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Related papers: Transport coefficients for the shear dynamo proble…

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Using numerical simulations at moderate magnetic Reynolds numbers up to 220 it is shown that in the kinematic regime, isotropic helical turbulence leads to an alpha effect and a turbulent diffusivity whose values are independent of the…

Astrophysics · Physics 2008-03-10 Sharanya Sur , Axel Brandenburg , Kandaswamy Subramanian

Analytical solution of ${\alpha}$-dynamo equation representing strongly torsioned helical dynamo is obtained in the thin twisted Riemannian flux tubes approximation. The $\alpha$ factor possesses a fundamental contribution from torsion…

Astrophysics · Physics 2007-12-27 Garcia de Andrade

This study aims to develop second-order relativistic viscous magnetohydrodynamics (MHD) derived from kinetic theory within an extended relaxation time approximation (momentum/energy dependent) for the collision kernel. The investigation…

High Energy Physics - Phenomenology · Physics 2024-07-24 Sunny Kumar Singh , Manu Kurian , Vinod Chandra

Transport coefficients in turbulence are comprised of correlation functions between turbulent fluctuations and efficient methods to calculate them are desirable. For example, in mean field dynamo theories used to model the growth of large…

Solar and Stellar Astrophysics · Physics 2018-12-12 Hongzhe Zhou , Eric G. Blackman

The turbulent diffusivity tensor is determined for linear shear flow turbulence using numerical simulations. For moderately strong shear, the diagonal components are found to increase quadratically with Peclet and Reynolds numbers below…

Solar and Stellar Astrophysics · Physics 2014-11-20 Eniko J. M. Madarassy , Axel Brandenburg

We develop a mean-field theory of compressibility effects in turbulent magnetohydrodynamics and passive scalar transport using the quasi-linear approximation and the spectral $\tau$-approach. We find that compressibility decreases the…

Fluid Dynamics · Physics 2019-01-14 I. Rogachevskii , N. Kleeorin , A. Brandenburg

It is found that the extra quantum constraints to the spinor components of the equal-time Wigner function given in a recent paper by Zhuang and Heinz should vanish identically. We point out here the origin of the error and give an…

High Energy Physics - Phenomenology · Physics 2009-10-09 Abdellatif Abada , Michael C. Birse , Pengfei Zhuang , Ulrich Heinz

The Boltzmann equation for inelastic Maxwell models is used to analyze nonlinear transport in a granular binary mixture in the steady simple shear flow. Two different transport processes are studied. First, the rheological properties (shear…

Statistical Mechanics · Physics 2016-08-31 Vicente Garzo

Dynamical studies of MHD turbulence on the one hand, and arguments based upon magnetic helicity on the other, have yielded seemingly contradictory estimates for the $\alpha$ parameter in turbulent dynamo theory. Here we show, with direct…

Astrophysics · Physics 2007-05-23 Hongsong Chou , George B. Field

A statistically stationary and nearly homogeneous turbulent shear flow is established by an additional volume forcing in combination with stress-free boundary conditions in the shear direction. Both turbulent energy and enstrophy are…

Chaotic Dynamics · Physics 2019-06-19 Joerg Schumacher

We carry out numerical simulations to study transport behavior about the jamming transition of a model granular material in two dimensions at zero temperature. Shear viscosity \eta is computed as a function of particle volume density \rho…

Soft Condensed Matter · Physics 2011-11-09 Peter Olsson , S. Teitel

The nonlinear theory of a "shear-current" effect in a nonrotating and nonhelical homogeneous turbulence with an imposed mean velocity shear is developed. The ''shear-current" effect is associated with the $\bar{\bf W} {\bf \times} \bar{\bf…

Astrophysics · Physics 2009-11-10 I. Rogachevskii , N. Kleeorin

In astrophysical shear flows, the Kelvin-Helmholtz (KH) instability is generally suppressed by magnetic tension provided a sufficiently strong streamwise magnetic field. This is often used to infer upper (or lower) bounds on field strengths…

Fluid Dynamics · Physics 2026-02-04 Adrian E. Fraser , Alexis K. Kaminski , Jeffrey S. Oishi

We present nonlinear mean-field alpha-Omega dynamo simulations in spherical geometry with simplified profiles of kinematic alpha effect and shear. We take magnetic helicity evolution into account by solving a dynamical equation for the…

Solar and Stellar Astrophysics · Physics 2010-12-10 Gustavo Guerrero , Piyali Chatterjee , Axel Brandenburg

We study the dynamics of spin mode by solving the axial kinetic equations under the relaxation time approximation in the presence of dissipative sources. We find transient spin modes in response to electric field with spacetime…

Nuclear Theory · Physics 2024-10-31 Shu Lin , Haiqin Tang

We investigate the first-order transport coefficients of a fluid made of quasiparticles with a temperature-dependent mass extracted from chiral models. We describe this system using an effective kinetic theory, given by the relativistic…

High Energy Physics - Phenomenology · Physics 2026-03-17 Pedro Nogarolli , Gabriel S. Denicol , Eduardo S. Fraga

We study a nonlinear quenching of turbulent magnetic diffusion and effective drift velocity of large-scale magnetic field in a developed two-dimensional MHD turbulence at large magnetic Reynolds numbers. We show that transport of the…

Astrophysics · Physics 2009-06-23 N. Kleeorin , I. Rogachevskii

We have extended our study of the competition between the drive and stabilization of plasma microinstabilities by sheared flow to include electromagnetic effects at low plasma $\beta$ (the ratio of plasma to magnetic pressure). The extended…

Plasma Physics · Physics 2015-06-16 M. D. J. Cole , S. L. Newton , S. C. Cowley , N. F. Loureiro , D. Dickinson , C. Roach , J. W. Connor

In fluids and plasmas with zonal flow reversed shear, a peculiar kind of transport barrier appears in the shearless region, one that is associated with a proper route of transition to chaos. Using a symplectic nontwist maps, which model…

Chaotic Dynamics · Physics 2015-06-03 J. D. Szezech , I. L. Caldas , S. R. Lopes , P. J. Morrison , R. L. Viana

Toroidal magnetic fields subject to the Tayler instability can transport angular momentum. We show that the Maxwell and Reynolds stress of the nonaxisymmetric field pattern depend linearly on the shear in the cylindrical gap geometry.…

Astrophysics · Physics 2009-11-13 M. Gellert , G. Rüdiger