Magnetic reconnection via current sheets

Journal Article · Thu May 01 04:00:00 EDT 1986 · Phys. Fluids; (United States)

DOI:https://doi.org/10.1063/1.865670· OSTI ID:5937776

Biskamp, D

A general picture of magnetic reconnection in the framework of 2-D incompressible resistive magnetohydrodynamic theory is presented. Numerical studies of (quasi-) steady-state driven reconnection reveal current sheet formation for Mach numbers M = u/v/sub A/ exceeding the Sweet--Parker reconnection rate M/sub SP/ = (eta/Lv/sub A/)/sup 1//sup ///sup 2/. Since the thickness delta of the current sheet is found to be invariant to a change of the resistivity eta, its length ..delta.. increases rapidly with decreasing eta or increasing M, which can be written in the form ..delta..approx.(M/M/sub SP/)/sup 4/, so that ..delta.. reaches the global system size L within a short range of the parameter M/M/sub SP/. The results are rather insensitive to the particular choice of boundary conditions. Because of the presence of a current sheet, the overall reconnection process is quite slow. This picture essentially agrees with Syrovatsky's (Sov. Phys. JETP 33, 933 (1971)) theory and disproves Petschek's (AAS/NASA Symposium on the Physics of Solar Flares, (NASA, Washington, DC, 1964) p. 425) mechanism of fast magnetic reconnection. A theory of the solution in the external and in the diffusion region is developed and analytical expressions in agreement with the simulation results are obtained by means of a variational principle.

• Research Organization: Max-Planck-Institut fuer Plasmaphysik,8046 Garching bei Muenchen, Federal Republic of Germany
• OSTI ID: 5937776
• Journal Information: Phys. Fluids; (United States), Journal Name: Phys. Fluids; (United States) Vol. 29:5; ISSN PFLDA
• Country of Publication: United States
• Language: English

Related Subjects

640430* -- Fluid Physics-- Magnetohydrodynamics
75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
BOUNDARY CONDITIONS
DIFFUSION
DIMENSIONS
EARTH ATMOSPHERE
EARTH MAGNETOSPHERE
ELECTRIC CONDUCTIVITY
ELECTRICAL PROPERTIES
FLUID FLOW
FLUID MECHANICS
HYDRODYNAMICS
INCOMPRESSIBLE FLOW
INSTABILITY
MACH NUMBER
MAGNETIC FLUX
MAGNETOHYDRODYNAMICS
MATHEMATICS
MECHANICS
NUMERICAL ANALYSIS
PHYSICAL PROPERTIES
PLASMA INSTABILITY
PLASMA MACROINSTABILITIES
PLASMA SHEET
SIMULATION
TEARING INSTABILITY
THICKNESS
TWO-DIMENSIONAL CALCULATIONS
VELOCITY