Multi-field coupling and collaborative optimization design of the solar thermochemical cycle process based on ceria

Abstract

Most solar reactors commonly encounter challenges such as high-temperature gradients, suboptimal photo-thermal efficiency, and limited catalyst utilization. This lack of coordination in the design of solar reactors stems from the inadequate integration of the photothermal-chemical coupling synergistic relationship within the reactor. We developed a comprehensive multi-physics coupling mathematical model that incorporates optics, heat transfer, and chemical reactions to facilitate the cooperative optimization design of solar reactors. This study unveils the multi-field coordination mechanism within solar reactors. The optimization design of the secondary concentrator, reactor structure, fluid flow layout, and porous media catalyst structure was systematically carried out. A two-step thermochemical cycle of methane reducing cerium oxide decomposing water vapor to produce hydrogen was used as the reaction system to analyze the performance of the prototype reactor. The influences of ray power, reaction flow rate, and oxygen carrier mass on the solar-to-chemical efficiency were analyzed. The optimization results demonstrate that, by considering factors such as light power, mass transfer flow, and oxygen carrier mass within the optimization framework, the solar chemical energy conversion efficiency can reach a maximum of 38.75%.