Discrete element method simulation of three-dimensional conical-base spouted beds

A discrete element method (DEM) simulation of three-dimensional conical-base spouted beds is presented. The overall height and diameter of the vessel are 0.5 and 0.15 m, respectively, and the nozzle diameter is 0.02 m. The inclined angle of the conical section varies from 0 to 60 degrees. The gas flow is described by the continuity and Navier–Stokes equations and solved by a finite difference method of second order accuracy in space and time. For gas–particle interaction, the Ergun equation (for void fraction smaller than 0.8) and the Wen-Yu model (for void fraction of 0.8 and above) are employed. A new method for treatment of the boundary condition for 3-D gas flow along the cone surface is proposed. This boundary condition satisfies both the continuity and momentum-balance requirements for the gas phase. Usefulness of the present simulation for studying gas flow pattern and particle motion in conical-base spouted beds is demonstrated. The effects of the inclined angle and draft tube on gas and particle flow in spouted beds are discussed.

Graphical AbstractDiscrete element method simulation of conical-bottomed spouted beds is performed by incorporating an embedded boundary treatment for gas flow along the cone surface. The results are compared with measurements reported in the literature and also with simulation results of flat-base spouted beds. The characteristic spouted bed behaviours such as spout, annulus and fountain formation are reproduced in our DEM simulations.Figure optionsDownload as PowerPoint slide