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Updated: Jul 26, 2026
06:42
Magnetically Induced Rotating Rayleigh-Taylor Instability
Published on: March 3, 2017
Rayleigh-Benard convection in a vertically oscillated fluid layer
1School of Physics, Georgia Institute of Technology, Atlanta, Georgia 30332-0430, USA.
Physical Review Letters
|October 4, 2000
Summary
This study details the first quantitative observations of fluid convection driven by heating and oscillation. Convection patterns exhibit harmonic or subharmonic responses, with novel coexisting states near a codimension-two point.
Area of Science:
- Fluid dynamics
- Nonlinear dynamics
- Pattern formation
Background:
- Convection is a fundamental heat transfer mechanism.
- Oscillatory forcing can significantly alter convection patterns.
- Understanding pattern selection in driven systems is crucial.
Purpose of the Study:
- To quantitatively observe convection in a fluid layer subjected to simultaneous bottom heating and vertical sinusoidal oscillation.
- To characterize the resulting convection patterns and their relationship to the driving frequency.
- To investigate novel patterns arising near a codimension-two point.
Main Methods:
- Experimental setup involving a fluid layer with controlled heating from below.
- Application of vertical sinusoidal oscillations at various frequencies.
- Quantitative observation and analysis of convection patterns using visualization techniques.
Main Results:
- Convection patterns near onset are modulated harmonically or subharmonically to the drive frequency.
- Single-frequency patterns show nearly solid-body rotations, with harmonic and subharmonic states rotating in opposite directions.
- Novel coexisting patterns with unique symmetries emerge near a codimension-two point, combining harmonic and subharmonic responses.
Conclusions:
- Linear stability analysis predictions for onset parameters align well with experimental results.
- Phase boundaries for coexisting patterns correlate with single-frequency marginal stability curves.
- The study reveals complex pattern selection phenomena in driven fluid systems.
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