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Updated: Jun 21, 2026
06:42
Magnetically Induced Rotating Rayleigh-Taylor Instability
Published on: March 3, 2017
Nonlinear cascades in two-dimensional turbulent magnetoconvection
Dan Skandera1, Wolf-Christian Müller
1Max-Planck-Institut für Plasmaphysik, 85748 Garching, Germany.
Physical Review Letters
|August 8, 2009
Summary
This study reveals self-excited transitions between turbulent states in electrically conducting fluids, driven by magnetohydrodynamics and buoyancy. Cross helicity controls these dynamics, offering new insights into fluid behavior.
Area of Science:
- Fluid dynamics
- Plasma physics
- Magnetohydrodynamics
Background:
- Turbulent convection in electrically conducting fluids is complex.
- Understanding spectral transport dynamics is crucial.
Purpose of the Study:
- Investigate spectral transport in 2D turbulent convection.
- Analyze the interplay of magnetohydrodynamics and buoyancy forces.
- Report the novel self-excited transitions between turbulent states.
Main Methods:
- Direct numerical simulations.
- Magnetohydrodynamic Boussinesq approximation.
Main Results:
- Observed quasioscillations between two distinct turbulent regimes.
- Identified nonlinear magnetohydrodynamic interactions and buoyancy forces as dominant factors.
- Demonstrated the control of cross helicity (H;{C}) over state changes.
Conclusions:
- The self-excited switching of turbulent states is a novel finding.
- Cross helicity is a key controlling invariant.
- Convective driving and nonlinear spectral transfer explain the observed dynamics.
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