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Updated: Jun 5, 2026
06:42
Magnetically Induced Rotating Rayleigh-Taylor Instability
Published on: March 3, 2017
Structures in magnetohydrodynamic turbulence: detection and scaling.
V M Uritsky1, A Pouquet, D Rosenberg
1Physics and Astronomy Department, University of Calgary, Calgary, Alberta T2N1N4, Canada.
Physical Review. E, Statistical, Nonlinear, and Soft Matter Physics
|January 15, 2011
Summary
Cluster analysis reveals similar statistical properties for turbulent current and vorticity structures in decaying magnetohydrodynamic turbulence. These findings highlight self-organized criticality in the dissipative range and suggest turbulence dynamics govern the inertial range.
Area of Science:
- * Physics
- * Fluid Dynamics
- * Plasma Physics
Background:
- * Decaying three-dimensional magnetohydrodynamic (MHD) turbulence is investigated in the absence of an imposed magnetic field.
- * Simulations utilize a magnetic Prandtl number of unity and high-resolution grids (up to 1536³).
- * Initial conditions include Orszag-Tang vortex and Arn'old-Beltrami-Childress configurations.
Purpose of the Study:
- * To systematically analyze statistical properties of turbulent current and vorticity structures using cluster analysis.
- * To compare these properties across different initial conditions and simulation snapshots.
- * To investigate the influence of Reynolds number and velocity-magnetic field correlations on structure statistics.
Main Methods:
- * Numerical simulations of decaying 3D MHD turbulence.
- * Cluster analysis applied to identify and statistically characterize turbulent structures.
- * Analysis of simulation data at two time snapshots after peak dissipation.
Main Results:
- * Cluster analysis successfully identified over 8000 structures per snapshot.
- * Statistical properties and scaling laws of current and vorticity clusters were remarkably similar across different conditions.
- * Self-organized criticality was identified in the dissipative scales, with a distinct scaling in the inertial range.
Conclusions:
- * The statistical behavior of turbulent current and vorticity structures is consistent across different initial conditions and simulation times.
- * Dissipative scales exhibit self-organized criticality, while inertial scales may be governed by turbulence dynamics.
- * Intermittency is proposed to result from the propagation of local instabilities.
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