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The results of a numerical study of the magnetic dynamo effect in cylindrical von K\'arm\'an plasma flow are presented with parameters relevant to the Madison Plasma Couette Experiment. This experiment is designed to investigate a broad…

Plasma Physics · Physics 2012-11-09 I. V. Khalzov , B. P. Brown , F. Ebrahimi , D. D. Schnack , C. B. Forest

We perform kinematic simulations of dynamo action driven by a helical small scale flow of a conducting fluid in order to deduce mean-field properties of the combined induction action of small scale eddies. We examine two different flow…

Fluid Dynamics · Physics 2014-07-28 Andre Giesecke , Frank Stefani , Gunter Gerbeth

Many astrophysical small-scale dynamos (SSDs) amplify weak magnetic fields via highly compressible, supersonic turbulence, but established SSD theories have overlooked these compressible effects. To address this, we perform visco-resistive…

Astrophysics of Galaxies · Physics 2025-02-12 Neco Kriel , James R. Beattie , Christoph Federrath , Mark R. Krumholz , Justin Kin Jun Hew

In a forced three-dimensional turbulent flow the scales larger than the forcing scale have been conjectured to reach a thermal equilibrium state forming a $k^2$ energy spectrum. In this work we examine the properties of these large scales…

Fluid Dynamics · Physics 2019-07-24 Alexandros Alexakis , Marc-Etienne Brachet

An attractive method of obtaining an effective cosmological constant at the present epoch is through the potential energy of a scalar field. Considering models with a perfect fluid and a scalar field, we classify all potentials for which…

Astrophysics · Physics 2009-07-09 Andrew R Liddle , Robert J Scherrer

The phenomenon of drag reduction by polymer additives had been studied in simulations on the basis of non-Newtonian fluid mechanical models that take into account the field of polymer extension (conformation tensor) and its interaction with…

Fluid Dynamics · Physics 2009-11-10 Roberto Benzi , Emily S. C. Ching , Itamar Procaccia

We consider magnetic fields generated by homogeneous isotropic and parity invariant turbulent flows. We show that simple scaling laws for dynamo threshold, magnetic energy and Ohmic dissipation can be obtained depending on the value of the…

Fluid Dynamics · Physics 2009-11-13 Stephan Fauve , Francois Petrelis

A numerical study of the magnetic induction equation has been performed on von Karman type flows. These flows are generated by two co-axial counter-rotating propellers in cylindrical containers. Such devices are currently used in the von…

Fluid Dynamics · Physics 2009-11-10 L. Marie , J. Burguete , F. Daviaud , J. Leorat

A model of gauge-mediated supersymmetry breaking is constructed in which the low-energy physics depends on a single dynamical scale. Strong coupling dynamics of gauge theories plays an important role, in particular through its effects on…

High Energy Physics - Phenomenology · Physics 2016-08-25 Ann Nelson , Matthew J. Strassler

We study energy scale-transfer in Rayleigh-Taylor (RT) flows by coarse-graining in physical space without Fourier transforms, allowing scale analysis along vertical direction. Two processes are responsible for kinetic energy flux across…

Fluid Dynamics · Physics 2021-11-25 Dongxiao Zhao , Riccardo Betti , Hussein Aluie

The scrape-off layer (SOL) power width (\lambda_q) is important for predicting the heat load on divertor targets for future magnetically confined devices. Currently, the underlying physics for \lambda_q scaling is not fully understood. This…

Plasma Physics · Physics 2023-12-11 X. Liu , L. Y. Meng , J. C. Xu , L. Wang , J. Li , the EAST Team

We present hydrodynamic and magneto-hydrodynamic simulations of a liquid sodium flow using the compressible MHD code PLUTO to investigate the magnetic field regeneration in the Von-Karman-Sodium dynamo experiment. The aim of the study is to…

Plasma Physics · Physics 2017-08-08 J. Varela , S. Brun , B. Dubrulle , C. Nore

The ABC flow was originally introduced by Arnol'd to investigate Lagrangian chaos. It soon became the prototype example to illustrate magnetic-field amplification via fast dynamo action, i.e. dynamo action exhibiting magnetic-field…

Fluid Dynamics · Physics 2016-03-10 Ismaël Bouya , Emmanuel Dormy

The decay of a passive scalar in a three-dimensional chaotic flow is studied using high-resolution numerical simulations. The (volume-preserving) flow considered is a three-dimensional extension of the randomised alternating sine flow…

Chaotic Dynamics · Physics 2015-03-18 Keith Ngan , Jacques Vanneste

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

The solar dynamo problem is the question of how the cyclic variation in the solar magnetic field is maintained. One of the important processes is the transport of magnetic flux by surface convection. To reveal this process, the dependence…

Solar and Stellar Astrophysics · Physics 2016-06-07 Y. Iida

We propose a phenomenological theory of strong incompressible magnetohydrodynamic turbulence in the presence of a strong large-scale external magnetic field. We argue that in the inertial range of scales, magnetic-field and velocity-field…

Astrophysics · Physics 2007-05-23 Stanislav Boldyrev

This article proposes a Reynolds number scaling of the required grid points to perform wall-modeled LES of turbulent flows encountering separation off a solid surface. Based on comparisons between the various time scales in a…

Fluid Dynamics · Physics 2024-01-02 Rahul Agrawal , Sanjeeb Bose , Parviz Moin

The growth rate of the dynamo instability as a function of the magnetic Reynolds number Rm is investigated by means of numerical simulations for the family of the ABC flows and for 2 different forcing scales. For the ABC flows that are…

Fluid Dynamics · Physics 2015-05-28 Alexandros Alexakis

In this work, we describe a possible mechanism to set the radial scale of zonal flows, which may be applicable to the $E \times B$ staircase found in the global full-f simulations such as [G. Dif-Pradalier et al. Phys. Rev. Lett. 114,…

Plasma Physics · Physics 2026-02-24 M. Leconte , T. S. Hahm