Effect of Bed Thickness on the Segregation Behavior of Particle Mixtures in a Gas Fluidized Bed

Discrete particle simulation has been recognized as a useful numerical technique to elucidate the fundamentals of particle−fluid flow, in particular, gas fluidization. In general, it is achieved by combining discrete element method (DEM) for solid flow with computational fluid dynamics (CFD) for continuum gas. Limited by computational capability, such studies are mainly conducted using a two-dimensional (2D) bed in which particles are treated as discs or a pseudo-three-dimensional (3D) bed where the bed thickness is the same as the particle diameter. The loss of one-dimensional motion may significantly affect the flow and related behavior. This paper presents a numerical study of the effect of the front and rear walls of a fluidized bed on the mixing and segregation behavior of particle mixtures. Particle diameters used for simulation are 1 mm for flotsam and 2 mm for jetsam, respectively. Numerical simulations are conducted for two beds of different thicknesses, fluidized at different gas velocities. One...

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