Imperial College London
Portrait Picture

Professor Omar K. Matar, FREng

Faculty of Engineering, Department of Chemical Engineering

Head of Department of Chemical Engineering
 
 
 
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Contact

 

+44 (0)20 7594 9618o.matar Website

 
 
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Assistant

 

Mr Avery Kitchens +44 (0)20 7594 6263

 
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Location

 

305 ACEACE ExtensionSouth Kensington Campus

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Summary

 

Publications

Citation

BibTex format

@article{Kahouadji:2022:10.1017/flo.2022.24,
author = {Kahouadji, L and Liang, F and Valdes, JP and Shin, S and Chergui, J and Juric, D and Craster, RV and Matar, OK},
doi = {10.1017/flo.2022.24},
journal = {Flow, Turbulence and Combustion},
pages = {1--20},
title = {The transition to aeration in turbulent two-phase mixing in stirred vessels},
url = {http://dx.doi.org/10.1017/flo.2022.24},
volume = {2},
year = {2022}
}
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RIS format (EndNote, RefMan)

TY  - JOUR
AB  - We consider the mixing dynamics of an air–liquid system driven by the rotation of a pitched blade turbine (PBT) inside an open, cylindrical tank. To examine the flow and interfacial dynamics, we use a highly parallelised implementation of a hybrid front-tracking/level-set method that employs a domain-decomposition parallelisation strategy. Our numerical technique is designed to capture faithfully complex interfacial deformation, and changes of topology, including interface rupture and dispersed phase coalescence. As shown via transient, a three-dimensional (3-D) LES (large eddy simulation) using a Smagorinsky–Lilly turbulence model, the impeller induces the formation of primary vortices that arise in many idealised rotating flows as well as several secondary vortical structures resembling Kelvin–Helmholtz, vortex breakdown, blade tip vortices and end-wall corner vortices. As the rotation rate increases, a transition to ‘aeration’ is observed when the interface reaches the rotating blades leading to the entrainment of air bubbles into the viscous fluid and the creation of a bubbly, rotating, free surface flow. The mechanisms underlying the aeration transition are probed as are the routes leading to it, which are shown to exhibit a strong dependence on flow history.
AU  - Kahouadji,L
AU  - Liang,F
AU  - Valdes,JP
AU  - Shin,S
AU  - Chergui,J
AU  - Juric,D
AU  - Craster,RV
AU  - Matar,OK
DO  - 10.1017/flo.2022.24
EP  - 20
PY  - 2022///
SN  - 0003-6994
SP  - 1
TI  - The transition to aeration in turbulent two-phase mixing in stirred vessels
T2  - Flow, Turbulence and Combustion
UR  - http://dx.doi.org/10.1017/flo.2022.24
UR  - https://www.cambridge.org/core/journals/flow/article/transition-to-aeration-in-turbulent-twophase-mixing-in-stirred-vessels/6C39B2AB37A3A544A803DE089B3A0A70
UR  - http://hdl.handle.net/10044/1/100331
VL  - 2
ER  -
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