An Evaluation of the Effects of Surface Coating on the Performance of Flat Plate Solar Collectors

Abstract

The objective of the present work is to investigate the effect of paint coating on the efficiency of the flat plate collector. In this study two types of the collector were been designed: Type (A) uncoated and type (B) paint coated collectors and type (C) coated with Rhoddonite (Mn-SiO3). The inlet and outlet water temperatures where compared together with the rise in temperature and its change in the collector and so the rise and fall of solar radiation up on the collector. Also measured the rise in temperature of type (C).Temperature was recorded every half hour during the day (9:00am, 6:30pm).It was noticed that the collector outlet temperature changing with the solar radiation change during the day where the outlet temperature increases with the radiation and vise versa. Maximum outlet temperature of type (A) collector was found to be at 917w/ m2 where as that of type (B) was at 926 w/ m2 and hence it could be said that the paint coating increased the efficiency of the collector .The distance between the tubes was set to be 10 cm in both types. It was found that it is possible to raise the efficiency of the collector by improvise properties of the materials used in the design special high absorbativity to infrared radiation and decreased reflectivity via studying surfaces which may improve efficiency of the collector