Investigation and Improvement of Thermal Performance of a Solar Air Heater Using Extended Surfaces Through the Phase Change Material

Abstract

Abstract Low thermal conductivity is the main drawback of using paraffin wax as a latent heat thermal storage material in the solar air heater (SAH). In order to overcome this drawback, an absorber plate with extended surfaces through the paraffin wax was used. Two extended surface absorbers were used: a flat plate attached with downward fins and a V-corrugated plate. For the purpose of comparison, the SAH integrated with paraffin wax was tested using three proposed types of the absorber plate: flat, downward finned, and V-corrugated plates. The results showed superiority of the downward finned plate during the day. But the V-corrugated SAH remains the best choice for the applications in which the hot air is mostly needed during night as it is continuously operated for 7 h after sunset with the outlet air temperature of 8–11 °C more than the ambient air temperature.