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Related papers: The Nonlinear Turbulent Dynamo

200 papers

We investigate hydromagnetic turbulence of primordial magnetic fields using magnetohydrodynamics (MHD) in an expanding universe. We present the basic, covariant MHD equations, find solutions for MHD waves in the early universe, and…

Astrophysics · Physics 2014-10-13 Axel Brandenburg , Kari Enqvist , Poul Olesen

Turbulence in a conducting plasma can amplify seed magnetic fields in what is known as the turbulent, or small-scale, dynamo. The associated growth rate and emergent magnetic-field geometry depend sensitively on the material properties of…

High Energy Astrophysical Phenomena · Physics 2022-10-17 Alisa K. Galishnikova , Matthew W. Kunz , Alexander A. Schekochihin

We perform numerical simulation of dynamo with magnetic Prandtl number $\mathrm{Pm} =0.2$ on $1024^3$ grid, and compute the energy fluxes and the shell-to-shell energy transfers. These computations indicate that the magnetic energy growth…

Fluid Dynamics · Physics 2015-06-26 Rohit Kumar , Mahendra K. Verma , Ravi Samtaney

A three-dimensional numerical computation of magnetohydrodynamic dynamo behavior is described. The dynamo is mechanically forced with a driving term of the Taylor-Green type. The magnetic field development is followed from negligibly small…

Astrophysics · Physics 2007-05-23 P. D. Mininni , Y. Ponty , D. C. Montgomery , J. -F. Pinton , H. Politano , A. Pouquet

The energy distribution is a fundamental property of magnetohydrodynamic (MHD) turbulence. In strongly magnetized turbulence energy imbalances can arise, quantified by the so-called residual energy: $E_r~=~(E_{kin}~ - ~E_{mag})$; $E_{kin}$…

Solar and Stellar Astrophysics · Physics 2025-12-16 R. Skalidis , A. Tritsis , J. R. Beattie , P. F. Hopkins

We consider a natural generalization of the Kazantsev-Kraichnan model for small-scale turbulent dynamo. This generalization takes account of statistical time asymmetry of a turbulent flow, and, thus, allows to describe velocity fields with…

Fluid Dynamics · Physics 2023-10-26 A. V. Kopyev , A. M. Kiselev , A. S. Il'yn , V. A. Sirota , K. P. Zybin

We present high resolution 2D and 3D simulations of magnetized decaying turbulence in relativistic resistive magneto-hydrodynamics. The simulations show dynamic formation of large scale intermittent long-lived current sheets being disrupted…

High Energy Astrophysical Phenomena · Physics 2021-12-22 Alexander Chernoglazov , Bart Ripperda , Alexander A. Philippov

We study the Lagrangian mechanism of the fluctuation dynamo at zero Prandtl number and infinite magnetic Reynolds number, in the Kazantsev-Kraichnan model of white-noise advection. With a rough velocity field corresponding to a turbulent…

Plasma Physics · Physics 2011-03-07 Gregory L. Eyink

We analyze the magnetic field evolution in dense quark matter with unbroken chiral symmetry, which can be found inside quark and hybrid stars. The magnetic field evolves owing to the chiral magnetic effect in the presence of the electroweak…

High Energy Astrophysical Phenomena · Physics 2018-11-28 Maxim Dvornikov

We develop an analytical model to follow the cosmological evolution of magnetic fields in disk galaxies. Our assumption is that fields are amplified from a small seed field via magnetohydrodynamical (MHD) turbulence. We further assume that…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-18 Stanislav Shabala , James M. G. Mead , Paul Alexander

Magnetic fields are critical at many scales to galactic dynamics and structure, including multiphase pressure balance, dust processing, and star formation. Dynamo action determines their dynamical structure and strength. Simulations of…

Astrophysics of Galaxies · Physics 2026-02-17 Frederick A. Gent , Mordecai-Mark Mac Low , Maarit J. Korpi-Lagg , Touko Puro , Matthias Reinhardt

Electron plasmas confined by an external magnetic field exhibit variations in a two-dimensional plane orthogonal to the confining magnetic field. A nonlinear fluid simulation code to investigate the properties of 2-D electron plasma wave…

Plasma Physics · Physics 2009-11-13 Dastgeer Shaikh , P. K. Shukla

The strength and structure of the large-scale magnetic field in protoplanetary discs are still unknown, although they could have important consequences for the dynamics and evolution of the disc. Using a mean-field approach in which we…

Earth and Planetary Astrophysics · Physics 2015-06-19 Jerome Guilet , Gordon I. Ogilvie

The nature and origin of turbulence and magnetic fields in the intergalactic space are important problems that are yet to be understood. We propose a scenario in which turbulent flow motions are induced via the cascade of the vorticity…

Astrophysics · Physics 2009-11-13 Dongsu Ryu , Hyesung Kang , Jungyeon Cho , Santabrata Das

The shape and the dynamics of reversals of the magnetic field in a turbulent dynamo experiment are investigated. We report the evolution of the dipolar and the quadrupolar parts of the magnetic field in the VKS experiment, and show that the…

Fluid Dynamics · Physics 2015-05-20 Christophe Gissinger

It has been recently shown numerically that there exists an inverse transfer of magnetic energy in decaying, nonhelical, magnetically dominated, magnetohydrodynamic turbulence in 3-dimensions (3D). We suggest that magnetic reconnection is…

Cosmology and Nongalactic Astrophysics · Physics 2020-12-23 Pallavi Bhat , Muni Zhou , Nuno F. Loureiro

We study the evolution of an inflation-generated magnetic field, due to its coupling to fluid motions, during cosmological phase transitions. We find that the magnetic field stays almost unchanged on large scales, while on small scales the…

Cosmology and Nongalactic Astrophysics · Physics 2013-05-30 Tina Kahniashvili , Axel Brandenburg , Leonardo Campanelli , Bharat Ratra , Alexander G. Tevzadze

The magnetic Prandtl number Pr_M is the ratio of viscosity to resistivity. In astrophysical disks the diffusion of angular momentum (viscosity) and magnetic fields (resistivity) are controlled by turbulence. Phenomenological models of the…

High Energy Astrophysical Phenomena · Physics 2010-01-15 Xiaoyue Guan , Charles F. Gammie

We present an attempt to reach realistic turbulent regime in direct numerical simulations of the geodynamo. We rely on a sequence of three convection-driven simulations in a rapidly rotating spherical shell. The most extreme case reaches…

Direct numerical simulations of decaying and forced magnetohydrodynamic (MHD) turbulence without and with mean magnetic field are analyzed by higher-order two-point statistics. The turbulence exhibits statistical anisotropy with respect to…

Plasma Physics · Physics 2009-11-10 Wolf-Christian Mueller , Dieter Biskamp , Roland Grappin