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Related papers: Shear-driven magnetic buoyancy oscillations

200 papers

Numerical simulations of forced turbulence in elongated shearing boxes are carried out to demonstrate that a nonhelical turbulence in conjunction with a linear shear can give rise to a mean-field dynamo. Exponential growth of magnetic field…

We measured the static and dynamic (complex) shear viscosity of a single layer complex plasma by applying, respectively, a stationary and a periodically modulated shear stress induced by the light pressure of manipulating laser beams. Under…

Plasma Physics · Physics 2012-08-07 Peter Hartmann , Máté Csaba Sándor , Anikó Kovács , Zoltán Donkó

Intermittent large-scale high-shear flows are found to occur frequently and spontaneously in direct numerical simulations of statistically stationary turbulent Boussinesq magnetohydrodynamic (MHD) convection. The energetic steady-state of…

Solar and Stellar Astrophysics · Physics 2013-09-06 J. Pratt , A. Busse , W. -C. Mueller

We present a numerical study of turbulence and dynamo action in stratified shearing boxes with zero mean magnetic flux. We assume that the fluid obeys the perfect gas law and has finite (constant) thermal diffusivity. The calculations begin…

High Energy Astrophysical Phenomena · Physics 2015-06-11 G. Bodo , F. Cattaneo , A. Mignone , P. Rossi

We examine the effects of density stratification on magnetohydrodynamic turbulence driven by the magnetorotational instability in local simulations that adopt the shearing box approximation. Our primary result is that, even in the absence…

High Energy Astrophysical Phenomena · Physics 2014-11-20 S. W. Davis , J. M. Stone , M. E. Pessah

Hydrodynamic equations are used to identify the final state reached by a freely evolving granular gas above but close to its shear instability. The theory predicts the formation of a two bands shear state with a steady density profile.…

Statistical Mechanics · Physics 2009-11-13 J. Javier Brey , M. J. Ruiz-Montero , A. Dominguez

A novel large-scale dynamo mechanism, the magnetic shear-current effect, is discussed and explored. The effect relies on the interaction of magnetic fluctuations with a mean shear flow, meaning the saturated state of the small-scale dynamo…

High Energy Astrophysical Phenomena · Physics 2016-06-22 Jonathan Squire , Amitava Bhattacharjee

We present axisymmetric numerical calculations of the fluid flow induced in a spherical shell with inner sphere rotating and outer sphere stationary. A magnetic field is also imposed, consisting of particular linear combinations of axial…

Earth and Planetary Astrophysics · Physics 2010-08-03 Xing Wei , Rainer Hollerbach

Simulations of the magnetorotational instability (MRI) in a homogeneous shearing box have shown that the asymptotic strength of the magnetic field declines steeply with increasing resolution. Here I model the MRI driven dynamo as a large…

High Energy Astrophysical Phenomena · Physics 2011-02-11 Ethan T. Vishniac

The Vertical Shear Instability is an axisymmetric effect suggested to drive turbulence in the magnetically inactive zones of protoplanetary accretion disks. Here we examine its physical mechanism in analytically tractable ``minimal models"…

Earth and Planetary Astrophysics · Physics 2022-01-26 Ron Yellin-Bergovoy , Eyal Heifetz , Orkan M. Umurhan

The shear-current effect in a nonrotating homogeneous turbulent convection with a large-scale constant shear is studied. The large-scale velocity shear causes anisotropy of turbulent convection, which produces the mean electromotive force…

Astrophysics · Physics 2008-11-26 I. Rogachevskii , N. Kleeorin

We investigate shear-induced crystallization in a very dense flow of mono-disperse inelastic hard spheres. We consider a steady plane Couette flow under constant pressure and neglect gravity. We assume that the granular density is greater…

Soft Condensed Matter · Physics 2009-11-11 Evgeniy Khain , Baruch Meerson

Small steady-state deformational oscillations of a drop of a viscous magnetic liquid in a non-stationary uniform magnetic field are theoretically investigated for low Reynolds numbers. The drop is suspended in another viscous magnetic…

Fluid Dynamics · Physics 2022-06-22 Alexander N. Tyatyushkin

Turbulent mixing in the radiative regions of stars is usually either ignored or crudely accounted for in most stellar evolution models. However, there is growing theoretical and observational evidence that such mixing is present and can…

Solar and Stellar Astrophysics · Physics 2020-10-07 P. Garaud

We develop a new scaling theory for the resistive tearing mode instability of a current sheet with a strong shear flow across the layer. The growth rate decreases with increasing flow shear and is completely stabilized as the shear flow…

Plasma Physics · Physics 2026-01-14 Alfred Mallet , Stefan Eriksson , Marc Swisdak , James Juno

According to Rayleigh's criterion, rotating flows are linearly stable when their specific angular momentum increases radially outward. The celebrated magnetorotational instability opens a way to destabilize those flows, as long as the…

Fluid Dynamics · Physics 2015-11-23 Frank Stefani , Oleg N. Kirillov

The effect of small-amplitude periodic shear on annealing of a shear band in binary glasses is investigated using molecular dynamics simulations. The shear band is first introduced in stable glasses via large-amplitude periodic shear, and…

Soft Condensed Matter · Physics 2021-05-11 Nikolai V. Priezjev

We investigate the effect of shear viscosity and Ohmic resistivity on the magnetorotational instability (MRI) in vertically stratified accretion disks through a series of local simulations with the Athena code. First, we use a series of…

High Energy Astrophysical Phenomena · Physics 2015-05-20 Jacob B. Simon , John F. Hawley , Kris Beckwith

A quasi-linear theory is presented for how randomly forced, barotropic velocity fluctuations cause an exponentially-growing, large-scale (mean) magnetic dynamo in the presence of a uniform shear flow, $\vec{U} = S x \vec{e}_y$. It is a…

Astrophysics of Galaxies · Physics 2015-05-30 James C. McWilliams

We investigate the density-shear instability in Hall-MHD via numerical simulation of the full non-linear problem, in the context of magnetar activity. We confirm the development of the instability of a plane-parallel magnetic field with an…

High Energy Astrophysical Phenomena · Physics 2015-09-03 Konstantinos N. Gourgouliatos , Todor Kondic , Maxim Lyutikov , Rainer Hollerbach