Wall collision of deformable bubbles in the creeping flow regime
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Published version
Author(s)
Denner, F
Type
Journal Article
Abstract
A systematic study of the hydrodynamic mechanisms governing the collision of a rising bubble with a solid wall in the creeping flow regime (Re <1) is presented, using direct numerical simulation. The presented results reveal self-similar aspects of the bubble–wall collision with respect to the capillary number, in particular of the film between the bubble and the wall as well as of the deformation and shape of the bubble. This similarity holds despite the extreme deformation of the bubble in some of the considered cases and is shown to be independent of the approach velocity and the fluid properties, indicating that the collision of a bubble with a solid wall in the creeping flow regime is governed by the balance of viscous stresses and surface tension, while the inertia of the bubble has a negligible influence. The timescale associated with the drainage of the film separating the bubble surface and the wall is also related to the viscocapillary balance, and is found to be independent of the size of the bubble. An empirical correlation is proposed based on the presented results to a priori estimate the drainage time of this film. Because the behaviour of a bubble during film drainage is quasi-stationary, the findings associated with film drainage also apply to bubble–wall collisions outside the remit of the creeping flow regime (Re >>).
Date Issued
2018-07-01
Date Acceptance
2018-02-14
Citation
European Journal of Mechanics - B/Fluids, 2018, 70, pp.36-45
ISSN
1873-7390
Publisher
Elsevier
Start Page
36
End Page
45
Journal / Book Title
European Journal of Mechanics - B/Fluids
Volume
70
Copyright Statement
© 2018 The Author. Published by Elsevier Masson SAS. This is an open access article under the CC BY
license (https://creativecommons.org/licenses/by/4.0/)
license (https://creativecommons.org/licenses/by/4.0/)
Sponsor
Engineering & Physical Science Research Council (EPSRC)
Grant Number
EP/M021556/1
Subjects
Science & Technology
Technology
Physical Sciences
Mechanics
Physics, Fluids & Plasmas
Physics
Bubble-wall collision
Bubble deformation
Film drainage
Creeping flow
Viscocapillary balance
THIN LIQUID-FILMS
CONSTANT APPROACH VELOCITY
CRITICAL THICKNESS
ARBITRARY MESHES
CAPILLARY WAVES
COLLIDING DROPS
REYNOLDS-NUMBER
SURFACE-TENSION
VOF METHOD
DRAINAGE
01 Mathematical Sciences
02 Physical Sciences
09 Engineering
Fluids & Plasmas
Publication Status
Published
Date Publish Online
2018-02-19