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Related papers: Dynamo Transition in Low-dimensional Models

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Understanding the in situ amplification of large scale magnetic fields in turbulent astrophysical rotators has been a core subject of dynamo theory. When turbulent velocities are helical, large scale dynamos that substantially amplify…

Fluid Dynamics · Physics 2012-06-22 Jonathan Pietarila Graham , Eric G. Blackman , Pablo D. Mininni , Annick Pouquet

Magnetohydrodynamics (MHD) is a subject concerned with the dynamics of electrically conducting fluids (plasma) and can be applied in electric power generation. As a unique technology for producing direct-current electricity without moving…

Plasma Physics · Physics 2023-12-15 Osama A. Marzouk

We present a numerical and analytical study of incompressible homogeneous conducting fluids using a helical Fourier representation. We analytically study both small- and large-scale dynamo properties, as well as the inverse cascade of…

Fluid Dynamics · Physics 2017-03-02 Moritz Linkmann , Ganapati Sahoo , Mairi McKay , Arjun Berera , Luca Biferale

Stellar activity and planetary magnetospheres are powered by an underlying dynamo mechanism generated by magnetoconvection coupled with rotation. In astrophysical contexts, magnetoconvection typically occurs in parameter regimes that are…

Solar and Stellar Astrophysics · Physics 2025-12-03 Giuseppina Nigro

Models such as those involving abrupt changes in the Earth's reflectivity due to ice melt and formation often use nonlinear terms (e.g., hyperbolic tangent) to model the transition between two states. For various reasons, these models are…

Dynamical Systems · Mathematics 2015-04-21 Julie Leifeld , Kaitlin Hill , Andrew Roberts

This study seeks to elucidate the linear transient growth mechanisms in a uniform duct with square cross-section applicable to flows of electrically conducting fluids under the influence of an external magnetic field. A particular focus is…

Fluid Dynamics · Physics 2019-01-30 Oliver G. W. Cassells , Tony Vo , Alban Pothérat , Gregory J. Sheard

The connection between helically isotropic MHD turbulence and mean-field dynamo theory is reviewed. The nonlinearity in the mean-field theory is not yet well established, but detailed comparison with simulations begin to help select viable…

Astrophysics · Physics 2007-05-23 Axel Brandenburg

We study the relativistic hydrodynamics with chiral anomaly and dynamical electromagnetic fields, namely Chiral MagnetoHydroDynamics (CMHD). We formulate CMHD as a low-energy effective theory based on a generalized derivative expansion. We…

High Energy Physics - Theory · Physics 2019-12-20 Koichi Hattori , Yuji Hirono , Ho-Ung Yee , Yi Yin

Dynamo action in a fully helical Beltrami (ABC) flow is studied using both direct numerical simulations and subgrid modeling. Sufficient scale separation is given in order to allow for large-scale magnetic energy build-up. Growth of…

Fluid Dynamics · Physics 2009-11-13 P. D. Mininni

We present the results of our detailed pseudospectral direct numerical simulation (DNS) studies, with up to $1024^3$ collocation points, of incompressible, magnetohydrodynamic (MHD) turbulence in three dimensions, without a mean magnetic…

Chaotic Dynamics · Physics 2011-01-31 Ganapati Sahoo , Prasad Perlekar , Rahul Pandit

Lattice gas and lattice Boltzmann methods are recently developed numerical schemes for simulating a variety of physical systems. In this paper a new lattice Boltzmann model for modeling two-dimensional incompressible magnetohydrodynamics…

comp-gas · Physics 2009-10-22 Daniel Martinez , Shiyi Chen , William Matthaeus

Two three-dimensional magnetohydrodynamical simulations of strongly magnetized conical jets, one with a poloidal and one with a helical magnetic field, have been performed. In the poloidal simulation a significant sheath (wind) of…

Astrophysics · Physics 2009-11-07 Philip Hardee , Alexander Rosen

The Magneto-hydrodynamic (MHD) equations in the presence of a guiding magnetic field are investigated by means of direct numerical simulations. The basis of the investigation consists of 9 runs forced at the small scales. The results…

Fluid Dynamics · Physics 2015-05-30 Alexandros Alexakis

The recent demonstrations of viscous hydrodynamic electron flow in two-dimensional electron systems poses serious questions to the validity of existing transport theories, including the ballistic model, the collision-induced and…

Mesoscale and Nanoscale Physics · Physics 2022-10-05 Kirill Kapralov , Dmitry Svintsov

Earlier, Chicone, Latushkin and Montgomery-Smith [Comm Math Phys (1997)] have proved the existence of a fast dynamo operator, in compact two-dimensional manifold, as long as its Riemannian curvature be constant and negative. More recently…

Mathematical Physics · Physics 2009-11-03 L Garcia de Andrade

The decay of a turbulent magnetic field is slower with helicity than without. Furthermore, the magnetic correlation length grows faster for a helical than a nonhelical field. Both helical and nonhelical decay laws involve conserved…

Plasma Physics · Physics 2025-01-08 Axel Brandenburg , Aikya Banerjee

The main objective of this paper is to describe the dynamic transition of the incompressible MHD equations in a three dimensional (3D) rectangular domain from a perspective of pattern formation.

Mathematical Physics · Physics 2011-05-06 Taylan Sengul , Shouhong Wang

The evolution of a Taylor-Green forced magnetohydrodynamic (MHD) system showing dynamo activity is analyzed via direct numerical simulations. The statistical properties of the velocity and magnetic field in Eulerian coordinates and along…

Fluid Dynamics · Physics 2015-06-17 Holger Homann , Yannick Ponty , Giorgio Krstulovic , Rainer Grauer

When an interacting many-body system, such as a magnet, is driven in time by an external perturbation, such as a magnetic field,the system cannot respond instantaneously due to relaxational delay. The response of such a system under a…

Statistical Mechanics · Physics 2009-10-31 Bikas K Chakrabarti , Muktish Acharyya

In magnetoconvection, the flow is governed by the interplay between gravitational buoyancy and the Lorentz force, with one of these forces dominating in different regimes. In this paper, we develop a model with a single adjustable parameter…

Fluid Dynamics · Physics 2025-01-10 Matthew McCormack , Andrei Teimurazov , Olga Shishkina , Moritz Linkmann