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Related papers: Transition to turbulent dynamo saturation

200 papers

Direct numerical simulations (DNS) of fully-developed turbulent channel flows for very low Reynolds numbers have been performed with a larger computational box sizes than those of existing DNS. The friction Reynolds number was decreased…

Fluid Dynamics · Physics 2014-09-17 Takahiro Tsukahara , Yohji Seki , Hiroshi Kawamura , Daisuke Tochio

The dynamics of the two-dimensional (2D) state in driven tridimensional (3D) incompressible magnetohydrodynamic turbulence is investigated through high-resolution direct numerical simulations and in the presence of an external magnetic…

Solar and Stellar Astrophysics · Physics 2015-05-19 Barbara Bigot , Sebastien Galtier

The dynamo instability is investigated in the limit of infinite magnetic Prandtl number. In this limit the fluid is assumed to be very viscous so that the inertial terms can be neglected and the flow is slaved to the forcing. The forcing…

Fluid Dynamics · Physics 2015-05-20 Alexandros Alexakis

Turbulence and dynamo induced by the magnetorotational instability (MRI) are analyzed using quasi-linear statistical simulation methods. It is found that homogenous turbulence is unstable to a large scale dynamo instability, which saturates…

High Energy Astrophysical Phenomena · Physics 2015-06-01 Jonathan Squire , Amitava Bhattacharjee

The decay of homogeneous isotropic turbulence in a variable viscosity fluid with a viscosity ratio up to 15 is analyzed by means of highly resolved direct numerical simulations (DNS) at low Reynolds numbers. The question addressed by the…

Fluid Dynamics · Physics 2018-09-21 Michael Gauding , Luminita Danaila , Emilien Varea

A wide variety of astrophysical phenomena involve the flow of turbulent magnetized gas with relativistic velocity or energy density. Examples include gamma-ray bursts, active galactic nuclei, pulsars, magnetars, micro-quasars, merging…

High Energy Astrophysical Phenomena · Physics 2015-05-30 Jonathan Zrake , Andrew MacFadyen

We perform fully kinetic simulations of flows known to produce dynamo in magnetohydrodynamics (MHD), considering scenarios with low Reynolds number and high magnetic Prandtl number, relevant for galaxy cluster scale fluctuation dynamos. We…

For the understanding of planetary and stellar dynamos an overview of the major parameter dependences of convection driven dynamos in rotating spherical fluid shells is desirable. Although the computationally accessible parameter space is…

Fluid Dynamics · Physics 2009-04-29 F. H. Busse , R. D. Simitev

Plasma turbulence is ubiquitous in space and astrophysical plasmas, playing an important role in plasma energization, but the physical mechanisms leading to dissipation of the turbulent energy remain to be definitively identified. Kinetic…

Solar and Stellar Astrophysics · Physics 2016-12-06 Tak Chu Li , Gregory G. Howes , Kristopher G. Klein , Jason M. TenBarge

We investigate the impact of turbulence on magnetic reconnection through high-resolution 3D magnetohydrodynamical (MHD) simulations, spanning Lundquist numbers from $S=10^3$ to $10^6$. Building on Lazarian and Vishniac's (1999) theory,…

We show for the first time that sustained turbulence is possible at low magnetic Prandtl number for Keplerian flows with no mean magnetic flux. Our results indicate that increasing the vertical domain size is equivalent to increasing the…

Solar and Stellar Astrophysics · Physics 2016-12-21 Farrukh Nauman , Martin E. Pessah

Magnetic fields in galaxies are believed to be the result of dynamo amplification of initially weak seed fields, reaching equipartition strength inside the interstellar medium. The small-scale dynamo appears to be a viable mechanism to…

Astrophysics of Galaxies · Physics 2017-08-16 Michael Rieder , Romain Teyssier

Dynamo action owing to helically forced turbulence and large-scale shear is studied using direct numerical simulations. The resulting magnetic field displays propagating wave-like behavior. This behavior can be modelled in terms of an…

Astrophysics · Physics 2011-02-11 P. J. Käpylä , A. Brandenburg

We perform a fully self-consistent 3-D numerical simulation for a compressible, dissipative magneto-plasma driven by large-scale perturbations, that contain a fairly broader spectrum of characteristic modes, ranging from largest scales to…

Space Physics · Physics 2015-05-13 Dastgeer Shaikh , B. Dasgupta , Q. Hu , G. P. Zank

Variational turbulence is among the few approaches providing rigorous results in turbulence. In addition, it addresses a question of direct practical interest, namely the rate of energy dissipation. Unfortunately, only an upper bound is…

Fluid Dynamics · Physics 2009-10-28 Thierry Alboussiere

In strongly magnetized astrophysical plasma systems, magnetic reconnection is believed to be a primary process during which explosive energy release and particle acceleration occur, leading to significant high-energy emission. Past years…

High Energy Astrophysical Phenomena · Physics 2021-10-04 Fan Guo , Xiaocan Li , William Daughton , Hui Li , Patrick Kilian , Yi-Hsin Liu , Qile Zhang , Haocheng Zhang

In an earlier paper (physics/0006012) we had developed a method for computing the effective energy transfer between any two Fourier modes in fluid or magnetohydrodynamic (MHD) flows. This method is applied to a pseudo-spectral, direct…

chao-dyn · Physics 2007-05-23 Gaurav Dar , Mahendra K. Verma , V. Eswaran

M dwarfs are low-mass main-sequence stars, the most numerous type of stars in the solar neighbourhood, which are known to have significant magnetic activity. The aim of this work is to explore the dynamo solutions and magnetic fields of…

Solar and Stellar Astrophysics · Physics 2022-06-29 Carolina A. Ortiz-Rodríguez , Dominik R. G. Schleicher , Petri J. Käpylä , Felipe H. Navarrete

We study dynamo action in a convective layer of electrically-conducting, compressible fluid, rotating about the vertical axis. At the upper and lower bounding surfaces, perfectly-conducting boundary conditions are adopted for the magnetic…

Solar and Stellar Astrophysics · Physics 2011-11-23 Benjamin F. N. Favier , Paul J. Bushby

The small-scale turbulent dynamo is a key mechanism for amplifying galactic magnetic fields, yet the resulting field morphology remains poorly understood. Using 3D driven turbulence simulations across a range of compressibilities,…

Astrophysics of Galaxies · Physics 2026-03-25 Sasi M. Behara , Amit Seta
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