摘要
针对Kenics型静态混合器内固体颗粒在幂律流体中的孤岛现象的产生机理进行研究。运用Fluent数值模拟固相颗粒与CMC水溶液在Kenics静态混合器中的混合过程,并利用浓度变异系数(COV)对颗粒分布特性进行量化分析。研究表明:提高流体表观黏度和流体入口速度,颗粒停留时间缩短,COV值降低,混合效果提高。在第4~8个扭旋叶片中间截面上均形成了两对对称的无粒子孤岛,降低流体表观黏度和提高流体入口速度,孤岛边界更清晰。扭旋叶片诱导的内流涡旋和近壁面涡旋有较高的涡量,涡旋中心局域形成无粒子孤岛,相邻叶片交错区域,随着涡旋耗散孤岛消失。
The cause of island without particle in the power-law fluid was investigated in Kenics static mixers.The mixing process of solid particles and CMC solution with three concentrations in Kenics static mixer was numerically simulated by Fluent,and the concentration coefficient of variation(COV)was used to quantitatively analyze the particle distribution.On the middle cross-section of 4th~8th twist blades,two pairs of island without particle were formed in power-law fluid.In this study,the residence time of particle was shortened and the boundary of island was clearer when the apparent viscosity of power-law fluid reduced and the velocity of mixer inlet increased.But the lower COV value and the better mixing effect were obtained with increasing apparent viscosity and flow velocity.The vorticity absolute value was high in internal flow vortex and near-wall vortex induced by the twisted blade,and there were islands without particle in the center region of vortices.The island without particle disappeared with the vortex dissipation near the interface of adjacent blades and the outlet of twisted blades.
作者
张静
蒋灿
周承昊
王瑶
龚斌
ZHANG Jing;JIANG Can;ZHOU Chenghao;WANG Yao;GONG Bin(College of Mechanical and Power Engineering,Shenyang University of Chemical Technology,Shenyang Liaoning 110142,China)
出处
《当代化工》
CAS
2024年第3期695-700,725,共7页
Contemporary Chemical Industry
基金
辽宁省应用基础研究计划项目(项目编号:2022JH2/101300077)
辽宁省教育厅自然科学基础项目(项目编号:LJ2020016)。
关键词
Kenics静态混合器
幂律流体
液固混合
变异系数
无粒子孤岛
Kenics static mixer
Power law fluid
Liquid-solid mixing
Coefficient of variation
Island without particle
作者简介
张静(1971-),女,辽宁省沈阳市人,教授,博士在读,研究方向:分离和混合过程强化。E-mail:2501474185@qq.com;通信作者:龚斌(1973-),男,教授,博士,研究方向:化工过程强化。E-mail:gbsyhgdx@163.com。
