Experimental investigation of thermal performance of solar air heater having different obstacles on absorber plates

This paper presents the results of an experimental investigation of the performance for a new flat plate solar air heater (SAH) with several obstacles (Type I, Type II, and Type III) and without obstacles (Type IV). The efficiencies, the heat gain factors and heat loss coefficients are determined for the collectors and comparisons were made among them. The experimental data along with the correlations obtained by linear regression are presented. The optimal value of efficiency was determined for the solar air heater with Type II absorbent plate in flow channel duct for all operating conditions and the collector supplied with obstacles appears significantly better than that without obstacles.