Hydrodynamic behaviour of upflowing jet in fluidized bed: Velocity profiles of sand particles

摘要

The hydrodynamic behaviour of the submerging jet from nozzle in particulate medium by determining the velocity profiles is investigated in a 500 mm x 250 mm column filled with sand particles of 230 μm mean diameter and 2576 kg/m~3 density. The upflow jet air emerges from a nozzle with 15 mm diameter. Three nozzles with lengths of 80, 40 and Omm from above the distributor are used. The experiments show that the jet fundamental properties and the self-similarity of the reduced velocity profiles remain constant in the process. The self-similarity of the reduced velocity profiles is thus an intrinsic property in the steady-state flow of the jets in a particulate medium, whatever the longitudinal axis, the length of the nozzle, the jetting velocity and the bed state (aerated or fluidized).