Nonlinear evolution of double tearing mode with guiding magnetic field

Journal Article · Sun May 15 04:00:00 EDT 2011 · Physics of Plasmas

DOI:https://doi.org/10.1063/1.3581064· OSTI ID:21537799

Zhang, C L; Ma, Z W ^[1]

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1. Institute for Fusion Theory and Simulation, Zhejiang University, Hangzhou 310027 (China)

Nonlinear dynamic evolution of the double tearing mode (DTM) with a guiding magnetic field (B{sub y0}) is investigated by magnetohydrodynamical numerical simulation. The dynamic process of DTM depends weakly on the guiding field in the weak guiding field regime (B{sub y0{<=}}1), but is suppressed by a strong guiding field (B{sub y0}>2). During the explosive nonlinear phase, the maximum reconnection rate ({gamma}{sub max}) increases weakly with the increase of the resistivity as {gamma}{sub max{approx}{eta}}{sup 0.06} for B{sub y0{<=}}1, but for B{sub y0}>2, {gamma}{sub max} is nearly independent of the resistivity. The maximum reconnection rate in the explosive growth phase increases with increase of the initial current sheet separation. A secondary tearing instability is observed at moderate current sheet separation. A strong guiding field suppresses the formation of a secondary island. Based on the simulation results, it is found that the secondary tearing instability occurs only when the length-to-thickness aspect ratio of the reconnection region exceeds about 20.

• OSTI ID: 21537799
• Journal Information: Physics of Plasmas, Journal Name: Physics of Plasmas Journal Issue: 5 Vol. 18; ISSN PHPAEN; ISSN 1070-664X
• Country of Publication: United States
• Language: English

Related Subjects

70 PLASMA PHYSICS AND FUSION TECHNOLOGY
COMPUTERIZED SIMULATION
EVOLUTION
FLUID MECHANICS
HYDRODYNAMICS
INSTABILITY
MAGNETIC FIELDS
MAGNETIC RECONNECTION
MAGNETOHYDRODYNAMICS
MECHANICS
NONLINEAR PROBLEMS
PLASMA INSTABILITY
PLASMA MACROINSTABILITIES
PLASMA SIMULATION
SIMULATION
TEARING INSTABILITY