Particle-tracking studies for solids motion in a gas fluidized bed

The mean velocity distributions of solids, ranging from 0.42 and 0.8 mm, fluidized by air flows, ranging from 1.65 to 4.6 times the minimum fluidizing velocity, are presented. It is found that the patterns of gross solids circulation are heavily dependent on the fluidizing velocity and particles size. Sample measurements of limited range of conditions were obtained for a bed with a distributor plate smaller than the bed cross section and for a bed with a spherical internal structure. In addition, several exploratory studies were also conducted. Sample results of the Lagrangian auto-correlation and turbulent shear stress of the fluctuating velocities are presented. Furthermore, by superimposing selected sets of the tracer's location data to 'synthesize' the stratified bed experiments, a picture of the solids mixing was obtained. The results suggest that they are feasible and could be valuable in furthering the understanding of fluidized bed dynamics.