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Related papers: Fast dynamos in spherical boundary-driven flows

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Precession has been proposed as an alternative power source for planetary dynamos. Previous hydrodynamic simulations suggested that precession can generate very complex flows in planetary liquid cores [Y. Lin, P. Marti, and J. Noir,…

Fluid Dynamics · Physics 2016-07-27 Yufeng Lin , Philippe Marti , Jerome Noir , Andrew Jackson

The Derviche Tourneur Sodium experiment, a spherical Couette magnetohydrodynamics experiment with liquid sodium as the medium and a dipole magnetic field imposed from the inner sphere, recently underwent upgrades to its diagnostics to…

Fluid Dynamics · Physics 2018-04-18 Elliot Kaplan , Henri-Claude Nataf , Nathanaël Schaeffer

We consider a flow of heat conducting fluid inside a moving domain whose shape in time is prescribed. The flow in this case is governed by the Navier-Stokes-Fourier system consisting of equation of continuity, momentum balance, entropy…

Analysis of PDEs · Mathematics 2017-11-29 Ondrej Kreml , Vaclav Macha , Sarka Necasova , Aneta Wroblewska-Kaminska

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…

Fluid Dynamics · Physics 2018-03-12 F. Stefani , A. Gailitis , G. Gerbeth , A. Giesecke. Th. Gundrum , G. Ruediger , M. Seilmayer , T. Vogt

To understand the dynamo driven by time-dependent flow, e.g. turbulence, we investigate numerically the dynamo induced by time-periodic force in rotating magnetohydrodynamic flow and focus on the effect of force frequency on the dynamo…

Fluid Dynamics · Physics 2018-03-14 Xing Wei

Recently Shukurov et al [Phys Rev E 72, 025302 (2008)], made use of non-orthogonal curvilinear coordinate system on a dynamo Moebius strip flow, to investigate the effect of stretching by a turbulent liquid sodium flow. In plasma physics,…

Mathematical Physics · Physics 2009-06-22 Garcia de Andrade

The "reverse-dynamo" mechanism - the amplification/generation of fast plasma flows by micro scale (turbulent) magnetic fields via magneto-fluid coupling is recognized and explored. It is shown that macro-scale magnetic fields and flows are…

The self-excitation of magnetic field by a spiral Couette flow between two coaxial cylinders is considered. We solve numerically the fully nonlinear, three-dimensional MHD equations for magnetic Prandtl numbers Pm (ratio of kinematic…

Astrophysics · Physics 2009-11-06 Wolfgang Dobler , Anvar Shukurov , Axel Brandenburg

We consider the Navier-Stokes-Fourier-Poisson system driven by an inhomogeneous temperature distribution on the boundary of an exterior fluid domain. We impose the finite mass constraint, positive far field condition for the temperature as…

Analysis of PDEs · Mathematics 2024-05-14 Nilasis Chaudhuri , Eduard Feireisl , Ewelina Zatorska , Boguslaw Zegarlinski

We consider incompressible flows between two transversely vibrating solid walls and construct an asymptotic expansion of solutions of the Navier-Stokes equations in the limit when both the amplitude of vibrations and the thickness of the…

Fluid Dynamics · Physics 2011-08-16 Konstantin Ilin , Andrey Morgulis

We perform experiments on an active chiral fluid system of self-spinning rotors in confining boundary. Along the boundary, actively rotating rotors collectively drives a unidirectional material flow. We systematically vary rotor density and…

Soft Condensed Matter · Physics 2020-02-19 Xiang Yang , Chenyang Ren , Kangjun Cheng , H. P. Zhang

We consider rotating, kinematic dynamos at low magnetic Prandtl number $Pm$. We show that the inclusion of rotation leads to an increase in spatio-temporal coherence and a modification of the turbulent spectrum. These effects make the flow…

Fluid Dynamics · Physics 2018-11-06 Vassilios Dallas , Steve Tobias

We consider the free boundary problem for relativistic plasma--vacuum interfaces in two and three spatial dimensions. The plasma flow is governed by the equations of ideal relativistic magnetohydrodynamics, while the vacuum magnetic and…

Analysis of PDEs · Mathematics 2026-04-30 Paolo Secchi , Yuri Trakhinin , Tao Wang

We consider the Navier--Stokes equations for compressible heat-conducting ideal polytropic gases in a bounded annular domain when the viscosity and thermal conductivity coefficients are general smooth functions of temperature. A…

Analysis of PDEs · Mathematics 2020-09-24 Ling Wan , Tao Wang

The flow of an electrically conducting fluid driven by a traveling magnetic field imposed at the endcaps of a cylindrical annulus is numerically studied. At sufficiently large magnetic Reynolds number, the system undergoes a transition from…

Fluid Dynamics · Physics 2018-06-27 Sandeep R. Kanuganti , Stephan Fauve , Christophe Gissinger

Within the framework of a two-fluid description possible pathways for the generation of fast flows (dynamical as well as steady) in the lower solar atmosphere is established. It is shown that a primary plasma flow (locally sub-Alfv\'enic)…

We theoretically and experimentally investigate the flow field that emerges from a rod-like microrotor rotating about its center in a non-axisymmetric manner. A simple theoretical model is proposed that uses a superposition of two rotlets…

Fluid Dynamics · Physics 2016-02-24 Jannis Köhler , Jan Friedrich , Andreas Ostendorf , Evgeny Gurevich

Dynamo action in planetary cores has been extensively studied in the context of convectively-driven flows. We show in this letter that mechanical forcings, namely tides, libration and precession, are also able to kinematically sustain a…

Fluid Dynamics · Physics 2018-11-07 K. Sandeep Reddy , Benjamin Favier , Michael Le Bars

For cylindrical differentially rotating plasmas, we study large-scale magnetic field generation from finite amplitude non-axisymmetric perturbations by comparing numerical simulations with quasi-linear analytic theory. When initiated with a…

High Energy Astrophysical Phenomena · Physics 2016-10-31 F. Ebrahimi , E. G. Blackman

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