The Library
Numerical simulation of a confined cavitating gas bubble driven by ultrasound
Tools
Mifsud, Jacqueline, Lockerby, Duncan A., Chung, Yongmann M. and Jones, Gordon (2021) Numerical simulation of a confined cavitating gas bubble driven by ultrasound. Physics of Fluids, 33 (12). 122114 . doi:10.1063/5.0075280 ISSN 1070-6631.
|
PDF
WRAP-numerical-simulation-confined-cavitating-gas-bubble-driven-ultrasound-Mifsud-2022.pdf - Accepted Version - Requires a PDF viewer. Download (25Mb) | Preview |
Official URL: https://doi.org/10.1063/5.0075280
Abstract
This work investigates the flow disturbance generated by an ultrasonically-driven gas bubble confined in a narrow gap over one acoustic cycle. Here, we provide a more accurate representation of ultrasonic cleaning by implementing a Volume-of-Fluid model in OpenFOAM that simulates the ultrasound as a sinusoidally time-varying pressure boundary condition. A modified Rayleigh-Plesset equation is solved to select an acoustic forcing that instigates bubble collapse. Simulations reveal the interaction between the inflow from the acoustic forcing and the flow deflected by the confining walls intensifies the strength of the self-piercing micro-jet(s), and consequently of the unsteady boundary layer flow, compared to the traditional collapse near a single rigid wall. Depending on the gap height and the position of bubble inception inside the gap, three distinct collapse regimes involving dual-jets or directed-jets are identified, each resulting in a different shear-stress footprint on the confining boundaries. Plots of the spatio-temporal evolution of the shear flow (that is difficult to measure experimentally) reveal peak shear-stress magnitudes at collapse that are double those reported for an undriven laser-induced bubble in similar geometric confinement. This twofold increase is attributed to the ultrasonic signal driving the collapse. Surprisingly, in our simulations we have not encountered a transferred-jet regime previously observed for an unforced bubble collapsing in a similar configuration. This unexpected finding highlights the different physics involved in modelling acoustically-driven bubbles compared to the conventional laser-induced bubbles used in experiments.
Item Type: | Journal Article | |||||||||
---|---|---|---|---|---|---|---|---|---|---|
Subjects: | Q Science > QA Mathematics Q Science > QC Physics T Technology > TA Engineering (General). Civil engineering (General) |
|||||||||
Divisions: | Faculty of Science, Engineering and Medicine > Engineering > Engineering | |||||||||
Library of Congress Subject Headings (LCSH): | Computational fluid dynamics , Turbulence -- Simulation methods, Turbulence -- Mathematical models, Boundary layer, Shear flow -- Mathematical models, Shear flow -- Simulation methods, Cavitation, Hydrodynamics | |||||||||
Journal or Publication Title: | Physics of Fluids | |||||||||
Publisher: | American Institute of Physics | |||||||||
ISSN: | 1070-6631 | |||||||||
Official Date: | 29 December 2021 | |||||||||
Dates: |
|
|||||||||
Volume: | 33 | |||||||||
Number: | 12 | |||||||||
Article Number: | 122114 | |||||||||
DOI: | 10.1063/5.0075280 | |||||||||
Status: | Peer Reviewed | |||||||||
Publication Status: | Published | |||||||||
Reuse Statement (publisher, data, author rights): | The following article has been accepted by Physics of Fluids. After it is published, it will be found at https://aip.scitation.org/journal/phf | |||||||||
Access rights to Published version: | Restricted or Subscription Access | |||||||||
Date of first compliant deposit: | 7 December 2021 | |||||||||
Date of first compliant Open Access: | 8 December 2021 | |||||||||
RIOXX Funder/Project Grant: |
|
|||||||||
Related URLs: |
Request changes or add full text files to a record
Repository staff actions (login required)
View Item |
Downloads
Downloads per month over past year