空气重介流化床介质流动和床层密度分布研究

Numerical Simulation of Solid Flows and Density Distribution in Air Dense Medium Fluidized Bed (ADMFB)

建立了空气重介质流化床的多相流体力学模型 ,基于选矿实验室的二维床 ( 60 cm× 1 .2cm)求解了介质速度和密度的分布 .结果表明 :模拟结果和实验结果符合性很好 .磁性介质在流化床内部呈现出中心上升边壁下降的流动趋势 .固体颗粒的运动速度很小 ,在床内的大部分区域其速度在 - 40～ 40 mm/ s之间 .在气体的表观速度为 0 .1 5 7m/ s时 ,床层密度值为 1 .96± 0 .0 3。

Model of ADMFB using multi fluid hydrodynamic theories was established. The velocity and the density distributions were obtained based on a 2d ADMFB(60 cm×1.2 cm) used in lab of coal preparation of CUMT. The results show that the computed data are in good agreement with the experimental data, and the flow pattern of dense medium is an ascending one near the center and a descending one near the wall. The solid velocity is very slow, within the range of -40~40 mm/s in most of the solid bed. The density of the bed is around 1.96 (±0.03) g/cm 3 at the inlet gas velocity of 0.157 m/s, and the density near the top is a little lower than that near the bottom.