Study of Heat Flux Density of Dish Solar Cavity Heat Absorber

Abstract

The solar cavity heat absorber is the core component of a solar thermal power generation system; its structure and installation position directly affect the efficiency of the heat absorber. To study the influence of these factors on the performance of the heat absorber, in this paper, a numerical simulation of dish solar collector optics is constructed based on the Monte Carlo method, and the distribution characteristics of heat flux density under different heat absorber structures and installation positions are analyzed. The results show that the heat flux density on the inner wall surface of the absorber has a linear relationship with the solar radiation intensity; under the same cavity depth, the energy received by the cylindrical, dome, and inverted cone absorbers is easier to deposit on the top. The heat flux density on the top surface of the inner cavity presents an annular distribution law. As the position of the heat absorber moves away from the dish solar collector surface, the top energy is gradually transferred to the circumferential surface. When the heat absorber is in position B, the total power ratio of different heat absorber structures entering the cavity can reach 99%. At this time, the circular type of heat absorber is more conducive to the full heat absorption of the working medium.