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Updated: May 28, 2026
06:42
Magnetically Induced Rotating Rayleigh-Taylor Instability
Published on: March 3, 2017
Effect of a capillary meniscus on the Faraday instability threshold
1PMMH, École Supérieure de Physique et de Chimie Industrielles, 75231 Paris, France.
The European Physical Journal. E, Soft Matter
|October 18, 2011
Summary
The Faraday instability threshold in viscous liquids was experimentally measured. Smaller containers altered critical acceleration and introduced eigenmodes, suggesting container walls influence fluid dynamics.
Area of Science:
- Fluid dynamics
- Instability phenomena
Background:
- Faraday instability is a pattern-forming instability in fluids subjected to vertical oscillations.
- The influence of container geometry on instability thresholds is not fully understood.
- Capillary effects at the fluid-interface boundary can significantly alter fluid behavior.
Purpose of the Study:
- To experimentally determine the threshold for Faraday instability in slightly viscous liquids.
- To investigate the effect of container size on the onset and characteristics of Faraday instability.
- To analyze the role of the capillary meniscus and viscous dissipation in confined fluids.
Main Methods:
- Experimental measurement of the critical acceleration for Faraday instability.
- Systematic variation of container diameter to study geometric effects.
- Observation and analysis of fluid surface patterns and eigenmodes.
- Development of a theoretical model incorporating viscous dissipation at container walls.
Main Results:
- The threshold for Faraday instability was experimentally measured for slightly viscous liquids.
- A decrease in container size led to an observed upset in critical acceleration.
- Eigenmodes were observed along the stability curve below a specific container diameter.
- The influence of the capillary meniscus on instability onset was highlighted.
Conclusions:
- Container size and associated capillary effects play a crucial role in the onset of Faraday instability.
- Viscous dissipation at container walls is a significant factor, particularly in smaller geometries.
- A proposed dissipation term accounts for wall effects, improving theoretical models.
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