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This article is focused on the dynamics of a rotating electrically conducting fluid in a turbulent state. As inside the Earth's core or in various industrial processes, a flow is altered by the presence of both background rotation and a…

Fluid Dynamics · Physics 2011-04-01 Benjamin F. N. Favier , Fabien S. Godeferd , Claude Cambon

We present results from two-dimensional numerical simulations of a supersonic turbulent flow in the plane of the galactic disk, incorporating shear, thresholded and discrete star formation (SF), self-gravity, rotation and magnetic fields. A…

Astrophysics · Physics 2009-10-28 T. Passot , E. Vazquez-Semadeni , A. Pouquet

We consider turbulence induced by an arbitrary forcing and derive turbulence amplitude and turbulent transport coefficients, first by using a quasi-linear theory and then by using a multi-scale renormalisation analysis. With an isotropic…

Astrophysics · Physics 2009-11-13 Nicolas Leprovost , Eun-Jin Kim

It is well-recognized that the presence of magnetic fields will lead to anisotropic energy cascade and dissipation of astrophysical turbulence. With the diffusion approximation and linear dissipation rates, we study the cascade and damping…

Solar and Stellar Astrophysics · Physics 2009-03-31 Yanwei Jiang , Siming Liu , Vahé Petrosian

Accretion disc turbulence along with its effect on large-scale magnetic fields plays an important role in understanding disc evolution in general, and the launching of astrophysical jets in particular. Motivated by enabling a comprehensive…

High Energy Astrophysical Phenomena · Physics 2022-04-06 Oliver Gressel , Martin E. Pessah

Accretion disks are likely threaded by external vertical magnetic flux, which enhances the level of turbulence via the magnetorotational instability (MRI). Using shearing-box simulations, we find that such external magnetic flux also…

High Energy Astrophysical Phenomena · Physics 2015-06-22 Xue-Ning Bai , James M. Stone

We present numerical simulations of driven magnetohydrodynamic (MHD) turbulence with weak/moderate imposed magnetic fields. The main goal is to clarify dynamics of magnetic field growth. We also investigate the effects of the imposed…

Astrophysics · Physics 2011-02-11 J. Cho , E. Vishniac , A. Beresnyak , A. Lazarian , D. Ryu

The turbulent diffusion tensor describing the evolution of the mean concentration of a passive scalar is investigated for non-helically forced turbulence in the presence of rotation or a magnetic field. With rotation, the Coriolis force…

Solar and Stellar Astrophysics · Physics 2009-05-09 Axel Brandenburg , Andreas Svedin , Geoffrey M. Vasil

The global development of magnetohydrodynamic turbulence in an accretion disk is studied within a simplified disk model that omits vertical stratification. Starting with a weak vertical seed field, a saturated state is obtained after a few…

Astrophysics · Physics 2009-10-30 Philip J. Armitage

An effect of rotation on a developed turbulent stratified convection is studied. Dependencies of the hydrodynamic helicity, the alpha-tensor and the effective drift velocity of the mean magnetic field on the rate of rotation and an…

Astrophysics · Physics 2009-11-07 N. Kleeorin , I. Rogachevskii

Roles of turbulence in the context of magnetic reconnection are investigated with special emphasis on the mutual interaction between flow (large-scale inhomogeneous structure) and turbulence. In order to evaluate the effective transport due…

Solar and Stellar Astrophysics · Physics 2015-05-28 Nobumitsu Yokoi , Masahiro Hoshino

The scale separation approximation, which is in the base of the solar mean field dynamo models, can be hardly justified both by observations and theoretical applications to astrophysical dynamos.{ The general expression for the mean…

Solar and Stellar Astrophysics · Physics 2023-05-17 V. V. Pipin

Magnetized turbulence is ubiquitous in many astrophysical and terrestrial plasmas but no universal theory exists. Even the detailed energy dynamics in magnetohydrodynamic (MHD) turbulence are still not well understood. We present a suite of…

Astrophysics of Galaxies · Physics 2023-02-06 Philipp Grete , Brian W. O'Shea , Kris Beckwith

Using test-particle simulations, we investigate the temporal dependence of the two-point velocity correlation function for charged particles scattering in a time-independent spatially fluctuating magnetic field derived from a…

High Energy Astrophysical Phenomena · Physics 2015-06-05 Federico Fraschetti , Joe Giacalone

Using direct numerical simulations, we verify that "flow IV" of Roberts (1972) exhibits dynamo action dominated by horizontally averaged large-scale magnetic field. With the test-field method we compute the turbulent magnetic diffusivity…

Solar and Stellar Astrophysics · Physics 2013-08-09 Ebru Devlen , Axel Brandenburg , Dhrubaditya Mitra

We use previously published high-resolution synchrotron polarization data to perform an angular dispersion analysis with the aim of charactering magnetized turbulence in M51. We first analyze three distinct regions (the center of the…

Astrophysics of Galaxies · Physics 2015-06-12 Martin Houde , Andrew Fletcher , Rainer Beck , Roger H. Hildebrand , John E. Vaillancourt , Jeroen M. Stil

In interstellar medium studies, separating ordered and random velocity or magnetic fields is essential for interpreting turbulence in both simulations and observations. We investigate how the choice of averaging scale affects the…

Astrophysics of Galaxies · Physics 2026-04-01 A. Konstantinou , E. Ntormousi , K. Tassis

We explore some consequences of the ``alpha model,'' also called the ``Lagrangian-averaged'' model, for two-dimensional incompressible magnetohydrodynamic (MHD) turbulence. This model is an extension of the smoothing procedure in fluid…

Fluid Dynamics · Physics 2009-11-10 P. D. Mininni , D. C. Montgomery , A. G. Pouquet

To understand magnetic diffusion, momentum transport, and mixing in the interior of the sun, we consider an idealized model of the tachocline, namely magnetohydrodynamics (MHD) turbulence on a $\beta$ plane subject to a large scale shear…

Astrophysics · Physics 2011-02-11 Nicolas Leprovost , Eun-Jin Kim

Turbulence with a large magnetic Reyonolds number, generically leads to rapidly growing magnetic noise over and above any mean field. We revisit the dynamics of this fluctuating field, in homogeneous, isotropic, helical turbulence. Assuming…

Astrophysics · Physics 2007-05-23 K. Subramanian