Critical Magnetic Prandtl Number for Small-Scale Dynamo
نویسندگان
چکیده
منابع مشابه
Onset of Small-scale Turbulent Dynamo at Low Magnetic Prandtl Numbers
We study numerically the dependence of the critical magnetic Reynolds number Rmc for the turbulent smallscale dynamo on the hydrodynamic Reynolds number Re. We are interested in the regime of low magnetic Prandtl number Pm = Rm/Re < 1, which is relevant for stellar convective zones, protostellar disks, and laboratory liquidmetal experiments. The two asymptotic possibilities are Rmc → const as R...
متن کاملThe Onset of a Small-scale Turbulent Dynamo at Low Magnetic Prandtl Numbers
We study numerically the dependence of the critical magnetic Reynolds number Rmc for the turbulent smallscale dynamo on the hydrodynamic Reynolds number Re. The turbulence is statistically homogeneous, isotropic, and mirror–symmetric. We are interested in the regime of low magnetic Prandtl number Pm = Rm/Re < 1, which is relevant for stellar convective zones, protostellar disks, and laboratory ...
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We investigate the dynamo problem in the limit of small magnetic Prandtl number (Pm) using a shell model of magnetohydrodynamic turbulence. The model is designed to satisfy conservation laws of total energy, cross helicity and magnetic helicity in the limit of inviscid fluid and null magnetic diffusivity. The forcing is chosen to have a constant injection rate of energy and no injection of kine...
متن کاملMagnetic dynamo action at low magnetic Prandtl numbers.
Amplification of magnetic field due to kinematic turbulent dynamo action is studied in the regime of small magnetic Prandtl numbers. Such a regime is relevant for planets and stars interiors, as well as for liquid-metal laboratory experiments. A comprehensive analysis based on the Kazantsev-Kraichnan model is reported, which establishes the dynamo threshold and the dynamo growth rates for varyi...
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Axisymmetric stability of viscous resistive magnetized Couette flow is re-examined, with emphasis on flows that would be hydrodynamically stable according Rayleigh’s criterion: opposing gradients of angular velocity and specific angular momentum. In this regime, magnetorotational instability (MRI) may occur. The governing system in cylindrical coordinates is of tenth order. It is proved, by met...
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ژورنال
عنوان ژورنال: Physical Review Letters
سال: 2004
ISSN: 0031-9007,1079-7114
DOI: 10.1103/physrevlett.92.054502