Mixing viscoplastic fluids in stirred vessels over multiple scales: A combined experimental and CFD approach
File(s)
Accepted version
Author(s)
Type
Journal Article
Abstract
Dye visualisation techniques and CFD are used to characterise the flow of viscoplastic CarbopolTM solutions in stirred vessel systems over multiple scales. Centrally-mounted, geometrically-similar Rushton turbine (RT) impellers are used to agitate various Carbopol 980 (C980) fluids. The dimensionless cavern diameters, Dc/D, are scaled against a combination of dimensionless parameters: Rem-0.3Rey0.6n-0.1ks-1, where Rem, Rey, n and ks are the modified power-law Reynolds number, yield stress Reynolds number, flow behaviour index and impeller geometry constant, respectively. Excellent collapse of the data is demonstrated for the fluids and flows investigated. Additional data are collected using a pitched-blade turbine (PBT) with cavern size similarity being shown between the RT and PBT datasets. These results are important in the context of scale-up/scale-down mixing processes in stirred vessels containing complex fluids and can be used to show that flow similarity can be achieved in these systems if the processes are scaled appropriately.
Date Issued
2019-11-23
Date Acceptance
2019-07-19
Citation
Chemical Engineering Science, 2019, 208
ISSN
1873-4405
Publisher
Elsevier
Journal / Book Title
Chemical Engineering Science
Volume
208
Sponsor
Engineering and Physical Sciences Research Council
Syngenta
Syngenta Ltd
Grant Number
1855724
N/A
Subjects
Science & Technology
Technology
Engineering, Chemical
Engineering
Caverns
Mixing
Scaling
Stirred vessel
Viscoplastic
Visualisation
SHEAR-THINNING FLUIDS
NON-NEWTONIAN FLUIDS
LASER-INDUCED FLUORESCENCE
HERSCHEL-BULKLEY FLUIDS
POSSESSING YIELD-STRESS
PSEUDOPLASTIC FLUIDS
CAVERN SIZES
RHEOLOGICAL PROPERTIES
CARBOPOL GELS
FLOW VISUALIZATION
Chemical Engineering
0904 Chemical Engineering
0913 Mechanical Engineering
0914 Resources Engineering and Extractive Metallurgy
Publication Status
Published
Article Number
ARTN 115129
Date Publish Online
2019-07-27