Numerical analysis and optimization of a fin system for the thermal control of a Compound Solar Receiver (CPC)

Abstract

The work presented consists of studying the flow of a fluid in a Composite Parabolic Concentrator (CPC) coupled with a solar receiver at the head of a solar power plant in a laminar and turbulent regime under the effect of the heat transfer phenomenon: natural convection, conduction and radiation. In our study, we have a CPC in the form of a truncated cone and circular fins of trapezoidal shape, it is coupled by a solar receiver composed of two glued truncated cones. The number of fins is set to be (one, three, seven and thirteen). This work aims to find solutions to reduce the wall temperatures of CPC (Aluminum) to avoid deterioration of its material. This study led us to propose fin configurations whose choice was to choose the case that gives the lowest wall temperature and that it does not affect the configuration of the CPC so as to avoid the congestion of fins on the wall and also the influence on the temperature of working fluid (heat transfer fluid) inside the solar receiver. The flow of air inside is permanent three-dimensional and viscous, the process is non-adiabatic, the system is subjected to solar radiation, heat exchange is carried out according to the laws of conservation. To have a better approach on the thermal behavior and a flowing fluid in the compound system and to make the study in three dimensions, one resorted to the software of simulation "FLUENT" which proved itself in the dynamics of the fluids and heat transfers, this simulation allowed us to determine the thermal parameters especially the parietal temperature and the characteristics of the flow. After our studies, we chose the case 7 fins as the best case for the cooling of the CPC wall. Finally, the results obtained are very satisfactory comparing our study with other works. We also studied the influence of some parameter such as CPC wall thickness, Reynolds number, Quartz lens and angle of inclination α.