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Related papers: A different approach to the MHD equilibrium

200 papers

Axisymmetric equilibria with incompressible flows of arbitrary direction are studied in the framework of magnetohydrodynamics under a variety of physically relevant side conditions. To this end a set of pertinent non-linear ODEs are…

Plasma Physics · Physics 2007-05-23 G. N. Throumoulopoulos , H. Tasso , G. Poulipoulis

Motivated by explosive releases of energy in fusion, space and astrophysical plasmas, we consider the nonlinear stability of stratified magnetohydrodynamic (MHD) equilibria against two-dimensional interchanges of straight magnetic-flux…

High Energy Astrophysical Phenomena · Physics 2024-12-10 David N. Hosking , David Wasserman , Steven C. Cowley

The equilibrium of an axisymmetric magnetically confined plasma with anisotropic resistivity and toroidal flow is investigated in the framework of magnetohydrodynamics (MHD). The stationary states are determined by an elliptic differential…

Plasma Physics · Physics 2015-06-26 G. Poulipoulis , G. N. Throumoulopoulos , H. Tasso

In ideal MHD, the magnetic flux is advected by the plasma motion, freezing flux-surfaces into the flow. An MHD equilibrium is reached when the flow relaxes and force balance is achieved. We ask what classes of MHD equilibria can be accessed…

Plasma Physics · Physics 2020-07-15 David Pfefferlé , Lyle Noakes , Yao Zhou

Magnetic relaxation drives plasma toward lower-energy equilibria under helicity constraints. In ideal magnetohydrodynamics (MHD), helicity is locally conserved, while resistive theories such as Taylor relaxation preserve only global…

Numerical Analysis · Mathematics 2026-03-13 Patrick E. Farrell , Mingdong He , Kaibo Hu , Ganghui Zhang

Ideal MHD relaxation is the topology-conserving reconfiguration of a magnetic field into a lower energy state where the net force is zero. This is achieved by modeling the plasma as perfectly conducting viscous fluid. It is an important…

Plasma Physics · Physics 2017-10-26 Christopher Berg Smiet , Simon Candelaresi , Dirk Bouwmeester

The concept of available energy of a collisionless plasma is discussed in the context of magnetic confinement. The available energy quantifies how much of the plasma energy can be converted into fluctuations (including nonlinear ones) and…

Plasma Physics · Physics 2020-03-18 Per Helander

We describe a magnetohydrodynamic (MHD) constrained energy functional for equilibrium calculations that combines the topological constraints of ideal MHD with elements of Taylor relaxation. Extremizing states allow for partially chaotic…

Plasma Physics · Physics 2012-04-03 S. R. Hudson , R. L. Dewar , M. J. Hole , M. McGann

The stellarator as a concept of magnetic confinement fusion requires careful design to confine particles effectively. A design possibility is to equip the magnetic field with a property known as quasisymmetry. Though it is generally…

Plasma Physics · Physics 2022-02-03 Eduardo Rodriguez , Amitava Bhattacharjee

This work studies the symmetries, the associated momentum map, and relative equilibria of a mechanical system consisting of a small axisymmetric magnetic body-dipole in an also axisymmetric external magnetic field that additionally exhibits…

Symplectic Geometry · Mathematics 2013-11-12 Lyudmila Grigoryeva , Juan-Pablo Ortega , Stanislav Zub

It is found that the ideal magnetohydrodynamic equilibrium of an axisymmetric gravitating magnetically confined plasma with incompressible flows is governed by a second-order elliptic differential equation for the poloidal magnetic flux…

Plasma Physics · Physics 2016-09-08 G. N. Throumoulopoulos , H. Tasso

In this work, we generalise linear magnetohydrodynamic (MHD) stability theory to include equilibrium pressure anisotropy in the fluid part of the analysis. A novel 'single-adiabatic' (SA) fluid closure is presented which is complementary to…

Plasma Physics · Physics 2015-10-29 M. Fitzgerald , M. J. Hole , Z. S. Qu

We revisit the issue of conservation of magnetic helicity and the Woltjer-Taylor relaxation theory in magnetohydrodynamics in the context of weak solutions. We introduce a relaxed system for the ideal MHD system, which decouples the effects…

Analysis of PDEs · Mathematics 2021-09-21 Daniel Faraco , Sauli Lindberg , László Székelyhidi

The equilibrium of a resistive axisymmetric plasma with purely toroidal flow surrounded by a conductor is investigated within the framework of the nonlinear magnetohydrodynamic theory. It is proved that a) the poloidal current density…

Plasma Physics · Physics 2009-10-30 G. N. Throumoulopoulos

We consider the plasma confined in a general axisymmetric spatial domain with perfect conducting boundary which reflects particles specularly, and look at a certain class of equilibria, assuming axisymmetry in the problem. We prove a sharp…

Analysis of PDEs · Mathematics 2019-10-15 Katherine Zhiyuan Zhang

The calculation of both resistive and ideal plasma equilibria amounts to solving a number of magnetic differential equations which are of the type $\vec {B}\cdot \nabla \Phi =s$. We apply the necessary and sufficient criterion for the…

Plasma Physics · Physics 2007-05-23 Wolfgang Engelhardt

We develop a theory of buoyancy instabilities of the electron-ion plasma with the heat flux based on not the MHD equations, but using the multicomponent plasma approach. We investigate a geometry in which the background magnetic field,…

Astrophysics of Galaxies · Physics 2010-03-02 Anatoly K. Nekrasov , Mohsen Shadmehri

The dynamics of the oscillator system is investigated. The conditions under which this dynamics becomes unstable are determined. In particular, it is shown that plasma in constant magnetic field becomes unstable if its density exceeds a…

Plasma Physics · Physics 2019-04-23 Vyacheslav Buts

The z-pinch is a classical steady state for the MHD model, where a confined plasma fluid is separated by vacuum, in the presence of a magnetic field which is generated by a prescribed current along the z direction. We develop a variational…

Analysis of PDEs · Mathematics 2020-03-31 Dongfen Bian , Yan Guo , Ian Tice

This overview presents a tutorial introduction to the theory of magnetic plasma confinement in toroidal confinement systems with particular emphasis on axisymmetric equilibrium geometries, and tokamaks. The discussion covers three important…

Plasma Physics · Physics 2015-09-30 Fatemeh Dini , Reza Baghdadi , Reza Amrollahi , Sina Khorasani