Integrated with PCM (RT42 and RT50) in a Thermal Storage-Finned Heat Exchanger Unit

Abstract

Utilizing thermal storage integrated into a solar air heater SAH is a promising solution to enhance the thermal performance of solar air heaters. The present work experimentally investigated the thermal impact of an absorber-finned heat exchanger-thermal storage unit integrated inside a solar air heater. The experiments were conducted under the conditions of Tikrit-Iraq in December 2021 and January 2022. RT42 and RT50 were used as PCMs in two separate solar air heaters. Each PCM filled the thermal storage of SAH. A finned heat exchanger, in which air was forced through, was immersed in the thermal storage. Two arrangements were tested. In the first arrangement, the two SAHs were separated from each other. In the second arrangement, the two SAHs were connected in series, first the RT42 SAH and then the RT50 SAH. The results showed that the highest recorded temperature was for RT50, i.e., 59 °C, in the separation arrangement. Also, the solar air heater with RT50 in the series arrangement continued to heat the forced air until 5 AM the next day.