English
Related papers

Related papers: Kinematic dynamo in spherical Couette flow

200 papers

Recent numerical simulations of dynamo action resulting from rotating convection have revealed some serious problems in applying the standard picture of mean field electrodynamics at high values of the magnetic Reynolds number, and have…

Solar and Stellar Astrophysics · Physics 2013-02-20 D. W. Hughes , M. R. E. Proctor

Direct numerical simulations of a liquid metal filling the gap between two concentric spheres are presented. The flow is governed by the interplay between the rotation of the inner sphere (measured by the Reynolds number Re) and a weak…

Fluid Dynamics · Physics 2023-07-26 Ferran Garcia , Martin Seilmayer , André Giesecke , Frank Stefani

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

The VKS experiment has evidenced dynamo action in a highly turbulent liquid sodium von K\'arm\'an flow [R. Monchaux et al., Phys. Rev. Lett. {\bf 98}, 044502 (2007)]. However, the existence and the onset of a dynamo happen to depend on the…

Fluid Dynamics · Physics 2011-06-10 A. Pinter , B. Dubrulle , F. Daviaud , J. Leorat

Late-type stars rotate differentially owing to anisotropic turbulence in their outer convection zones. The rotation is called solar-like (SL) when the equator rotates fastest and anti-solar (AS) otherwise. Hydrodynamic simulations show a…

Solar and Stellar Astrophysics · Physics 2015-03-25 Bidya Binay Karak , Petri J. Kapyla , Maarit J. Kapyla , Axel Brandenburg , N. Olspert , J. Pelt

We examine how perturbed shear flows evolve in two-dimensional, incompressible, inviscid hydrodynamical fluids, with the ultimate goal of understanding the dynamics of accretion disks. To linear order, vorticity waves are swung around by…

Astrophysics · Physics 2009-11-13 Yoram Lithwick

Recently Vishik anti-fast dynamo theorem, has been tested against non-stretching flux tubes [Phys Plasmas 15 (2008)]. In this paper, another anti-dynamo theorem, called Cowling's theorem, which states that axisymmetric magnetic fields…

Mathematical Physics · Physics 2010-03-15 L. C. Garcia de Andrade

We provide a minimal model for an active nematic film in contact with both a solid substrate and a passive isotropic fluid, and explore its dynamics in one and two dimensions using a combination of hybrid Lattice Boltzmann simulations and…

Soft Condensed Matter · Physics 2017-02-16 Matthew L. Blow , Marco Aqil , Benno Liebchen , Davide Marenduzzo

Choosing a simple class of flows, with characteristics that may be present in the Earth's core, we study the ability to generate a magnetic field when the flow is permitted to oscillate periodically in time. The flow characteristics are…

Geophysics · Physics 2009-11-10 Ashley P. Willis , David Gubbins

By incorporating a large-scale shear flow into turbulent rotating convection, we show that a sufficiently strong shear can promote dynamo action in flows that in the absence of shear do not act as dynamos. Our results are consistent with a…

Astrophysics · Physics 2009-02-04 David W. Hughes , Michael R. E. Proctor

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

The dynamics of stably stratified stellar radiative zones is of considerable interest due to the availability of increasingly detailed observations of Solar and stellar interiors. This article reports the first non-axisymmetric and…

Fluid Dynamics · Physics 2021-05-13 Radostin D. Simitev , Friedrich H. Busse

We have performed numerical simulations of the kinematic induction equation in order to examine the dynamo efficiency of an axisymmetric von-K\'arm\'an-like flow subject to time-dependent non-axisymmetric velocity perturbations. The…

Fluid Dynamics · Physics 2015-06-11 Andre Giesecke , Frank Stefani , Javier Burguete

This paper addresses the stability of plane Couette flow in the presence of strong density and viscosity stratifications. It demonstrates the existence of a generalised inflection point that satisfies the generalised Fjortoft's criterion of…

Fluid Dynamics · Physics 2024-06-13 B. Bugeat , P. C. Boldini , A. M. Hasan , R. Pecnik

This study focuses on the modeling and dynamics of gravity-driven, axisymmetric thin liquid film flow along a conical surface. Spatial linear stability analysis is performed on the basis of a Benney-type equation derived for the present…

Fluid Dynamics · Physics 2026-02-11 Longmin Tang , Guangzhao Zhou

This paper introduces a simulation study of fluid actuated multi-driven closed system as spherical mobile robot called "RollRoller". Robot's mechanism design consists of two essential parts: tubes to lead a core and mechanical controlling…

Robotics · Computer Science 2016-10-21 Seyed Amir Tafrishi , Sandor M. Veres , Esmaeil Esmaeilzadeh , Mikhail Svinin

For the understanding of planetary and stellar dynamos an overview of the major parameter dependences of convection driven dynamos in rotating spherical fluid shells is desirable. Although the computationally accessible parameter space is…

Fluid Dynamics · Physics 2009-04-29 F. H. Busse , R. D. Simitev

The wavefunction coefficients of conformally coupled scalars in power-law FRW cosmologies satisfy differential equations governed by a set of simple combinatorial rules known as the kinematic flow. In this paper we derive the kinematic…

High Energy Physics - Theory · Physics 2025-08-18 Ross Glew , Andrzej Pokraka

We reveal and analyze an efficient magnetic dynamo action due to precession-driven hydrodynamic turbulence in the local model of a precessional flow, focusing on the kinematic stage of this dynamo. The growth rate of magnetic field…

Fluid Dynamics · Physics 2024-05-08 V. Kumar , F. Pizzi , G. Mamatsashvili , A. Giesecke , F. Stefani , A. J. Barker

The spherical Couette system consists of two differentially rotating concentric spheres with a fluid filled in between. We study a regime where the outer sphere is rotating rapidly enough so that the Coriolis force is important and the…

Fluid Dynamics · Physics 2024-12-16 Ankit Barik , Santiago A. Triana , Michael Hoff , Johannes Wicht