Experimental Thermal Performance of Phase Change Material Embedded Solar Air Heater Employing Impinging Stable Air Jet Array Presenting High Power and Energy Density

Abstract

Abstract This experimental thermal performance investigation presents that the hot air at a significantly high temperature, and simultaneously at high power density and energy density of phase change material (PCM) can be obtained utilizing a novel design of PCM embedded solar air heater employing impinging stable air jet array. Investigation is carried out following two main objectives, i.e., to obtain (i) instant and (ii) long thermal backups. In the reported design configuration, impinging stable air jets on absorber plate are obtained by reducing the flow path of expelled air from upstream air jets that increased the heat transfer rate to air and consequently instant thermal backup. Although, the use of wavy PCM unit provides instant and long thermal backup by increasing heat transfer area that augments the heat transfer to air and the collection of solar radiations, respectively. Moreover, the present study is extended as follows, (i) the use of shutter on glass cover to increase thermal performance during nocturnal hours, (ii) charging of PCM till the maximum solar radiation hours and use of the stored energy during nocturnal hours, (iii) thermal performance analysis to reveal instant thermal backup, (iv) thermal performance investigation during variable weather conditions, and (v) thermal performance investigation for low ambient air temperature. The obtained results revealed that for the unit collector area, significant thermal backup of about 6 h at a temperature rise of ≥5 °C can be obtained by utilizing the above-mentioned provisions in this research.