Experimental investigations on the thermal efficiency of a solar air collector with transverse rectangular baffles incline by an angle of 135°

Abstract

This work is experimental investigation on the impact of rectangular baffles on the thermo-hydraulic performance of a solar thermal collector. The study was conducted under moderate weather conditions and six cases were studied, including 2M135, 6M135, 10M135, 14M135, 18M135, and a smooth plate case. The results showed that the number and placement of baffles plays a crucial role in improving heat transfer and the best cases in terms of thermal performance were cases V and IV, with maximum values of h = 15.84 W/m2.k, and h = 17.46 W/m2k. The study also found that the heat transfer was greatest at the beginning of the channel and decreased towards the end. The highest thermal efficiency was recorded in case 18M135 with a maximum value of Ƞ=0.73.

Keywords

• Baffles
• Heat transfer
• Nusselt number
• Solar thermal collector
• Thermo-hydraulic performance