Numerical Simulation Study on Solar-Driven CeO₂ Reduction Reaction

The advancement of the economy, population, and science and technology has intensified energy and environmental pollution issues. The development of clean and renewable energy has become a major concern for the global community. One of the most promising methods for harnessing solar energy to produce clean energy is the two-step thermochemical decomposition of CO<inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</inf> or H<inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</inf>O. In the first reduction reaction of this method, the reaction temperature not only indicates the reactivity of CeO<inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</inf> but also impacts its reduction efficiency and heat exchange. On this basis, this paper establishes a model coupling free flow and porous media flow, a heat transfer model, and a physical model using COMSOL Multiphysics and integrates them to calculate their temperature distribution over time. The temperature changes of the reactor under the radiation intensity of $786.6 \mathrm{~kW} \cdot \mathrm{~m}^{-2}, 1179.9 \mathrm{~kW} \cdot \mathrm{~m}^{-2}$, and $1573.2 \mathrm{~kW} \cdot \mathrm{m}^{-2}$ at the aperture were obtained. It is concluded that a higher quantity of solar heat leads to higher temperatures in the model, with other conditions remaining constant.