Effects of surface vortex on the drawdown and dispersion of floating particles in stirred tanks  

作　　者：Wentao Xu Yangbo Tan Meng Li Jianglong Sun De Xie Zeng Liu 

机构地区：[1]School of Naval Architecture,Ocean and Civil Engineering,Shanghai Jiao Tong University,Shanghai 200240,China [2]School of Naval Architecture and Ocean Engineering,Huazhong University of Science and Technology,Wuhan 430074,China [3]Collaborative Innovation Center for Advanced Ship and Deep-Sea Exploration,Shanghai 200240,China [4]Hubei Key Laboratory of Naval Architecture and Ocean Engineering Hydrodynamics,Wuhan 430074,China [5]Ocean Engineering.Huazhong University of Science and Technology,Wuhan 430074.China

出　　处：《Particuology》2020年第2期159-168,共10页颗粒学报（英文版）

基　　金：This work was supported by the National Natural Science Foun-dation of China under Project Nos.51474109,51609090,and 51679097.

摘　　要：The effects of surface vortex on the drawdown and dispersion of floating particles in stirred tanks were investigated.Particle distribution and power consumption were analyzed by experiments and numerical simulations in both baffled and unbaffled tanks agitated by a Rushton impeller.In unbaffled tanks,a non-aggregation rule was applied and the average dispersion index was found to serve as a reasonable prediction of the full drawdown of floating particles.The critical impeller speeds in an unbaffled tank were higher than those in a tank with vertical baffles.At each immersion depth in a baffled tank,particles distributed more uniformly and more power was consumed.Comparison of snapshots of the baffled and unbaffled tanks shows that the surface vortex increases the drawdown speed while it decreases the particle distribution uniformity and power consumption.Therefore,the use of baffles to suppress the surface vortex provides for a more uniform particle distribution in stirred tanks.

关 键 词：Stirred tank Surface vortex Solids drawdown Complete dispersion 

分 类 号：O35[理学—流体力学]