Directional multi-scale statistics of quasi-static magnetohydrodynamic turbulence

ORAL

Abstract

Anisotropy and intermittency of quasi-static magnetohydrodynamic (MHD) turbulence in an imposed magnetic field are examined, using three-dimensional orthonormal wavelet analysis. This analysis is applied to two turbulent MHD flows computed by direct numerical simulation with $512^3$ grid points and with different intensities of the imposed magnetic field. It is found that the imposed magnetic field leads to a substantial amplification of intermittency in the velocity field, especially in the direction of the imposed magnetic field. The Eulerian and Lagrangian accelerations are also examined by applying directional multi-scale analyses.

*This work was supported by the contract SiCoMHD (ANR-Blanc 2011-045).

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Authors

  • Naoya Okamoto

    • Center for Computational Science, Nagoya University, Nagoya, 464-8603, Japan

  • Katsunori Yoshimatsu

    • Department of Computational Science and Engineering, Nagoya University, Nagoya, 4648603, Japan

  • Kai Schneider

    • M2P2-CNRS and Faculte des Sciences, Aix-Marseille Universite, France
    • M2P2-CNRS \& CMI, Aix-Marseille Universite, Marseille, France

  • Marie Farge

    • LMD-CNRS-IPSL, Ecole Normale Superieure, Paris, France
    • LMD-IPSL-CNRS, Ecole Normale Superieure, 24 rue Lhomond, 75231 Paris Cedex 05, France