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Liquid-column sustainment driven by acoustic wave guiding
Nicolas Bertin1, Régis Wunenburger, Etienne Brasselet
1Centre de Physique Moléculaire Optique et Hertzienne, UMR CNRS 5798, Université Bordeaux I, 351 cours de la Libération, 33405 Talence Cedex, France.
Physical Review Letters
|January 15, 2011
Summary
We stabilized long liquid columns using acoustic radiation pressure, overcoming Rayleigh-Plateau instability limits. This acoustic feedback method enables the formation of highly elongated fluid structures.
Area of Science:
- Fluid dynamics
- Acoustics
- Surface physics
Background:
- The Rayleigh-Plateau instability limits the aspect ratio of free liquid columns.
- Controlling fluid interfaces at large aspect ratios is crucial for various applications.
Purpose of the Study:
- To investigate the formation and sustainment of liquid columns with aspect ratios exceeding the Rayleigh-Plateau instability threshold.
- To explore the use of acoustic radiation pressure for stabilizing elongated fluid structures.
Main Methods:
- Injecting an acoustic beam at the top of a liquid column to guide it along its length.
- Utilizing the passive feedback from acoustic radiation pressure on the column surface.
- Developing an analytical model to describe the interplay between acoustic wave guiding and surface forces (acoustic and capillary).
Main Results:
- Successfully formed and sustained liquid columns with significantly larger aspect ratios than predicted by the Rayleigh-Plateau instability.
- Demonstrated that acoustic radiation pressure can counteract capillary forces driving instability.
- Analytical model showed satisfactory agreement with experimental observations.
Conclusions:
- Acoustic radiation pressure provides an effective method for stabilizing long liquid columns.
- This technique allows for the creation of highly elongated fluid structures beyond conventional limits.
- The findings have implications for understanding and manipulating fluid interfaces in various scientific and engineering fields.
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