Investigation of dense slurry suspensions with coaxial mixers:Influences of design variables through tomography and mathematical modelling  

作　　者：Prakash Mishra Farhad Ein-Mozaffari 

机构地区：[1]Department of Chemical Engineering,Ryerson University,Toronto,M5B 2K3,Canada

出　　处：《Particuology》2022年第6期1-16,共16页颗粒学报（英文版）

基　　金：Financial support by the Natural Sciences and Engineering Research Council of Canada(NSERC)is greatly appreciated.

摘　　要：The coaxial mixers enhance the suspension of concentrated slurries in an agitated reactor.In this research work,the complex slurry suspension and dissemination behavior in a coaxial slurry mixing system(comprised of a close clearance anchor rotating with a low speed and an inner axial impeller rotating with a high speed)was analyzed employing ERT(electrical resistance tomography,a non-intrusive flow visualization technique),and computational fluid dynamics(CFD).The numerical models were validated by comparing the axial solid concentration profiles generated using the ERT data and the CFD simulation results.The influences of various important parameters such as the diameter of the inner axial impeller,the inner impeller type,and the inner impeller spacing on the hydrodynamic characteristics of the slurry suspensions in a coaxial mixing vessel were thoroughly analyzed.The radial and axial velocity profiles of solid particles were generated using the validated mathematical models.The assessment of energy loss due to the solid-solid collisions,the particle-fluid frictions,and the particle-vessel wall collisions was conducted.The evaluation of optimum inner impeller clearance and inner impeller diameter is essential to attain a high degree of solids suspension and dissemination in a coaxial slurry mixing system.

关 键 词：Coaxial mixer Slurry suspension HOMOGENEITY Mixing index Electrical resistance tomography(ERT) Computational fluid dynamics(CFD) 

分 类 号：O35[理学—流体力学]