CFD-DEM simulation of single jet fluidized bed using scaling methods

CFD coupled with DEM is a powerful tool for analyzing dense gas-solid flows. However, the computational expenditure associated with CFD-DEM renders it unfeasible for modeling large-scale engineering applications involving billions of particles. A combined CFD-DEM approach, henceforth referred to as the scaling method, is proposed, integrating model reduction with coarse-graining of particles to diminish computational volume by various means. The particle count experiences an order-of-magnitude decrease by aggregating multiple primitive particles into a single computational unit according to the coarse-grain ratio; in terms of modeling, the mesh quantity diminishes by scaling down the model based on the flow-field similarity criterion, thereby further decreasing computation time.The first step in determining whether or not the numerical simulation was accurate was to use high-speed photography. Subsequently, we used the CFD-DEM with the scaling methods to analyze the transient spatial distribution, the transient mean velocity in the vertical direction, the pressure drop, and the bed height of the single Jet Fluidized Bed. Next, we compared the CFD-DEM of the scaling methods with the original CFD-DEM results. The comparison showed excellent agreement between the two sets of results, indicating the accuracy and practicality of the method. The computational time of the CFD-DEM scaling methods is assessed, revealing a considerable reduction in computational time with an increase in the particle coarseness ratio and the model reduction ratio. This paper offers a theoretical framework for the numerical modeling of CFD-DEM utilizing the scaling methods in dense gas-solid flow. • The applicability of the CFD-DEM scaling method in the simulation of Single Jet Fluidized Bed is discussed. • The CFD-DEM scaling method is able to simulate the jetting phenomenon in a Single Jet Fluidized Bed. • The uncertainty of the CFD-DEM scaling method increases with the degree of coarsening and reducing.