Jetting from cavitation bubbles in viscous and confined liquids

Rapidly expanding and shrinking bubbles can produce high-speed jets that can clean nearby surfaces or deliver drugs into tissue and cells by applying shear stress. In this thesis, we use high-speed photography and numerical techniques to resolve the spatio-temporal distribution of shear stress. Shor...

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Main Author: Zeng, Qingyun
Other Authors: Yong Ee Hou
Format: Thesis-Doctor of Philosophy
Language:English
Published: Nanyang Technological University 2020
Subjects:
Online Access:https://hdl.handle.net/10356/137043
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Institution: Nanyang Technological University
Language: English
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spelling sg-ntu-dr.10356-1370432023-02-28T23:48:43Z Jetting from cavitation bubbles in viscous and confined liquids Zeng, Qingyun Yong Ee Hou School of Physical and Mathematical Sciences eehou@ntu.edu.sg Engineering::Mechanical engineering::Fluid mechanics Science::Physics Rapidly expanding and shrinking bubbles can produce high-speed jets that can clean nearby surfaces or deliver drugs into tissue and cells by applying shear stress. In this thesis, we use high-speed photography and numerical techniques to resolve the spatio-temporal distribution of shear stress. Short-lived but extremely high stresses of 100kPa are found in simulations due to the spreading of the jet onto the boundary. By confining the bubble within a narrow gap consisting of two rigid plates the jet speed and direction can be altered and an intriguing competition between viscous forces and inertia is resolved. When the bubble is confined within a viscous droplet jetting is observed too, but created through the spherical Rayleigh-Taylor instability. Stability analysis and numerical simulations demonstrate the working mechanism for aqueous liquids as well as for liquid metals. The later droplets are used for extreme UV production in the semiconductor industry. Doctor of Philosophy 2020-02-14T05:28:30Z 2020-02-14T05:28:30Z 2020 Thesis-Doctor of Philosophy Zeng, Q. (2020). Jetting from cavitation bubbles in viscous and confined liquids. Doctoral thesis, Nanyang Technological University, Singapore. https://hdl.handle.net/10356/137043 10.32657/10356/137043 en This work is licensed under a Creative Commons Attribution-NonCommercial 4.0 International License (CC BY-NC 4.0). application/pdf Nanyang Technological University
institution Nanyang Technological University
building NTU Library
continent Asia
country Singapore
Singapore
content_provider NTU Library
collection DR-NTU
language English
topic Engineering::Mechanical engineering::Fluid mechanics
Science::Physics
spellingShingle Engineering::Mechanical engineering::Fluid mechanics
Science::Physics
Zeng, Qingyun
Jetting from cavitation bubbles in viscous and confined liquids
description Rapidly expanding and shrinking bubbles can produce high-speed jets that can clean nearby surfaces or deliver drugs into tissue and cells by applying shear stress. In this thesis, we use high-speed photography and numerical techniques to resolve the spatio-temporal distribution of shear stress. Short-lived but extremely high stresses of 100kPa are found in simulations due to the spreading of the jet onto the boundary. By confining the bubble within a narrow gap consisting of two rigid plates the jet speed and direction can be altered and an intriguing competition between viscous forces and inertia is resolved. When the bubble is confined within a viscous droplet jetting is observed too, but created through the spherical Rayleigh-Taylor instability. Stability analysis and numerical simulations demonstrate the working mechanism for aqueous liquids as well as for liquid metals. The later droplets are used for extreme UV production in the semiconductor industry.
author2 Yong Ee Hou
author_facet Yong Ee Hou
Zeng, Qingyun
format Thesis-Doctor of Philosophy
author Zeng, Qingyun
author_sort Zeng, Qingyun
title Jetting from cavitation bubbles in viscous and confined liquids
title_short Jetting from cavitation bubbles in viscous and confined liquids
title_full Jetting from cavitation bubbles in viscous and confined liquids
title_fullStr Jetting from cavitation bubbles in viscous and confined liquids
title_full_unstemmed Jetting from cavitation bubbles in viscous and confined liquids
title_sort jetting from cavitation bubbles in viscous and confined liquids
publisher Nanyang Technological University
publishDate 2020
url https://hdl.handle.net/10356/137043
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