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Magnetically Induced Rotating Rayleigh-Taylor Instability
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Suppressing shape instabilities to discover the Bjerknes force instability (L)
Mohammad A Alibakhshi1, R Glynn Holt
1Department of Mechanical Engineering, Boston University, 110 Cummington Street, Boston, Massachusetts 02215, USA. amin@bu.edu
The Journal of the Acoustical Society of America
|November 18, 2011
Summary
Increasing liquid viscosity may enable observation of bubble repulsion from acoustic pressure antinodes in sonoluminescence experiments. This could allow study of the Bjerknes force instability, which is typically masked by shape instabilities in water.
Area of Science:
- Acoustic cavitation
- Bubble dynamics
- Sonoluminescence
Background:
- Subresonant bubbles are theoretically repelled from pressure antinodes in acoustic fields.
- This instability is not observed under standard single bubble sonoluminescence (SBSL) conditions in water.
- Shape instabilities often dominate bubble behavior, masking other phenomena.
Purpose of the Study:
- To investigate if increasing host liquid viscosity can suppress bubble shape instabilities.
- To determine if higher viscosity allows SBSL experiments to be limited by the Bjerknes force instability.
- To explore conditions for observing bubble repulsion from acoustic pressure antinodes.
Main Methods:
- Theoretical investigation of bubble dynamics in viscous fluids under acoustic forcing.
- Analysis of the interplay between shape instabilities and Bjerknes force instability.
- Modeling of SBSL conditions in liquids with varying viscosity.
Main Results:
- Increased liquid viscosity is proposed as a method to suppress shape instabilities.
- This suppression could allow the Bjerknes force instability to become the dominant factor.
- Potentially enables observation of predicted bubble repulsion from pressure antinodes.
Conclusions:
- Modifying host liquid viscosity is a potential strategy to enable observation of bubble repulsion.
- This approach may allow SBSL experiments to probe the Bjerknes force instability.
- Further experimental validation is needed to confirm these theoretical predictions.
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