Discrete Particle Simulation and Visualized Research of the Gas−Solid Flow in an Internally Circulating Fluidized Bed

Dispersion characteristics of dissimilar materials in a fluidized bed with unevenly distributed fluidizing air

“…Through visualization experiments, Bin et al [14] confirmed that there is a transverse movement of bubbles from the high-velocity side to the low-velocity side in internally circulating fluidized beds. Wei et al [15] developed a particle image technique to analyze the dispersion of tracer particles (with similar properties to the bed materials) in an ICFB.…”

“…The circulation was controlled by producing an imbalance in the air supplies to different zones of the distributor, tilting the distributor (so that the flow is up the slope), or the use of a spout as a pump. The three methods mentioned above have been employed as the main ways to induce an internal circulating flow in fluidized beds [3][4][5][6][7][10][11][12][13][14][15][16]. Thus, this fluidized bed is called an ICFB.…”

“…The image technique has also recently been widely applied to achieve comprehensive two-dimensional visualization in fluidized beds in recent years [5,14,15,27,[31][32][33]. Through visualization experiments, Bin et al [14] confirmed that there is a transverse movement of bubbles from the high-velocity side to the low-velocity side in internally circulating fluidized beds.…”

“…Thus far, there have been many publications about the characteristics of the particle movement in an ICFB [14,15,24,34]. Nevertheless, there has been little research on the lateral mixing of particles in an ICFB, especially for dissimilar materials.…”

Discrete element study of solid circulating and resident behaviors in an internally circulating fluidized bed

“…Greek symbols b gs inter-phase momentum transfer coefficient, kg/(m 3 s) d n,ij normal displacements between particle i and particle j, m d t,ij tangential displacements between particle i and particle j, m D sub-grid characteristic length scale, m Dx, Dy, Dz mesh size in the x, y and z dimensions, m [24] studied the gas-solid flow in an ICFB with the combination of computational fluid dynamics coupled the discrete element method (CFD-DEM). They found that the particle circulation from the high-velocity region to the low-velocity region is established with uneven air distributions.…”