太阳能直接辐照下碳酸钙颗粒的粗颗粒CFD-DEM 模拟

The thermochemical energy storage based on Calcium carbonate (CaCO₃) shows great potential for the next generation of high temperature solar thermal power station due to its non-toxicity, high energy storage density, and good compatibility with supercritical CO₂ thermal cycle. However, conventional thermochemical heat storage technology is based on indirect surface-heating, which suffers high heat loss and low efficiency. Therefore, we propose a fluidized particle reactor under direct solar irradiation. A Computational Fluid Dynamics-Discrete Element Method (CFD-DEM) and coarse-grained method (CGPM) coupled with the Monte Carlo method (MCRT) are built to simulate the energy storage process. The results show that the temperature rise and reaction time of CACO₃ particles can be predicted by the two models, which are in good agreement with the traditional CFD-DEM results. In addition, with the increase of the packing coefficient, the CGPM model shows good computational performance, and the computational time is significantly shorter than that of CFD-DEM model. The established CGPM-MCRT model has important guiding significance for the design of large-scale and efficient direct irradiation thermochemical heat storage system. The temperature rising and reaction time can be predicted, and the results of CGPM are in good agreement with those of traditional CFD-DEM. In addition, with the increase of the packing coefficient, the computational time of CGPM is significantly shorter than that of CFD-DEM model. The established CGPM-MCRT model will guide the design of efficient direct solar-driven thermochemical heat storage system.