Noise-sustained convective instability in a magnetized Taylor-Couette flow

Journal Article · Tue Jan 01 04:00:00 EST 2008 · The Astrophysical Journal

OSTI ID:960597

Liu, Wei ^[1]

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1. Los Alamos National Laboratory

The helical magnetorotational instability of the magnetized Taylor-Couette flow is studied numerically in a finite cylinder. A distant upstream insulating boundary is shown to stabilize the convective instability entirely while reducing the growth rate of the absolute instability. The reduction is less severe with larger height. After modeling the boundary conditions properly, the wave patterns observed in the experiment turn out to be a noise-sustained convective instability. After the source of the noise resulted from unstable Ekman and Stewartson layers is switched off, a slowly-decaying inertial oscillation is observed in the simulation. We reach the conclusion that the experiments completed to date have not yet reached the regime of absolute instability.

• Research Organization: Los Alamos National Laboratory (LANL)
• Sponsoring Organization: DOE
• DOE Contract Number: AC52-06NA25396
• OSTI ID: 960597
• Report Number(s): LA-UR-08-05429; LA-UR-08-5429
• Journal Information: The Astrophysical Journal, Journal Name: The Astrophysical Journal; ISSN ASJOAB; ISSN 0004-637X
• Country of Publication: United States
• Language: English

Related Subjects

71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
ACCRETION DISKS
BOUNDARY CONDITIONS
COUETTE FLOW
GROWTH
HEIGHT
INSTABILITY
LAYERS
MAGNETOHYDRODYNAMICS
NOISE
NUMERICAL SOLUTION
OSCILLATIONS
REDUCTION
SIMULATION