English
Related papers

Related papers: Energy Fluxes during Dynamo Reversals

200 papers

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

Forced turbulence simulations are used to determine the turbulent kinematic viscosity, nu_t, from the decay rate of a large scale velocity field. Likewise, the turbulent magnetic diffusivity, eta_t, is determined from the decay of a large…

Astrophysics · Physics 2007-05-23 T. A. Yousef , A. Brandenburg , G. Rüdiger

The effect of precession in a rotating sphere filled with fluid was studied with direct numerical simulations, both in the incompressible hydrodynamics (HD) and magnetohydrodynamics (MHD) scenarios. In both cases the asymptotic state and…

Fluid Dynamics · Physics 2022-12-13 Manuel I. Etchevest , Mauro Fontana , Pablo Dmitruk

Stars and gaseous planets are magnetised objects but the influence of magnetic fields on their tidal responses and dissipation rates has not been well explored. We present the first exploratory nonlinear magnetohydrodynamic (MHD)…

Solar and Stellar Astrophysics · Physics 2024-11-26 Aurélie Astoul , Adrian J. Barker

Recent theory has demonstrated a novel physics regime for magnetic reconnection in high-energy-density plasmas where the magnetic field is advected by heat flux via the Nernst effect. Here we elucidate the physics of the electron…

We present a simple numerical model of the plasma flow within the open field line tube in the pulsar magnetosphere. We study how the plasma screens the rotationally induced electric field and maintains the electric current demanded by the…

High Energy Astrophysical Phenomena · Physics 2011-02-11 Yuri Lyubarsky

We demonstrate that particles are regularly accelerated while experiencing curvature drift in flows driven by magnetic tension. Some examples of such flows include spontaneous turbulent reconnection and decaying magnetohydrodynamic (MHD)…

High Energy Astrophysical Phenomena · Physics 2016-03-04 Andrey Beresnyak , Hui Li

We report an extensive numerical study of the small-scale turbulent dynamo at large magnetic Prandtl numbers Pm. A Pm scan is given for the model case of low-Reynolds-number turbulence. We concentrate on three topics: magnetic-energy…

Astrophysics · Physics 2008-11-26 A. A. Schekochihin , S. C. Cowley , S. F. Taylor , J. L. Maron , J. C. McWilliams

We show that in decaying hydromagnetic turbulence with initial kinetic helicity, a weak magnetic field eventually becomes fully helical. The sign of magnetic helicity is opposite to that of the kinetic helicity - regardless of whether or…

The electromagnetic energy equation is analyzed term by term in a 3D simulation of kinetic reconnection previously reported by \citet{vapirev2013formation}. The evolution presents the usual 2D-like topological structures caused by an…

Plasma Physics · Physics 2015-06-18 Giovanni Lapenta , Martin Goldman , David Newman , Stefano Markidis , Andrey Divin

We use the high sensitivity to magnetic flux of mesoscopic conductance fluctuations in large quantum dots to investigate changes in the two-dimensional electron dispersion caused by an in-plane magnetic field. In particular, changes in…

Mesoscale and Nanoscale Physics · Physics 2009-11-10 D. M. Zumbuhl , J. B. Miller , C. M. Marcus , V. I. Fal'ko , T. Jungwirth , J. S. Harris

The dynamics of ultrafast energy transfer to water clusters and to bulk water by a highly intense, sub-cycle THz pulse of duration $\approx$~150~fs is investigated in the context of force-field molecular dynamics simulations. We focus our…

Atomic and Molecular Clusters · Physics 2016-07-11 Pankaj Kr. Mishra , Oriol Vendrell , Robin Santra

Reconnection of alternating magnetic fields is an important energy transformation mechanism in Poynting dominated outflows. We show that the reconnection is facilitated by the Kruskal-Schwarzschild instability of current sheets separating…

High Energy Astrophysical Phenomena · Physics 2015-05-20 Yuri Lyubarsky

Solar magnetic fields comprise an 11-year activity cycle, represented by the number of sunspots. The maintenance of such a solar magnetic field can be attributed to fluid motion in the convection zone, i.e. a dynamo. This study conducts the…

Solar and Stellar Astrophysics · Physics 2022-08-24 Ryota Shimada , Hideyuki Hotta , Takaaki Yokoyama

Bearing in mind the application to the outer crust of the neutron stars (NSs), we investigate the magnetic field decay by means of the fully relativistic Particle-In-Cell simulations. Numerical computations are carried out in 2-dimensions,…

High Energy Astrophysical Phenomena · Physics 2015-05-20 Hiroyuki R. Takahashi , Kei Kotake , Nobutoshi Yasutake

We investigate experimentally the influence of a background rotation on the energy transfers in decaying grid turbulence. The anisotropic energy flux density, ${\bf F} ({\bf r}) = < \delta {\bf u}\,(\delta {\bf u})^2 >$, where $\delta {\bf…

Fluid Dynamics · Physics 2012-05-22 Cyril Lamriben , Pierre-Philippe Cortet , Frédéric Moisy

We perform direct numerical simulations of three-dimensional freely decaying magnetohydrodynamic (MHD) turbulence. For helical magnetic fields an inverse cascade effect is observed in which power is transfered from smaller scales to larger…

Astrophysics · Physics 2009-10-31 Mattias Christensson , Mark Hindmarsh , Axel Brandenburg

We study magnetically powered relativistic outflows in which a part of the magnetic energy is dissipated internally by reconnection. For GRB parameters, and assuming that the reconnection speed scales with the Alfven speed, significant…

Astrophysics · Physics 2009-11-07 Georg Drenkhahn

Magnetic field generation in three-dimensional Rayleigh-B\'enard convection of an electrically conducting fluid is studied numerically by fixing the Prandtl number at $P=0.3$ and varying the Rayleigh number (Ra) as a control parameter. A…

Fluid Dynamics · Physics 2017-10-11 R. Chertovskih , E. L. Rempel , E. V. Chimanski

Conversion of electromagnetic energy into magnetohydrodynamic energy occurs when the electric conductivity changes from negligible to finite values. This process is relevant during the epoch of reheating of the early Universe at the end of…

Plasma Physics · Physics 2023-08-30 Axel Brandenburg , Nousaba Nasrin Protiti
‹ Prev 1 8 9 10 Next ›