Role of the plasmoid instability in magnetohydrodynamic turbulence

POSTER

Abstract

The plasmoid instability in evolving current sheets has been widely studied due to its effects on the disruption of current sheets, the formation of plasmoids, and the resultant fast magnetic reconnection. In this study, we investigate the role of the plasmoid instability in two-dimensional magnetohydrodynamic (MHD) turbulence by means of high-resolution numerical simulations. At sufficiently large magnetic Reynolds number (Rm=10^6), the combined effects of dynamic alignment and turbulent intermittency lead to a copious formation of plasmoids in a multitude of intense current sheets. The disruption of current sheet structures facilitates the energy cascade towards small scales, leading to the breaking and steepening of the energy spectrum. In the plasmoid-mediated regime, the energy spectrum displays a scaling that is close to the spectral index -2.2 as proposed by recent analytic theories. We also demonstrate that the scale-dependent dynamic alignment exists in 2D MHD turbulence and the corresponding slope of the alignment angle is close to 0.25. [1] C. Dong et al., Role of the Plasmoid Instability in Magnetohydrodynamic Turbulence, arXiv:1804.07361.

Presenters

  • Chuanfei Dong

    Princeton University, Princeton Plasma Physics Laboratory

Authors

  • Chuanfei Dong

    Princeton University, Princeton Plasma Physics Laboratory

  • Liang Wang

    Princeton University, Princeton Plasma Physics Laboratory

  • Yi-Min Huang

    Princeton University, Princeton Plasma Physics Laboratory, Princeton University, Princeton Univ

  • Luca Comisso

    Columbia University, Princeton University, Columbia Univ

  • Amitava Bhattacharjee

    Princeton University, Princeton Univ, Princeton Univ, Princeton Plasma Phys Lab, Princeton University, Princeton Plasma Physics Laboratory, Princeton Plasma Physics Laboratory, Princeton Univ, LANL, PPPL, UC-Berkeley, UCLA and UW-Madison