Determination of the physical and interaction properties of sorghum grains:Application to computational fluid dynamics-discrete element method simulations of the fluid dynamics of a conical spouted bed

Computational simulation is an important tool for design and improvement of industrial units.Computational fluid dynamics(CFD)coupled with the discrete element method(DEM)has been applied to simulate drying equipment that usually involves gas-solid flow.For reliable results of CFD-DEM simulations,the properties related to the interactions of the material within the industrial equipment,such as the restitution or friction coefficients,must be known.In this study,CFD-DEM was applied to simulate the fluid dynamics inside a conical spouted bed operating with sorghum grains.The physical properties of the particulate phase and the particle-particle and particle-wall interaction parameters were determined by the direct measurement approach and applied to CFD-DEM.The interaction parameters were experimentally determined,including the particle-particle interaction parameters ofη=0.46,μ^(S)=0.79,andμ_(R)=0.70,and the particle-wall interaction parameters ofη=0.56,μ_(S)=0.75,andμ_(R)=0.40.The simulated minimum spouting velocity and characteristic curves were compared with the experimental results.There was good agreement between the simulated and experimental results.