The reformation of methane to hydrogen and steam in a falling particle solar reactor (FPSR) is a promising method to use the solar energy, which converts solar energy into chemical energy. FPSR has higher operation temperature, higher pressure bearing capacity and more direct heat energy storage than those of traditional reactor. However, due to the short residence time of the particles, hydrogen production efficiency is reduced. Thus, inlet arrangement strategies and particle catalysts should be carefully designed to improve the thermochemical reaction performance of FPSR. In this contribution, the Eulerian-Eulerian model in CFD program (Fluent 2020 R2) is used to explore the effects of different particle inlet arrangement strategies, non-uniform particle mass flow inlet and particle size on the performance enhancement of methane steam reforming reaction. The results indicate that the two arrangement strategies show different trends in influencing hydrogen production efficiency. Besides, non-uniform particle mass flow rate also has a significant impact on hydrogen production efficiency, with the optimal arrangement conditions increasing the hydrogen production rate by 2.4831 mol/m−3(−|-) s−1. Additionally, smaller particle size demonstrates better hydrogen production efficiency, with a 0.15 mm particle size catalyst showing a 14.02 % improvement in hydrogen production efficiency compared to a 0.75 mm particle size. This contribution can provide a guidance for optimizing the heat and mass transfer performance of the falling particle solar reactor.
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