English
Related papers

Related papers: Magnetohydrodynamic activity inside a sphere

200 papers

We study exact solutions for the slow viscous flow of an infinite liquid caused by two rigid spheres approaching each either along or parallel to their line of centres, valid at all separations. This goes beyond the applicable range of…

Fluid Dynamics · Physics 2020-03-30 B. D. Goddard , R. D. Mills-Williams , J. Sun

This paper deals with the derivation and analysis of the the Hall Magneto-Hydrodynamic equations. We first provide a derivation of this system from a two-fluids Euler-Maxwell system for electrons and ions, through a set of scaling limits.…

Mathematical Physics · Physics 2014-04-08 Marion Arichetogaray , Pierre Degond , Amic Frouvelle , Jian-Guo Liu

The study of incompressible magnetohydrodynamic (MHD) turbulence gives useful insights on many astrophysical problems. We describe a pseudo-spectral MHD code suitable for the study of incompressible turbulence. We review our recent works on…

Astrophysics · Physics 2015-06-24 Jungyeon Cho

In order to solve the magnetohydrodynamics (MHD) equations with a $\mathbf{\mathcal{H}}(\mathbf{div})$-conforming element, a novel approach is proposed to ensure the exact divergence-free condition on the magnetic field. The idea is to add…

Numerical Analysis · Mathematics 2013-02-01 Wei Cai , Jian Wu , Jianguo Xin

Numerical MHD simulations play increasingly important role for understanding mechanisms of stellar magnetism. We present simulations of convection and dynamos in density-stratified rotating spherical fluid shells. We employ a new 3D…

Solar and Stellar Astrophysics · Physics 2015-09-03 Radostin D. Simitev , Alexander G. Kosovichev , Friedrich H. Busse

Magnetohydrodynamic (MHD) instabilities can play an important role in the structure and dynamics of the pulsar magnetosphere. We consider the instabilitycaused by differential rotation that is suggested by many theoretical models. Stability…

High Energy Astrophysical Phenomena · Physics 2015-06-04 V. Urpin

Electrodynamic spherical harmonic is a second rank tensor in three-dimensional space. It allows to separate the radial and angle variables in vector solutions of Maxwell's equations. Using the orthonormalization for electrodynamic spherical…

Mathematical Physics · Physics 2008-03-31 Andrey Novitsky

We study magnetic vortex-like solutions lying on the spherical surface. The simplest cylindrically symmetric vortex presents two cores (instead of one, like in open surfaces) with same charge, so repealing each other. However, the net…

Strongly Correlated Electrons · Physics 2008-09-11 G. S. Milagre , Winder A. Moura-Melo

This paper presents a novel approach for computing substructure characteristic modes. This method leverages electromagnetic scattering matrices and spherical wave expansion to directly decompose electromagnetic fields. Unlike conventional…

Classical Physics · Physics 2024-09-13 Chenbo Shi , Jin Pan , Xin Gu , Shichen Liang , Le Zuo

Obtaining observational constraints on the role of turbulent effects for the solar dynamo is a difficult, yet crucial, task. Without such knowledge, the full picture of the operation mechanism of the solar dynamo cannot be formed. The…

Solar and Stellar Astrophysics · Physics 2021-10-04 A. P. Prabhu , N. K. Singh , M. J. Käpylä , A. Lagg

We revisit the Hahm-Kulsrud-Taylor (HKT) problem, a classic prototype problem for studying resonant magnetic perturbations and 3D magnetohydrodynamical equilibria. We employ the boundary-layer techniques developed by Rosenbluth, Dagazian,…

Plasma Physics · Physics 2019-02-06 Yao Zhou , Yi-Min Huang , A. H. Reiman , Hong Qin , A. Bhattacharjee

A pseudo-spectral method with an absorbing outer boundary is used to solve a set of the time-dependent force-free equations. In the method, both electric and magnetic fields are expanded in terms of the vector spherical harmonic (VSH)…

High Energy Astrophysical Phenomena · Physics 2015-12-16 Gang Cao , Li Zhang , Sineng Sun

Single fluid magnetohydrodynamic (MHD) equations have been studied through direct numerical simulations (DNS) using pseudo-spectral methods in two as well as three spatial dimensions. At Alfv\'en resonance, a reversible periodic exchange of…

Plasma Physics · Physics 2019-06-24 Rupak Mukherjee , Rajaraman Ganesh , Abhijit Sen

A parametric study of the magnetic dipole behavior in resistive incompressible MHD inside a rotating sphere is performed, using direct numerical simulations and considering Reynolds and Ekman numbers as controlling parameters. The tendency…

Fluid Dynamics · Physics 2019-02-01 Mauro Fontana , Pablo D. Mininni , Pablo Dmitruk

Dynamo action in planetary cores has been extensively studied in the context of convectively-driven flows. We show in this letter that mechanical forcings, namely tides, libration and precession, are also able to kinematically sustain a…

Fluid Dynamics · Physics 2018-11-07 K. Sandeep Reddy , Benjamin Favier , Michael Le Bars

Electron magnetohydrodynamic (EMHD) turbulence in two dimensions is studied via high-resolution numerical simulations with a normal diffusivity. The resulting energy spectra asymptotically approach a $k^{-5/2}$ law with increasing $R_B$,…

Plasma Physics · Physics 2009-05-01 C. J. Wareing , R. Hollerbach

Macroscopic evolution of relativistic charged matter with chirality imbalance is described by the chiral magnetohydrodynamics (chiral MHD). One such astrophysical system is high-density lepton matter in core-collapse supernovae where the…

High Energy Astrophysical Phenomena · Physics 2018-10-24 Youhei Masada , Kei Kotake , Tomoya Takiwaki , Naoki Yamamoto

In this paper we present the results of time-dependent simulations of dipolar axisymmetric magnetospheres of neutron stars carried out both within the framework of relativistic magnetohydrodynamics and within the framework of resistive…

Astrophysics · Physics 2009-11-13 S. S. Komissarov

Three-dimensional numerical simulations of solar surface magnetoconvection using realistic model physics are conducted. The thermal structure of convective motions into the upper radiative layers of the photosphere, the main scales of…

Solar and Stellar Astrophysics · Physics 2015-05-13 Sergey D. Ustyugov

A variational integrator for ideal magnetohydrodynamics is derived by applying a discrete action principle to a formal Lagrangian. Discrete exterior calculus is used for the discretisation of the field variables in order to preserve their…

Numerical Analysis · Mathematics 2018-03-13 Michael Kraus , Omar Maj