Development of a novel two-stage parabolic dish collector-receiver system for efficiency improvement

Abstract

ABSTRACT This paper is related to the solar radiation concentrating at two focus points, at which three stages of receivers are located. It refers to the improvement of the thermal collection efficiency of the parabolic dish concentrator (PDC) system by using a twin-staged concentrator and three-staged receiver system. It discloses system design that concentrates the incident solar energy in varying proportions subsequently at low-, medium-, and high-temperature solar cavity receiver stages. It is seen that the modified design demonstrated increased thermal collection efficiency as compared to the conventional single-stage system. It improved the system efficiency by about 12.4% for lesser flow Reynolds number (Re). For the entire studied flow range, the average percentage increase in system thermal efficiency is about 8.6%. The twin-stage system demonstrated insignificant improvement in the flow transition zone. In the case of a developed system, the percentage contributions of losses by conduction, convection, and radiation are varying from 1.5–2.7%, 59–62%, and 36–37%, respectively.