Recent Advances and Perspectives of CFD–DEM Simulation in Fluidized Bed

The coupling of computational fluid dynamics (CFD) and discrete element method (DEM) has become an important method for studying dense fluidized beds. Since DEM can track the motion behavior of each particle individually and CFD can qualitatively and quantitatively describe the fluid evolution process, the discussion of fluidized beds using CFD–DEM method has been realized from small scale to laboratory scale and even extended to large engineering scale. This work presents a comprehensive review of the application of coupled CFD–DEM methods in fluidized beds and identifies the issues that need to be addressed. The detailed analysis is summarized mainly from the definition of particle flow system, DEM modeling theory (particle–fluid interaction and integration scheme of particle motion information, etc.), CFD modeling theory (discussion of turbulence model) and CFD–DEM coupled mapping methods (including Unresolved CFD–DEM and Resolved CFD–DEM). Existing studies have verified from multi-scales that the coupled CFD–DEM approach is reliable for predicting particle motion in fluidized beds. The findings are summarized and discussed, and future developments and challenges are highlighted. This work will provide theoretical guidance for subsequent researchers using the coupled CFD–DEM method.