Thermal Performance Improvement Study of a Solar Collector with Compound Parabolic Concentrator

Abstract

Heating water with solar energy is easy and effective in both domestic and industrial areas. The initial implementation cost of a solar-water-heating system is high but long term use of it makes it cost effective. For geographical location, Bangladesh is very suitable for using it. In a solar collector system, collector area is an important design factor. To achieve better thermal performance, 0.81m2 solar collector was used in this study. Commonly used flat plate collector takes more space to be installed. In Bangladesh, space on the roofs of houses and industries are limited and so there is a little scope to use flat plate collector system. Compound parabolic collector can solve this problem. Solar collector with compound parabolic collector needs less space than flat plate collector with reflector. When compound parabolic concentrator was attached with the solar collector, thermal performance improves. Compare with other alternatives that improve thermal efficiency, compound parabolic concentrator shows better thermal performance. Compare thermal efficiency of the consecutive three months. In this system, when water flow rate increase, outlet water temperature decrease but thermal efficiency increases. It is also observed that when solar intensity increases, thermal efficiency also increases likewise when solar intensity decreases, thermal efficiency also decreases. In this research, outputs of different similar researches are compared to show the effectiveness of the compound parabolic concentrator based solar collector. The compound parabolic concentrator reflects more solar radiation, eventually directs it to the collector and increased the difference between the inlet and outlet water temperature.