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Related papers: Nonlinear Turbulent Magnetic Diffusion and Mean-Fi…

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A plane-shear flow in a fluid with forced turbulence is considered. If the fluid is electrically-conducting then a mean electromotive force (EMF) results even without basic rotation and the magnetic diffusivity becomes a highly anisotropic…

Astrophysics · Physics 2009-11-11 G. Ruediger , L. L. Kitchatinov

It is often asserted or implicitly assumed, without justification, that the results of two-dimensional investigations of plasma turbulence are applicable to the three-dimensional plasma environments of interest. A projection method is…

Solar and Stellar Astrophysics · Physics 2019-02-20 Gregory G. Howes

Nonlinearity of magneto-dynamics is typically described by a single constant, $\mathcal{N}$, with positive and negative values indicating repulsion and attraction of magnons, respectively. In thin magnetic films with easy-plane magnetic…

Mesoscale and Nanoscale Physics · Physics 2018-04-06 Mykola Dvornik , Johan Åkerman

A dynamical approach, rather than the usual statistical approach, is taken to explore the physical mechanisms underlying the nonlinear transfer of energy, the damping of the turbulent fluctuations, and the development of coherent structures…

Solar and Stellar Astrophysics · Physics 2015-08-19 G. G. Howes

Energetic particle transport in a finite amplitude magnetosonic and Alfvenic turbulence is considered using Monte Carlo particle simulations, which involve an integration of particle equation of motion. We show that in a low-Betha plasma…

Astrophysics · Physics 2008-02-03 G. Michalek , M. Ostrowski , R. Schlickeiser

We have derived the full set of MHD equations for incompressible shear flow of a magnetized fluid and considered their solution in the wave-vector space. The linearized equations give the famous amplification of slow magnetosonic waves and…

Plasma Physics · Physics 2015-05-27 Z. D. Dimitrov , Y. G. Maneva , T. S. Hristov , T. M. Mishonov

The problem of cosmic-ray scattering in the turbulent electromagnetic fields of the interstellar medium and the solar wind is of great importance due to the variety of applications of the resulting diffusion coefficients. Examples are…

High Energy Astrophysical Phenomena · Physics 2015-05-20 R. C. Tautz

We investigate the magnetic field which is generated by turbulent motions of a weakly ionized gas. Galactic molecular clouds give us an example of such a medium. As in the Kazantsev-Kraichnan model we assume a medium to be homogeneous and a…

Astrophysics of Galaxies · Physics 2013-09-25 Ya. N. Istomin , A. M. Kiselev

We use the mean-field dynamo equations to show that an incoherent alpha effect in mirror-symmetric turbulence in a shearing flow can generate a large scale, coherent magnetic field. We illustrate this effect with simulations of a few simple…

Astrophysics · Physics 2015-06-24 Ethan T. Vishniac , Axel Brandenburg

We present numerical simulations and explore scalings and anisotropy of compressible magnetohydrodynamic (MHD) turbulence. Our study covers both gas pressure dominated (high beta) and magnetically dominated (low beta) plasmas at different…

Astrophysics · Physics 2011-05-05 Jungyeon Cho , A. Lazarian

The nonlinear dynamo effect of tearing modes is derived with the resistive MHD equations. The dynamo effect is divided into two parts, parallel and perpendicular to the magnetic field. Firstly, the force-free plasma is considered. It is…

Plasma Physics · Physics 2021-01-12 Luo Yuhang , Gao Zhe

When restricted to magnetic flux tubes, the gyrokinetic theory of microturbulence gives the same radial transport for ions and electrons. But, exact magnetic surfaces do not exist in the presence of what is called electrostatic…

Plasma Physics · Physics 2026-05-12 Allen H Boozer

Non-ideal fluids are generally subject to the occurrence of non-isotropic pressure tensors, whose determination is fundamental in order to characterize their dynamical and thermodynamical properties. This requires the implementation of…

Plasma Physics · Physics 2023-06-22 Claudio Cremaschini , Jiří Kovář , Zdeněk Stuchlík , Massimo Tessarotto

Observations and modelling suggest that the fluctuations in magnetised plasmas exhibit scale-dependent anisotropy, with more energy in the fluctuations perpendicular to the mean magnetic field than in the parallel fluctuations and the…

Solar and Stellar Astrophysics · Physics 2013-04-22 T. Laitinen , S. Dalla , J. Kelly , M. Marsh

We find and investigate via numerical simulations self-sustained two-dimensional turbulence in a magnetohydrodynamic flow with a maximally simple configuration: plane, noninflectional (with a constant shear of velocity) and threaded by a…

Plasma Physics · Physics 2014-10-01 G. R. Mamatsashvili , D. Z. Gogichaishvili , G. D. Chagelishvili , W. Horton

The effects of resonant magnetic perturbations on the turbulent transport of fast ions in tokamak devices are investigated using a theoretical transport model of test-particle type. The direct numerical simulation method is used to compute,…

Plasma Physics · Physics 2024-06-19 D. I. Palade

We introduce a Monte Carlo model of nonlinear diffusive shock acceleration allowing for the generation of large-amplitude magnetic turbulence. The model is the first to include strong wave generation, efficient particle acceleration to…

Astrophysics · Physics 2008-11-26 Andrey Vladimirov , Donald C. Ellison , Andrei Bykov

Isotropic homogeneous hydromagnetic turbulence is studied using numerical simulations at resolutions of up to 1024^3 meshpoints. It is argued that, in contrast to the kinematic regime, the nonlinear regime is characterized by a spectral…

Astrophysics · Physics 2007-05-23 A. Brandenburg , N. E. L. Haugen , W. Dobler

Numerical simulations of the 3D MHD-equations that describe rotating magnetoconvection in a Cartesian box have been performed using the code NIRVANA. The characteristics of averaged quantities like the turbulence intensity and the turbulent…

Earth and Planetary Astrophysics · Physics 2015-03-13 A. Giesecke

We use a set of magnetohydrodynamics (MHD) simulations of fully-developed (driven) turbulence to study the anisotropy in the velocity field that is induced by the presence of the magnetic field. In our models we study turbulence…

Astrophysics of Galaxies · Physics 2015-05-30 Alejandro Esquivel , Alex Lazarian