Hydrodynamic Behavior of Particles in a 3D Integral Multi-Jet Spout-Fluidized Bed.

The hydrodynamic behavior of particles in a 3D integral multi-jet spout-fluidized bed has been studied experimentally by particle image velocimetry method. In the cross section of the spouted bed, especially in the annulus, it was found that particle movement can be effectively promoted by adding the integral multi-jet, thus enhancing the radial movement of particles in the annulus and effectively eliminating the dead zone of particle flow in the annulus region. With the decrease of particle handling capacity, the fluidization effect of multi-jets was improved. When the static bed depth was 0.165 m, the enhancement effect of multi-jets on the movement of particles in the spouted bed would be optimal. When the particle diameter was overly small, the fluidization effect of the side jet would be relatively low, while excessive particle diameter would weaken the fluidization effect of the side jet due to the rise in the inertia force of particles. The analysis of the average turbulent kinetic energy and radial velocity of the particles revealed that when the particle diameter is equal to 0.72 mm, the strengthening factor of movement of particles (η) reaches the peak, the turbulence fluctuation of particles in the annulus region reaches the highest, and the fluidization effect of side jets on the particles is the best.