Performance analysis of solar air heater with porous obstacles

Solar air collectors have been used for drying process and space heating. The researchers made different designs on absorbing surface of these collectors to enhance the heat transfer. In this study, thermal performance analysis has been performed for five different types of solar air collectors.Closed-cell aluminum foams with 6 and 10 mm thicknesses and 50 cm2 surface area is placed on absorber plate increase heat transfer. Aluminum foams are placed on plate as staggered and non-staggered manner and experiments were done for flat collector in same conditions. Experiments are performed for June and July at different flowrates as 0.016 kg/s and 0.025 kg/s.Analysis was performed according to first and second law of thermodynamics and energy and exergy efficiencies are obtained. Totally, 16 parameters were tested. It is found that the collector designed by 6 mm staggered aluminum foam gives best result for all flow rates. Results are compared with literature and good results are obtained for energy and exergy efficiencies.