Performance Study of Solar Air Heater with Baffled Duct

Abstract

The paper presents results of an experimental performance study of a solar air heater having perforated baffles (baffles open area ratio of 46.8%) on the air flow side of the absorber plate. A direct performance comparison of the baffled duct and smooth duct solar air heaters shows that the thermal efficiency of the baffled duct solar air heater is about 22-33% higher than the smooth duct solar air heater; highest thermal performance advantage is at the lowest flow rate. The enhancement is attributed to the heat transfer enhancement due to the perforated baffles on the absorber plate and reduction in the mean absorber plate temperature. The pumping power requirement has been found to be only a small fraction of the heat collection rate. Key