Single pass solar air heater with transverse fins and without absorber plate

Abstract

Paper presented at the 9th International Conference on Heat Transfer, Fluid Mechanics and Thermodynamics, Malta, 16-18 July, 2012.

The single pass solar air heater, with transverse fins and wire mesh used as an absorber plate, is constructed and tested for thermal efficiency at a geographic location of Cyprus in the city of Famagusta. The absorber plate was replaced by sixteen steel wire mesh layers, 0.18 x 0.18cm in cross section opening and a 0.02cm in diameter. The fins were painted with black color and positioned transversely along the bed such that four equally spaced sections were created. The transversely fins are arranged in a way to force the air to flow through the bed like eight letter path. The obtained results show that for air mass flow rate rang between 0.011-0.032 kg/s, the thermal efficiency increases with increasing the air mass flow. The maximum efficiency obtained is 58% for the mass flow rate of 0.037 kg/s. Moreover, the temperature difference between the outlet flow and the ambient, ΔT, reduces as the air mass flow rate increases. The maximum difference between the outlet and ambient temperature obtained was 40.6 oC for mass flow rate of 0.011kg/s. Comparison with a conventional single pass collector shows a substantially enhancement in the thermal efficiency.