Exergy and energy analysis of sensible heat storage based double pass hybrid solar air heater

This research work discusses the exergy and energy analysis of an innovative double pass solar air heater with sensible heat storage. The system is evaluated in three different operating conditions; namely, natural convection mode, induced forced convection mode, and induced forced convection mode with a reflector. Performance analysis in all operating conditions evaluated and the best operating condition selected to apply crop drying and space heating application. Metco material and aluminum scrap mixture were used as sensible heat storage material below the bottom plate of the system. Experiments were conducted on three consecutive days for the different operating conditions. Average energy and exergy efficiency under natural convection mode is 11.47% and 2%, while 56% and 10.43% for a system operated under induced forced convection mode; however, 86.19% and 17.617% for a system operated under induced forced convection mode with a reflector. The third condition (system under induced forced convection mode with a reflector) has superior heat performance than the other two cases. Therefore, the proposed system is highly suitable for low-temperature applications.