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Title: Resistive magnetohydrodynamic reconnection: Resolving long-term, chaotic dynamics

In this paper, we address the long-term evolution of an idealised double current system entering reconnection regimes where chaotic behavior plays a prominent role. Our aim is to quantify the energetics in high magnetic Reynolds number evolutions, enriched by secondary tearing events, multiple magnetic island coalescence, and compressive versus resistive heating scenarios. Our study will pay particular attention to the required numerical resolutions achievable by modern (grid-adaptive) computations, and comment on the challenge associated with resolving chaotic island formation and interaction. We will use shock-capturing, conservative, grid-adaptive simulations for investigating trends dominated by both physical (resistivity) and numerical (resolution) parameters, and confront them with (visco-)resistive magnetohydrodynamic simulations performed with very different, but equally widely used discretization schemes. This will allow us to comment on the obtained evolutions in a manner irrespective of the adopted discretization strategy. Our findings demonstrate that all schemes used (finite volume based shock-capturing, high order finite differences, and particle in cell-like methods) qualitatively agree on the various evolutionary stages, and that resistivity values of order 0.001 already can lead to chaotic island appearance. However, none of the methods exploited demonstrates convergence in the strong sense in these chaotic regimes. At the same time, nonperturbed tests formore » showing convergence over long time scales in ideal to resistive regimes are provided as well, where all methods are shown to agree. Both the advantages and disadvantages of specific discretizations as applied to this challenging problem are discussed.« less
Authors:
; ;  [1] ;  [2] ; ;  [3] ;  [4]
  1. Centre for mathematical Plasma-Astrophysics, Department of Mathematics, KU Leuven (Belgium)
  2. Department of Applied Mathematics, The University of Leeds, Leeds LS2 9JT (United Kingdom)
  3. The Niels Bohr Institute, University of Copenhagen, KĂžbenhavn K (Denmark)
  4. School of Mathematics and Statistics, University of St. Andrews, Fife (United Kingdom)
Publication Date:
OSTI Identifier:
22220576
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physics of Plasmas; Journal Volume: 20; Journal Issue: 9; Other Information: (c) 2013 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
70 PLASMA PHYSICS AND FUSION TECHNOLOGY; CHAOS THEORY; COALESCENCE; CONVERGENCE; FINITE DIFFERENCE METHOD; MAGNETIC ISLANDS; MAGNETIC RECONNECTION; MAGNETIC REYNOLDS NUMBER; MAGNETOHYDRODYNAMICS; PLASMA SIMULATION; TEARING INSTABILITY