Radial velocity distributions of two kinds of glass beads, belonging to Geldart type B classification, were investigated at different axial sections in the bubbling fluidized bed with an inner diameter of 0.185 m under different superficial gas velocities. Local particle velocities were measured by using the PV-5A fiber-optical probe. The experimental results indicate that the radial distribution of particle velocities in the bed bottom zone is irregular, where the design of the distributor is dominated. When the axial section is far from the distributor, the particle velocities are higher in the center than those near the wall within the bed, which becomes obvious with increasing superficial gas velocity. Meanwhile, there exists a transitional zone between the above two zones, where the effect of the distributor tends to be weakened. This leads that the radial distribution of particle velocities is regular. Moreover, the amplitude of particle velocity at the same axial position changes sharply with an increase of superficial gas velocity.
2008, 21 (3):
5-8.
