搅拌槽内双层组合桨安装高度对气液混合特性影响的数模研究  

Numerical simulation research on influence of installation elevation of double-layer combined impeller on gas-liquid mixing property in stirred tank

作　　者：李盼盼 LI Pan-pan(Shanghai Investigation,Design&Research Institute Co.,Ltd.,Shanghai 200335,China)

机构地区：[1]上海勘测设计研究院有限公司,上海200335

出　　处：《广西水利水电》2021年第5期4-8,共5页Guangxi Water Resources & Hydropower Engineering

摘　　要：采用CFD方法求解气液两相流模型,对双层组合桨搅拌槽内的气液混合流动进行了数值模拟,其中上层桨是由8个不规则弧形叶片单元组成的倒伞形表面曝气转轮装置,下层桨是六直叶涡轮装置。控制方程采用速度压力耦合PISO(Pressure-Implicit with Splitting of Operators)算法求解,自由液面的捕捉采用VOF(Volume of fluid)法。根据模拟结果,分析了下层桨的安装高度对气相与液相的混合时间、搅拌槽内的流场特性以及气含率分布的影响规律:在本文模拟的3种工况下,随着下层桨安装高度的增加,混合时间减小,而气液混合区域增大,气体浓度沿轴向的变化率也增大。The gas-liquid two-phase flow model was solved by CFD method.The gas-liquid mixing flow in the stirred tank with double-layer combined impeller was studied by numerical simulation.The upper impeller is an inverse umbrella-shape surface aeration runner consisting of 8 irregular arc blade elements.The lower impeller is a six straight-blades vortex.The control equation is solved by PISO method.The free liquid surface is captured by VOF method.According to the results of simulation,the author analyzed the influence of installation elevation of lower impeller on the gas-liquid mixing time,flow field characteristics and gas holdup distribution in the stirred tank.Under the three operating conditions simulated,with the increase of installation elevation of the lower impeller,the mixing time decreases;the gas-liquid mixing area expands;the rate of change of gas concentration in axial direction increases.

关 键 词：表面曝气 组合桨 安装高度 混合时间 数值模拟 搅拌槽 

分 类 号：TQ051.72[化学工程]