Temperature Difference with Respect to Exposure Time for Black Paint and Galena Powder-Black Paint Composite Selective Surfaces

摘要

In solar water heating systems for domestic use, flat-plate solar collectors can be successfully employed and normally installed facing south on a rooftop at an angle of about 40°. Tracking system in configuration with the collectors is very useful for reaching high temperature in a moderate weather, while this combination is not necessary in hot weather zones. Practical and theoretical details about history of solar energy, collectors, and applications of solar energy have been reported by Kalogirou (2004). The intensity of solar radiation that strikes the Earth at the surface of the Earth's atmosphere is around 1.36 kW/m~2 (Al-Waeli et al. 2015). This source of energy can be exploited in many ways for very long time. Very important details about using of materials for heating system by solar energy have been almost fully reported by Lenel et al. (1984). Chatterjee and Pal have announced that thin film of Galena can be used as low-cost selective absorber (Chatterjee and Pal 1993). Large-scale applications of hot water system in Europe have been reviewed by Fisch et al. (1998).