Numerical investigation and optimization of an experimentally analyzed solar CPC.

Abstract In this study a compound parabolic collector (CPC) taken from literature was investigated optically and thermally through simulation. The collector was tested at different transversal and the longitudinal incident angles and the results showed us a total agreement between the present and the previous study where TracePro software was used. In addition, a new optical efficiency relationship was proposed and it was found that diverges significantly from the commonly used relationship as the reflector's shape losses and/or the absorber's diameter increase. Also, the CFD analysis results were validated from the previous study experimental data (4.2% mean divergence in thermal efficiency), something that reveals how sufficiently the real problem has been approached. Finally, an optimization process was followed in order to improve the collector's optical performance, while the novel CPC resulted from the optimization was compared with the initial design for the typical conditions of the 11th of June in Athens from 08:00 to 16:00, in order to examine the effect of different solar irradiation intensities in the comparison process. It was revealed that the novel design exceeds the initial one in all the examined hours. The design and the simulation of the collector were conducted via Solidworks Flow Simulation software. Highlights • A new optical efficiency relationship is proposed. • The previous ray tracing agree with the present one (2.9% and 1.8% mean deviations). • The simulation results diverge 4.2% on average from the experimental one. • The present simulation exceeds the previous theoretical solution in accuracy. • The novel design enhances the optical efficiency by 2.4% regarding a daily operation. [ABSTRACT FROM AUTHOR]