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Updated: Jun 8, 2026
06:42
Magnetically Induced Rotating Rayleigh-Taylor Instability
Published on: March 3, 2017
Supertransient magnetohydrodynamic turbulence in Keplerian shear flows
Erico L Rempel1, Geoffroy Lesur, Michael R E Proctor
1Institute of Aeronautical Technology (IEFM/ITA), World Institute for Space Environment Research (WISER), São José dos Campos-SP 12228-900, Brazil. rempel@ita.br
Physical Review Letters
|September 28, 2010
Summary
This study investigates turbulence in magnetized Keplerian shear flows. Results show no clear transition to sustained turbulence, with transient lifetimes increasing exponentially with magnetic Reynolds number.
Area of Science:
- Plasma physics
- Astrophysical fluid dynamics
- Magnetohydrodynamics
Background:
- Turbulence in magnetized shear flows is crucial for astrophysical phenomena.
- Understanding the transition to turbulence is a fundamental challenge.
- Keplerian shear flows are common in accretion disks.
Purpose of the Study:
- To investigate the subcritical transition to turbulence in magnetized Keplerian shear flows.
- To determine the transition from decaying to sustained turbulence.
- To analyze the role of the magnetic Reynolds number (Rm) in this transition.
Main Methods:
- Utilizing a statistical approach.
- Performing three-dimensional numerical simulations of the shearing box equations.
- Simulating with zero net magnetic flux.
Main Results:
- No clear transition to sustained turbulence was observed.
- The average lifetime of transient turbulent states increases exponentially with Rm.
- The observed behavior aligns with a type-II supertransient law.
Conclusions:
- The transition to turbulence in these systems is not a sharp threshold.
- Supertransient behavior dominates, characterized by long-lived turbulent transients.
- Further research is needed to fully understand the implications for astrophysical systems.
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