Self-organization and energy relaxation in a three-dimensional magnetohydrodynamic plasma

Journal Article · Tue Apr 01 04:00:00 EST 1986 · Phys. Fluids; (United States)

DOI:https://doi.org/10.1063/1.865862· OSTI ID:6092085

Horiuchi, R; Sato, T

A three-dimensional self-organization process in an incompressible dissipative plasma is investigated in detail by means of a magnetohydrodynamic simulation. In an initial phase the total magnetic energy rapidly decreases via magnetic reconnection driven by a global ideal unstable mode, while the total magnetic helicity decreases very slowly throughout the simulation run. This selective dissipation is found to be caused by the excitation of nonhelical, small spatial scale structures of the magnetic field (''magnetic bubble'') in the vicinity of the reconnection points. Magnetic reconnection takes place at minimum points of the magnetic helicity density where the magnetic bubbles are predominantly created. The disappearance of the bubbles leads to a rapid dissipation of the total magnetic energy. While the magnetic helicity is globally conserved during this process, its spectral density is transferred to the low wavenumber region (''inverse cascade''). After the rapid dissipation of the magnetic energy, the magnetic configuration adjusts itself to a stable equilibrium with a minimum energy without any drastic decrease in the magnetic energy and helicity. The final stable state takes either an axially symmetric configuration or a helically symmetric configuration depending on the initial condition, which is in good agreement with the relaxation theory.

• Research Organization: Institute for Fusion Theory, Hiroshima University, Hiroshima 730, Japan
• OSTI ID: 6092085
• Journal Information: Phys. Fluids; (United States), Journal Name: Phys. Fluids; (United States) Vol. 29:4; ISSN PFLDA
• Country of Publication: United States
• Language: English

Related Subjects

70 PLASMA PHYSICS AND FUSION TECHNOLOGY
700105* -- Fusion Energy-- Plasma Research-- Plasma Kinetics-Theoretical-- (-1987)
ENERGY
ENERGY LOSSES
FLUID FLOW
FLUID MECHANICS
HELICITY
HYDRODYNAMICS
INCOMPRESSIBLE FLOW
LOSSES
MAGNETIC FLUX
MAGNETOHYDRODYNAMICS
MECHANICS
PARTICLE PROPERTIES
PLASMA
RELAXATION
SELF-ENERGY
SIMULATION
THREE-DIMENSIONAL CALCULATIONS