Abstract: [Objectives] In recent years, the integration of thermochemistry and concentrating solar power technologies has led to novel applications for solar thermal technologies. However, the coupling between thermochemical reactors and solar concentrators such as solar furnaces remains insufficient. Therefore, it is necessary to study the energy flux density on the receiving surface of thermochemical reactors and propose an optimized design method for concentrators specifically for receiving surface. [Methods] Taking a solar furnace with tilted receiving surface as the research object, a numerical simulation model using the ray-tracing method is established to explore how design variations of receiving surface of reactors affect the energy flux density distribution at the target surface. The effect of ray incident angles at the target surface on the concentrating contribution of solar furnace concentrators is analyzed and used as a constraint to optimize the design of concentrators. Additionally, the performance of optimized concentrators is analyzed. [Results] The edge region of the concentrator causes significant distortion of the focal spot and a notable decrease in energy flux density contribution. By constraining the incident angle of concentrated rays at the target surface, the peak energy flux density of the focal spot can be increased by 18.52% and the power at the target surface improved by 6.53%, while maintaining the same mirror area [Conclusions] This study provides the influencing pattern of energy flux density distribution for the design of thermochemical reactor receiving surface and proposes a method for optimizing concentrator design tailored to reactor receiving surface. The findings contribute significantly to the coupling and matching of solar thermochemical systems.

Key words: thermochemistry, solar energy, energy storage, solar thermal, solar furnace, numerical simulation, concentrator, energy flux density distribution