基于CFD-DEM的超细碳酸钙螺旋输送仿真分析  

Simulation analysis of ultrafine calcium carbonate spiral transportation based on CFD-DEM

作　　者：蔡文源 王利强 徐立敏 CAI Wenyuan;WANG Liqiang;XU Limin(Jiangsu Key Laboratory of Advanced Food Manufacturing Equipment and Technology,School of Mechanical Engineering,Jiangnan University,Wuxi 214122,China;Jiangsu Innovative Packaging Technology Co.,Ltd.,Yangzhou,225600,China)

机构地区：[1]江南大学江苏省食品先进制造装备技术重点实验室,机械工程学院,江苏无锡214122 [2]江苏创新包装科技有限公司,江苏扬州225600

出　　处：《中国粉体技术》2024年第3期100-111,共12页China Powder Science and Technology

基　　金：中央高校基本科研业务费专项资金项目,编号:JUSRP21115;江苏省食品先进制造装备技术重点实验室自主研究课题资助项目,编号:FMZ202304。

摘　　要：【目的】为提高螺旋输送机的输送效率,降低输送机的功耗与磨损,探究在不同进料速率、螺旋轴转速与几何体摩擦系数下,超细碳酸钙在水平变径变距螺旋输送机内的颗粒流动状态、出口质量流量、输送机功耗与磨损分布。【方法】使用计算流体动力学(computational fluid dynamics,CFD)与离散单元法(discrete element method,DEM)双向耦合数值模拟的方法,对螺旋输送机在不同转速下的质量流率进行分析对比,验证数值模型的正确性。【结果】摩擦系数对颗粒的运动有较大影响,颗粒流的轴向速度峰值和质量流率峰值随着摩擦系数的增加先增大再减小;随着下料速度和摩擦系数的增大,输送机功率明显增大,且摩擦系数在高进料速度与低转速的情况下对功耗的影响相对于低进料速度和高转速更加明显;磨损较严重的区域集中在下料口处的螺旋轴与螺旋叶片的边缘处。【结论】简单增大或减小摩擦系数并不能提高颗粒的轴向速度和质量流量,而是存在一个局部最优参数组合;适当地提高转速能够减小颗粒密实度与颗粒停留时间,从而减小输送机的功耗与几何体磨损。Objective As an important inorganic non-metallic powder material,ultrafine calcium carbonate is widely used in plastics,rubber,coatings,and paper making,etc.Due to its extremely small particle size and adhesive nature,there are difficulties in its conveying process leading to lower conveying efficiency and increased equipment wear.Therefore,it requires improved design and operation of conveying equipment.Screw conveyor,as an efficient and widely used solid material conveying equipment,is characterized by its simple structure,low maintenance costs,and ability to convey materials in horizontal,inclined,or vertical directions.With the advancement of computer simulation technology,the discrete element method(DEM)technique has become an important tool to study the particle flow and interactions in screw conveyor conveying process.Current research on CFD-DEM coupling method for screw conveyors typically focuses on operational parameters for large particle materials.However,they overlook investigations into the role of geometric friction coefficients in the ultrafine powder conveying.In order to improve the efficiency of screw conveyors and reduce power consumption and wear,the study was conducted to examine the particle flow state,outlet mass flow rate,conveyor power consumption,and wear distribution of ultrafine calcium carbonate in a horizontal screw conveyor with variable diameter and pitch.This study provided theoretical and technical support for effective transport of ultrafine powders,as well as new perspectives and methodological foundation for engineering applications and scientific research in related fields.Methods In this study,we adopted the CFD-DEM coupling method,using FLUENT,a fluid dynamics software,and EDEM,a discrete element software,to explore the gas-solid two-phase flow characteristics of ultrafine calcium carbonate powder during horizontal conveying with variable diameter and pitch of the spiral.It also explored the effects of different operational and geometric parameters on the conveying process

关 键 词：超细碳酸钙 计算流体动力学 离散单元法 螺旋输送机 颗粒流动 

分 类 号：TB44[一般工业技术] TH224[机械工程—机械制造及自动化]