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Published on: January 25, 2012
Rayleigh-taylor instability with magnetic fluids: experiment and theory
1Universite Paris 7-Denis Diderot, UFR de Physique (Case 7008), 2 place Jussieu, 75251 Paris Cedex 05, France and Laboratoire des Milieux Desordonnes et Heterogenes (Case 78), Universite Paris 6-UMR 7603 CNRS, 4 place Jussieu, 75252 Paris.
Summary
Experiments show that increasing magnetic fields suppress the wavelength of Rayleigh-Taylor instability between two liquids. The growth rate of interface deformation increases with the applied magnetic field.
Area of Science:
- Fluid dynamics
- Magnetohydrodynamics
- Instability phenomena
Background:
- The Rayleigh-Taylor instability occurs at the interface of two fluids of different densities when accelerated.
- Magnetic fields can influence fluid behavior, particularly in ferrofluids.
Purpose of the Study:
- To investigate the effect of an external magnetic field on Rayleigh-Taylor instability.
- To measure the wavelength and growth rate of the instability under varying magnetic fields.
Main Methods:
- Confining a dense magnetic liquid and a less dense immiscible liquid in a Hele-Shaw cell.
- Applying a magnetic field perpendicular to the Hele-Shaw cell.
- Measuring instability wavelength and growth rate as a function of magnetic field strength.
Main Results:
- The wavelength of the Rayleigh-Taylor instability decreases with increasing magnetic field.
- The growth rate of the interface deformation increases with the magnetic field.
- Interface amplitude grows exponentially in the early stage.
Conclusions:
- The study provides experimental data on magnetic field effects on Rayleigh-Taylor instability.
- Results are compared with theoretical predictions from linear stability analysis.
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