Thermal analysis of modified conical cavity receiver for a paraboloidal dish collector system

Abstract

ABSTRACT In a solar paraboloidal dish collector system, the receiver is critical for transforming converged solar flux to heat energy. A cavity receiver is the most common type of receiver, as it lowers heat loss. An experimental investigation is carried out in this article to evaluate the thermal performance of a novel cavity receiver for dish system under real direct solar environments. The performance of the modified conical cavity receiver under stagnation condition and with heat transfer fluid was studied experimentally. A solar parabolic dish concentrator of 1.83 m rim diameter and rim angle of 66° was used for the experimentation. For both cases, the experiments were carried out for two days. The highest stagnation temperature of 167.2°C was recorded with a direct irradiance of 803 W/m2, according to the data. For day average direct irradiance of 555 W/m2 and 663 W/m2, the receiver’s average thermal efficiency was found to be 53% and 69%, respectively. For 694 W/m2 direct irradiance, a maximum thermal efficiency of 75% was achieved. The thermal efficiency was shown to be significantly dependent on direct irradiation. According to the results of the experiments, the proposed modified conical cavity receiver is a viable solution for solar parabolic dish collector systems.