摘要
提出区域覆盖法,实现了正交结构化网格(DEM网格)与非规则网格(Fluent网格)的快速耦合,通过减少颗粒搜索量的方法,提高计算效率;采用向量法高效、精确定位颗粒在非规则网格内的位置,进而形成基于非规则网格的CFD-DEM数值模拟平台。在宽和高分别为250mm和800mm的二维多埋管流化床内对颗粒流动行为进行了数值模拟研究。结果表明:基于区域覆盖法建立的CFD-DEM模型能够模拟具有复杂几何结构流化床内的气固流动行为;多埋管流化床内的颗粒上升流磨损埋管的迎风面,在背风面形成颗粒浓度较低的区域;而颗粒下降流对埋管的影响与上升流的影响相反;多埋管流化床内的颗粒行为可划分为颗粒上升流、颗粒下降流、颗粒循环流和无颗粒区。
The domain coverage method(DCM)was proposed to couple orthogonal structured DEM mesh with irregular Fluent mesh.DCM increased calculation efficiency by decreasing particle searching capacity for each Fluent cell.Particles were positioned in irregular Fluent cells with the vector method.The CFD-DEM platform was built based on DCM.And then solids behavior was studied in a fluidized bed 250 mm in bed width and 800mm in bed height with multi-immersed tubes.Simulation results showed that the proposed CFD-DEM model based on DCM could simulate gas-solids flow behavior in a fluidized bed with complex geometries.Particles moving upward collides with windward side of the fluidized bed and the other side formed a region with low solids fraction.Particles moving downward had an opposite effect on solids behavior comparing with particles moving upward.Solids behavior could be expressed into four regions:solids flow moving upward,solids flow moving downward,solids flow moving circularly and no solids region.
出处
《化工学报》
EI
CAS
CSCD
北大核心
2013年第8期2788-2793,共6页
CIESC Journal
基金
山东省自然科学基金项目(ZR2011EL042)~~
关键词
流化床
区域覆盖法
非规则网格
埋管
fluidized bed
domain coverage method
irregular mesh
immersed tube