Exergy Analysis of Photo-Thermal Interaction Process between Solar Radiation Energy and Solar Receiver

Abstract

A unified theory of non-equilibrium radiation thermodynamics is always in search as it is meaningful for solar energy utilization. An exergy analysis of photo-thermal interaction process between the solar radiation energy and solar receiver is conducted in this paper. The non-equilibrium radiation thermodynamic system is described. The thermodynamic process of photo-thermal interaction between the solar radiation and solar receiver is introduced. Energy, exergy and entropy equations for the photo-thermal process are provided. Formulas for calculating the optimum receiving temperatures of the solar receiver under both non-concentration and solar concentration conditions are presented. A simple solar receiver is chosen as the calculation example to launch the exergy analysis under non-concentration condition. Furthermore, the effect analysis of solar concentration on the thermodynamic performance of the solar receiver for solar thermal utilization is carried out. The analysis results demonstrate that both the output exergy flux and efficiency of the solar receiver can be improved by increasing the solar concentration ratio during the solar thermal utilization process. The formulas and results provided in this paper may be used as a theoretical reference for the further studies of non-equilibrium radiation thermodynamic theory and solar thermal utilization.