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Related papers: Statistical Analysis of Stochastic Magnetic Fields

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In this paper, we study the development of anisotropy in strong MHD turbulence in the presence of a large scale magnetic field B 0 by analyzing the results of direct numerical simulations. Our results show that the developed anisotropy…

Plasma Physics · Physics 2017-06-14 Sita Sundar , Mahendra K. Verma , Alexandros Alexakis , Anando G. Chatterjee

We study the chaotic properties of a turbulent conducting fluid using direct numerical simulation in the Eulerian frame. The maximal Lyapunov exponent is measured for simulations with varying Reynolds number and magnetic Prandtl number. We…

Fluid Dynamics · Physics 2019-05-22 Richard Ho , Arjun Berera , Daniel Clark

We present a detailed direct numerical simulation of statistically steady, homogeneous, isotropic, two-dimensional magnetohydrodynamic (2D MHD) turbulence. Our study concentrates on the inverse cascade of the magnetic vector potential. We…

Chaotic Dynamics · Physics 2014-07-24 Debarghya Banerjee , Rahul Pandit

Magnetic helicity is conserved under ideal magnetohydrodynamics (MHD) and quasi-conserved even under a resistive process. The standard definition for magnetic helicity cannot be applied directly to an open magnetic field in a volume,…

Solar and Stellar Astrophysics · Physics 2020-05-27 Kai E. Yang , Michael S. Wheatland , Stuart A. Gilchrist

We report measurements of global dissipated power within a turbulent flow homogeneously forced at small scale by a new forcing technique. The forcing is random in both time and space within the fluid by using magnetic particles in an…

Fluid Dynamics · Physics 2017-10-31 Eric Falcon , Jean-Claude Bacri , Claude Laroche

We construct a magnetic helicity conserving dynamo theory which incorporates a calculated magnetic helicity current. In this model the fluid helicity plays a small role in large scale magnetic field generation. Instead, the dynamo process…

Astrophysics · Physics 2009-10-31 Ethan T. Vishniac , Jungyeon Cho

We investigate the evolution of magnetohydrodynamic/hydromagnetic perturbations in the presence of stochastic noise in rotating shear flows. The particular emphasis is the flows whose angular velocity decreases but specific angular momentum…

High Energy Astrophysical Phenomena · Physics 2013-07-24 Sujit K. Nath , Banibrata Mukhopadhyay , Amit K. Chattopadhyay

Magnetic fields without a direction of continuous symmetry have the generic feature that neighboring field lines exponentiate away from each other and become stochastic, hence the ideal constraint of preserving magnetic field line…

Solar and Stellar Astrophysics · Physics 2014-09-16 Yi-Min Huang , A. Bhattacharjee , Allen H. Boozer

Composed of shocked solar wind, the Earth's magnetosheath serves as a natural laboratory to study the transition of turbulence from low Alfv{\'e}n Mach number, $M_\mathrm{A}$, to high $M_\mathrm{A}$. The simultaneous observations of…

Space Physics · Physics 2020-08-05 Hui Li , Wence Jiang , Chi Wang , Daniel Verscharen , Chen Zeng , C. T. Russell , B. Giles , J. L. Burch

Turbulence dynamo deals with amplification of a seed magnetic field in a turbulent medium and has been studied mostly for uniform or spatially homogeneous seed magnetic fields. However, some astrophysical processes (e.g. jets from active…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-11 Jungyeon Cho , Hyunju Yoo

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

Turbulent motions are essential to the mixing of entrained fluids and are also capable of amplifying weak initial magnetic fields by small-scale dynamo action. Here we perform a systematic study of turbulent mixing in magnetized media,…

Astrophysics of Galaxies · Physics 2015-06-18 Sharanya Sur , Liubin Pan , Evan Scannapieco

We derive horizontal fluid motions on the solar surface over large areas covering the quiet-Sun magnetic network from local correlation tracking of convective granules imaged in continuum intensity and Doppler velocity by the Helioseismic…

Solar and Stellar Astrophysics · Physics 2016-06-29 C. R. Sangeetha , S. P. Rajaguru

Investigations of the inverse cascade of magnetic helicity are conducted with pseudospectral, three-dimensional direct numerical simulations of forced and decaying incompressible magnetohydrodynamic turbulence. The high-resolution…

Solar and Stellar Astrophysics · Physics 2013-09-23 Wolf-Christian Müller , Shiva Kumar. Malapaka

We use a global magnetohydrodynamic simulation of a geometrically thin accretion disk to investigate the locality and detailed structure of turbulence driven by the magnetorotational instability (MRI). The model disk has an aspect ratio $H…

High Energy Astrophysical Phenomena · Physics 2015-05-28 Kris Beckwith , Philip J. Armitage , Jacob B. Simon

Energy dissipation in collisionless plasmas is one of the most outstanding open questions in plasma physics. Magnetic reconnection and turbulence are two phenomena that can produce the conditions for energy dissipation. These two phenomena…

Electron and proton acceleration in three-dimensional electric and magnetic fields is studied through test particle simulations. The fields are obtained by a three-dimensional magnetohydrodynamic simulation of magnetic reconnection in slab…

Astrophysics · Physics 2008-11-26 Marco Onofri , Heinz Isliker , Loukas Vlahos

We present an analysis of data stemming from numerical simulations of decaying magnetohydrodynamic (MHD) turbulence up to grid resolution of 1536^3 points and up to Taylor Reynolds number of 1200. The initial conditions are such that the…

Solar and Stellar Astrophysics · Physics 2015-05-13 P. D. Mininni , A. Pouquet

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

We study decaying magnetohydrodynamics (MHD) turbulence stemming from the evolution of the Taylor-Green (TG) flow generalized recently to MHD, with equal viscosity and magnetic resistivity and up to equivalent grid resolutions of 2048^3…

Fluid Dynamics · Physics 2015-05-13 A. Pouquet , E. Lee , M. E. Brachet , P. D. Mininni , D. Rosenberg