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Related papers: Numerical Simulations of Kinematic Dynamo Action

200 papers

Fluctuation dynamo action has been obtained for a flow previously used to model fluid turbulence, where the sensitivity of the magnetic field parameters to the kinetic energy spectrum can be explored. We apply quantitative morphology…

Astrophysics · Physics 2008-11-26 S. Louise Wilkin , Carlo F. Barenghi , Anvar Shukurov

In this paper we address a discrepancy between the surface flux evolution in a 3D kinematic dynamo model and a 2D surface flux transport model that has been closely calibrated to the real Sun. We demonstrate that the difference is due to…

Solar and Stellar Astrophysics · Physics 2019-07-24 T. Whitbread , A. R. Yeates , A. Muñoz-Jaramillo

We review our current understanding of galactic dynamo theory, paying particular attention to numerical simulations both of the mean-field equations and the original three-dimensional equations relevant to describing the magnetic field…

Astrophysics of Galaxies · Physics 2014-12-12 Axel Brandenburg

Stellar dynamos are driven by complex couplings between rotation and turbulent convection, which drive global-scale flows and build and rebuild stellar magnetic fields. When stars like our sun are young, they rotate much more rapidly than…

The possibility of non-helical large scale dynamo action is investigated using three-dimensional simulations of global accretion discs as well as idealized local simulations without rotation and only shear. Particular emphasis is placed on…

Astrophysics · Physics 2009-11-06 R. Arlt , A. Brandenburg

It is shown, that the saturated $\alpha$-effect taken from the nonlinear dynamo equations for the thin disk can still produce exponentially growing magnetic field in the case, when this field does not feed back on the $\alpha$. For negative…

Fluid Dynamics · Physics 2015-05-18 M. Reshetnyak

We perform direct numerical simulations of forced and freely decaying 3D magnetohydrodynamic turbulence in order to model magnetic field evolution during cosmological phase transitions in the early Universe. Our approach assumes the…

Cosmology and Nongalactic Astrophysics · Physics 2010-11-30 Tina Kahniashvili , Axel Brandenburg , Alexander G. Tevzadze , Bharat Ratra

We numerically investigate the efficiency of a spherical Couette flow at generating a self-sustained magnetic field. No dynamo action occurs for axisymmetric flow while we always found a dynamo when non-axisymmetric hydrodynamical…

Geophysics · Physics 2020-07-17 Céline Guervilly , Philippe Cardin

Active processes drive and guide biological dynamics across scales -- from subcellular cytoskeletal remodelling, through tissue development in embryogenesis, to population-level bacterial colonies expansion. In each of these, biological…

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

We report the first experimental observation of reversals of a dynamo field generated in a laboratory experiment based on a turbulent flow of liquid sodium. The magnetic field randomly switches between two symmetric solutions B and -B. We…

Using the non-linear mean-field dynamo models we calculate the magnetic cycle parameters, like the dynamo cycle period, the amplitude of the total magnetic energy, and the Poynting flux luminosity from the surface for the solar analogs with…

Solar and Stellar Astrophysics · Physics 2021-01-27 V. V. Pipin

We present the results of 3--D nonlinear simulations of magnetic dynamo action by core convection within A-type stars of 2 solar masses, at a range of rotation rates. We consider the inner 30% by radius of such stars, with the spherical…

Astrophysics · Physics 2009-11-10 Matthew Browning , Allan Sacha Brun , Juri Toomre

Hydromagnetic dynamo theory provides the prevailing theoretical description for the origin of magnetic fields in the universe. Here we consider the problem of kinematic, small-scale dynamo action driven by a random, incompressible,…

Plasma Physics · Physics 2011-03-10 Joanne Mason , Leonid Malyshkin , Stanislav Boldyrev , Fausto Cattaneo

We investigate numerically the kinematic dynamo induced by the superposition of two helical waves in a periodic box as a simplified model to understand the dynamo action in astronomical bodies. The effects of magnetic Reynolds number,…

Fluid Dynamics · Physics 2015-06-03 Xing Wei

Hydrodynamic and magnetohydrodynamic numerical studies of a mechanically forced two-vortex flow inside a sphere are reported. The simulations are performed in the intermediate regime between the laminar flow and developed turbulence where a…

Fluid Dynamics · Physics 2015-05-14 K. Reuter , F. Jenko , A. Tilgner , C. B. Forest

Magnetic fields of low-mass stars and planets are thought to originate from self-excited dynamo action in their convective interiors. Observations reveal a variety of field topologies ranging from large-scale, axial dipole to more…

Solar and Stellar Astrophysics · Physics 2015-06-04 Martin Schrinner , Ludovic Petitdemange , Emmanuel Dormy

Kinetic instabilities are one of the most challenging aspects in computational plasma physics. Accurately capturing their onset and evolution requires fine resolution of the high-dimensional distribution functions of each relevant species,…

Plasma Physics · Physics 2025-11-05 Rostislav-Paul Wilhelm , Manuel Torrilhon

To enhance the understanding of the behavior of active nematic, it is important to understand the behavior of topological defects. In this paper, we study the configuration of topological defects of a two-dimensional active nematic around a…

Soft Condensed Matter · Physics 2026-02-16 Hiroki Matsukiyo , Jun-ichi Fukuda

Several recent advances in turbulent dynamo theory are reviewed. High resolution simulations of small-scale and large-scale dynamo action in periodic domains are compared with each other and contrasted with similar results at low magnetic…

Solar and Stellar Astrophysics · Physics 2012-07-10 Axel Brandenburg , Dmitry Sokoloff , Kandaswamy Subramanian