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Related papers: Dissipative structures in a nonlinear dynamo

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We present simulations of coherent structures in compressible flows near the transition to turbulence using the Dissipative Particle Dynamics (DPD) method. The structures we find are remarkably consistent with experimental observations and…

We present an MHD shell model suitable for computation of various energy fluxes of magnetohydrodynamic turbulence for very small and very large magnetic Prandtl numbers $\mathrm{Pm}$; such computations are inaccessible to direct numerical…

Fluid Dynamics · Physics 2016-09-21 Mahendra K. Verma , Rohit Kumar

We present numerical simulations of driven magnetohydrodynamic (MHD) turbulence with weak/moderate imposed magnetic fields. The main goal is to clarify dynamics of magnetic field growth. We also investigate the effects of the imposed…

Astrophysics · Physics 2011-02-11 J. Cho , E. Vishniac , A. Beresnyak , A. Lazarian , D. Ryu

The aim of the present work is to derive rigorous estimates for turbulent MHD flow quantities such as the size and anisotropy of the dissipative scales, as well as the transition between 2D and 3D state. To this end, we calculate an upper…

Fluid Dynamics · Physics 2020-06-11 Alban Pothérat , Thierry Alboussière

Using a closure model for the evolution of magnetic correlations, we uncover an interesting plausible saturated state of the small-scale fluctuation dynamo (SSD) and a novel anology between quantum mechanical tunneling and the generation of…

Astrophysics · Physics 2007-05-23 Kandaswamy Subramanian

The paper deals with a simple spherical mean-field dynamo model of $\alpha^2$-type in the case of high electrical conductivity. A spherically symmetric distribution of turbulent motions is assumed inside a spherical fluid body surrounded by…

Astrophysics · Physics 2007-05-23 K. -H. Raedler , U. Geppert

Astrophysical objects with negligible resistivity are often threaded by large scale magnetic fields. The generation of these fields is somewhat mysterious, since a magnetic field in a perfectly conducting fluid cannot change the flux…

Astrophysics · Physics 2007-05-23 E. T. Vishniac , A. Lazarian , J. Cho

Scale invariance is a hallmark of many natural systems, including solar flares, where energy release spans a vast range of scales. Recent computational advances, at the level of both algorithmics and hardware, have enabled high-resolution…

Recent measurements of solar wind turbulence report the presence of intermittent, exponentially distributed angular discontinuities in the magnetic field. In this Letter, we study whether such discontinuities can be produced by…

Solar and Stellar Astrophysics · Physics 2012-10-15 Vladimir Zhdankin , Stanislav Boldyrev , Joanne Mason , Jean Carlos Perez

Dynamos in astrophysical disks are usually explained in terms of the standard alpha-omega mean field dynamo model where the local helicity generates a radial field component from an azimuthal field. The subsequent shearing of the radial…

Astrophysics · Physics 2015-06-24 Ethan T. Vishniac

Magnetohydrodynamic simulations of fully convective, rotating spheres with volume heating near the center and cooling at the surface are presented. The dynamo-generated magnetic field saturates at equipartition field strength near the…

Astrophysics · Physics 2007-05-23 W. Dobler , M. Stix , A. Brandenburg

Context. An essential facet of turbulence is the space-time intermittency of the cascade of energy that leads to coherent structures of high dissipation. Aims. In this work, we attempt to investigate systematically the physical nature of…

Astrophysics of Galaxies · Physics 2022-08-31 Thibaud Richard , Pierre Lesaffre , Edith Falgarone , Andrew Lehmann

A perpendicular ion drift is investigated as a mechanism for the generation of magnetic field structures in a highly collisional dusty plasma. The basic dissipation mechanism is assumed to be the dust-neutrals momentum exchange, so that…

Plasma Physics · Physics 2009-11-13 F. Haas , P. K. Shukla

We consider the generation of magnetic field by the flow of a fluid for which the electrical conductivity is nonuniform. A new amplification mechanism is found which leads to dynamo action for flows much simpler than those considered so…

Fluid Dynamics · Physics 2016-05-04 Francois Petrelis , Alexandros Alexakis , Christophe Gissinger

Initial results from the Madison Dynamo Experiment provide details of the inductive response of a turbulent flow of liquid sodium to an applied magnetic field. The magnetic field structure is reconstructed from both internal and external…

Plasma Physics · Physics 2007-05-23 M. D. Nornberg , E. J. Spence , R. D. Kendrick , C. M. Jacobson , C. B. Forest

In presence of an externally supported, mean magnetic field a turbulent, conducting medium, such as plasma, becomes anisotropic. This mean magnetic field, which is separate from the fluctuating, turbulent part of the magnetic field, has…

Plasma Physics · Physics 2018-12-07 Riddhi Bandyopadhyay , S. Oughton , M. Wan , W. H. Matthaeus , R. Chhiber , T. N. Parashar

We present a numerical study of the magnetic field generated by an axisymmetrically forced flow in a spherical domain. At small enough Reynolds number, Re, the flow is axisymmetric and generates an equatorial dipole above a critical…

Fluid Dynamics · Physics 2009-11-13 Christophe Gissinger , Emmanuel Dormy , Stephan Fauve

We study self-assembly in a colloidal suspension of magnetic particles by performing comprehensive molecular dynamics simulations of the Stockmayer (SM) model which comprises spherical particles decorated by a magnetic moment. The SM…

Soft Condensed Matter · Physics 2023-12-12 Anuj Kumar Singh , Varsha Banerjee

We have carried out high resolution MHD simulations of the nonlinear evolution of Kelvin-Helmholtz unstable flows in 2 1/2 dimensions. The modeled flows and fields were initially uniform except for a thin shear layer with a hyperbolic…

Astrophysics · Physics 2009-10-30 T. W. Jones , Joseph B. Gaalaas , Dongsu Ryu , Adam Frank

The origin of large-scale and coherent magnetic fields in astrophysical discs is an important and long standing problem. Researchers commonly appeal to a turbulent dynamo, sustained by the magneto-rotational instability (MRI), to supply the…

High Energy Astrophysical Phenomena · Physics 2018-10-24 A. Riols , H. Latter
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