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Related papers: The Unsteady Taylor--Vortex Dynamo is Fast

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In this paper, we investigate the Rayleigh-Taylor instability problem for two compressible, immiscible, inviscid flows rotating with an constant angular velocity, and evolving with a free interface in the presence of a uniform gravitational…

General Mathematics · Mathematics 2012-05-01 Ran Duan , Fei Jiang , Song Jiang

Large-scale planetary or stellar magnetic fields generated by a dynamo effect are mostly attributed to flows forced by buoyancy forces in electrically conducting fluid layers. However, these large-scale fields may also be controlled by…

Solar and Stellar Astrophysics · Physics 2015-06-22 David Cébron , Rainer Hollerbach

Magnetic fields of planets, stars and galaxies are generated by self-excitation in moving electrically conducting fluids. Once produced, magnetic fields can play an active role in cosmic structure formation by destabilizing rotational flows…

Plasma Physics · Physics 2016-10-19 F. Stefani , M. Gellert , Ch. Kasprzyk , A. Paredes , G. Ruediger , M. Seilmayer

A rigorous theory for the generation of a large-scale magnetic field by random non-helically forced motions of a conducting fluid combined with a linear shear is presented in the analytically tractable limit of low Rm and weak shear. The…

Astrophysics · Physics 2011-12-15 T. Heinemann , J. C. McWilliams , A. A. Schekochihin

The main objective of this article is to study both dynamic and structural transitions of the Taylor-Couette flow, using the dynamic transition theory and geometric theory of incompressible flows developed recently by the authors. In…

Mathematical Physics · Physics 2010-05-13 Tian Ma , Shouhong Wang

Rayleigh-Taylor (RT) instabilities are prevalent in many physical regimes ranging from astrophysical to laboratory plasmas and have primarily been studied using fluid models, the majority of which have been ideal fluid models. This work is…

Plasma Physics · Physics 2022-07-13 John Rodman , Petr Cagas , Ammar Hakim , Bhuvana Srinivasan

The large Reynolds number asymptotic approximation of the neutral curve of Taylor-Couette flow subject to axial uniform magnetic field is analysed. The flow has been extensively studied since early 90's as the magneto-rotational instability…

Fluid Dynamics · Physics 2019-02-27 Kengo Deguchi

We consider the linear stability of dissipative MHD Taylor-Couette flow with imposed toroidal magnetic fields. The inner and outer cylinders can be either insulating or conducting; the inner one rotates, the outer one is stationary. The…

Astrophysics · Physics 2009-11-11 G. Ruediger , M. Schultz , D. Shalybkov , R. Hollerbach

We study the dynamo instability for a Kazantsev-Kraichnan flow with three velocity components that depends only on two-dimensions u = (u(x, y, t), v(x, y, t), w(x, y, t)) often referred to as 2.5 dimensional (2.5D) flow. Within the…

Fluid Dynamics · Physics 2016-11-03 K. Seshasayanan , A. Alexakis

The evolution of a Taylor-Green forced magnetohydrodynamic (MHD) system showing dynamo activity is analyzed via direct numerical simulations. The statistical properties of the velocity and magnetic field in Eulerian coordinates and along…

Fluid Dynamics · Physics 2015-06-17 Holger Homann , Yannick Ponty , Giorgio Krstulovic , Rainer Grauer

The Rayleigh-Taylor instability is a key process in many fields of Physics ranging from astrophysics to inertial confinement fusion. It is usually analyzed deriving the linearized fluid equations, but the physics behind the instability is…

High Energy Astrophysical Phenomena · Physics 2015-05-27 A Bret

Turbulence is one of the most fascinating phenomena in nature and one of the biggest challenges for modern physics. It is common knowledge that a flow of a simple, Newtonian fluid is likely to be turbulent, when velocity is high, viscosity…

Chaotic Dynamics · Physics 2017-05-10 Alexander Groisman , Victor Steinberg

In this paper, we find a new large scale instability displayed by a rotating flow in forced turbulence. The turbulence is generated by a small scale external force at low Reynolds number. The theory is built on the rigorous asymptotic…

Fluid Dynamics · Physics 2015-04-28 M. I. Kopp , A. V. Tur , V. V. Yanovsky

It is numerically demonstrated by means of a magnetohydrodynamics code that a short Taylor-Couette setup with a body force can sustain dynamo action. The magnetic threshold is comparable to what is usually obtained in spherical geometries.…

Numerical Analysis · Mathematics 2015-06-04 C. Nore , J. -L. Guermond , R. Laguerre , J. Leorat , F. Luddens

Warped astrophysical discs are usually treated as laminar viscous flows, which have anomalous properties when the disc is nearly Keplerian and the viscosity is small: fast horizontal shearing motions and large torques are generated, which…

Solar and Stellar Astrophysics · Physics 2015-06-15 Gordon I. Ogilvie , Henrik N. Latter

The magnetohydrodynamic stability of axially unbounded cylindrical flows is considered which contain a toroidal magnetic background field with the same radial profile as the linear azimuthal velocity. Chandrasekhar (1956) has shown for…

Astrophysics of Galaxies · Physics 2015-09-30 Guenther Ruediger , Manfred Schultz , Frank Stefani , Michael Mond

We numerically calculate the growth and saturation of the Rayleigh-Taylor instability caused by the deceleration of relativistic outflows with Lorentz factor {\Gamma} = 10, 30, and 100. The instability generates turbulence whose scale…

High Energy Astrophysical Phenomena · Physics 2015-06-15 Paul C. Duffell , Andrew I. MacFadyen

We present a three--pronged numerical approach to the dynamo problem at low magnetic Prandtl numbers $P_M$. The difficulty of resolving a large range of scales is circumvented by combining Direct Numerical Simulations, a Lagrangian-averaged…

Geophysics · Physics 2009-11-10 Y. Ponty , P. D. Mininni , D. C. Montgomery , J. -F. Pinton , H. Politano , A. Pouquet

Decades ago S. Lundquist, S. Chandrasekhar, P.H. Roberts and R. J.~Tayler first posed questions about the stability of Taylor-Couette flows of conducting material under the influence of large-scale magnetic fields. These and many new…

Plasma Physics · Physics 2018-05-23 Günther Rüdiger , Marcus Gellert , Rainer Hollerbach , Manfred Schultz , Frank Stefani

We study the linear stability of weakly magnetized differentially rotating plasmas in both collisionless kinetic theory and Braginskii's theory of collisional, magnetized plasmas. We focus on the very weakly magnetized limit that is…

Astrophysics of Galaxies · Physics 2015-06-23 Eliot Quataert , Tobias Heinemann , Anatoly Spitkovsky
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