Imperial College London

Professor Omar K. Matar

Faculty of EngineeringDepartment of Chemical Engineering

Vice-Dean (Education), Faculty of Engineering
 
 
 
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Contact

 

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

 
 
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Assistant

 

Miss Nazma Mojid +44 (0)20 7594 3918

 
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Location

 

506ACE ExtensionSouth Kensington Campus

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Summary

 

Publications

Citation

BibTex format

@article{Lei:2018:10.1017/jfm.2018.696,
author = {Lei, Q and Xie, Z and Pavlidis, D and Salinas, P and Veltin, J and Matar, O and Pain, C and Muggeridge, A and Gyllensten, A and Jackson, M},
doi = {10.1017/jfm.2018.696},
journal = {Journal of Fluid Mechanics},
pages = {1017--1039},
title = {The shape and motion of gas bubbles in a liquid flowing through a thin annulus},
url = {http://dx.doi.org/10.1017/jfm.2018.696},
volume = {285},
year = {2018}
}

RIS format (EndNote, RefMan)

TY  - JOUR
AB - We study the shape and motion of gas bubbles in a liquid flowing through a horizontal or slightly inclined thin annulus. Experimental data show that in the horizontal annulus, bubbles develop a unique ‘tadpole-like’ shape with a semi-circular cap and a highly stretched tail. As the annulus is inclined, the bubble tail tends to vanish, resulting in a significant decrease of bubble length. To model the bubble evolution, the thin annulus is conceptualised as a ‘Hele-Shaw’ cell in a curvilinear space. The three-dimensional flow within the cell is represented by a gap-averaged, two-dimensional model, which achieved a close match to the experimental data. The numerical model is further used to investigate the effects of gap thickness and pipe diameter on the bubble behaviour. The mechanism for the semi-circular cap formation is interpreted based on an analogous irrotational flow field around a circular cylinder, based on which a theoretical solution to the bubble velocity is derived. The bubble motion and cap geometry is mainly controlled by the gravitational component perpendicular to the flow direction. The bubble elongation in the horizontal annulus is caused by the buoyancy that moves the bubble to the top of the annulus. However, as the annulus is inclined, the gravitational component parallel to the flow direction becomes important, causing bubble separation at the tail and reduction in bubble length.
AU - Lei,Q
AU - Xie,Z
AU - Pavlidis,D
AU - Salinas,P
AU - Veltin,J
AU - Matar,O
AU - Pain,C
AU - Muggeridge,A
AU - Gyllensten,A
AU - Jackson,M
DO - 10.1017/jfm.2018.696
EP - 1039
PY - 2018///
SN - 0022-1120
SP - 1017
TI - The shape and motion of gas bubbles in a liquid flowing through a thin annulus
T2 - Journal of Fluid Mechanics
UR - http://dx.doi.org/10.1017/jfm.2018.696
UR - http://hdl.handle.net/10044/1/63495
VL - 285
ER -