摘要
采用离散元方法-计算流体力学(DEM-CFD)对耦合边界下A类颗粒流化床特性进行模拟。讨论了在床底的表观速度取决于流场情况下,不同进口流速时该类颗粒的流化状态。分析了流动与颗粒运动的相互作用,及其对最小流化速度和最小气泡速度的影响。发现与均匀床底的表观速度相比,当床底的流动速度取决于流动与颗粒运动耦合时,床体的稳定性变差,床底的速度分布呈现不均匀,局部更早出现气泡,并沿着该位置的轴向向床顶面发展,形成沟流,而此时其它部位会产生死区。
The simulation study of gas-fluidization characteristics for Group＇s A particles with couple＇s boundary condition was carried out by a method combining discrete element method and computational fluid dynamics （CFD-DEM）. The characteristics of fluidization of this class particles was analyzed under the different velocities with the bed bottom＇s superficial velocity determined from the velocity field and not from a uniform value. The interaction between the flow and particle motions and their influence to the minimal fluidization velocity and minimal bubble velocity were analyzed. It was found that bed stability would be worse in couple＇s condition compared with the uniform value and the velocity distribution in the bed bottom was no uniform and the bubbles happened earlier in some place where fluid channeling formed and dead zones come into being in other palce.
出处
《化学反应工程与工艺》
CAS
CSCD
北大核心
2010年第5期411-417,共7页
Chemical Reaction Engineering and Technology
关键词
流化床
A类颗粒
耦合边界
离散元方法
计算流体力学
数值模拟
fluidization stability
Group＇A particles
couple＇s boundary condition~ discrete elementmethod~ computational fluid dynamics
simulation
