[en] This paper presents an experimental analysis of the evolution with time of the flow pattern in a stirred tank equipped with a rotor-stator mixer, when mixing a time dependent non-Newtonian fluid. Particle image velocimetry (PIV) is used to determine 2D velocity maps. Polyacrylamide (PAAm) aqueous solution is used as model of time dependent shear thinning fluids. Creep compliance and recovery tests are performed to follow the evolution of the fluid rheology, from a viscoelastic behaviour to a purely viscous one. This indicates mixing has almost completely destroyed the initial network structure of the non-Newtonian fluid. The evolution of the flow pattern with the mixing time is compared with the flow patterns obtained in presence of Newtonian fluids as water and glycerol aqueous solution.
Disciplines :
Chemical engineering
Author, co-author :
Fransolet, E.; Lab. de Génie Chimique, B6c, Dept. de Chimie Appliquée, Université de Liège, Liège B4000, Belgium
Marchot, Pierre ; Université de Liège - ULiège > Department of Chemical Engineering > Génie chimique - Systèmes polyphasiques
Toye, Dominique ; Université de Liège - ULiège > Department of Chemical Engineering
Crine, Michel ; Université de Liège - ULiège > Department of Chemical Engineering
Language :
English
Title :
Flow pattern evolution with time mixing of non-newtionian fluid in a stirred tank using particle image velocimetry
Publication date :
2004
Event name :
Proceedings of the 7th Biennial Conference on Engineering Systems Design and Analysis - 2004
Event place :
Manchester
Event date :
19 July 2004 through 22 July 2004
Audience :
International
Main work title :
Proceedings of the 7th Biennial Conference on Engineering Systems Design and Analysis, ESDA 2004
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