The inverse cascade of magnetic helicity in magnetohydrodynamic turbulence

Abstract

The nonlinear dynamics of magnetic helicity, $H^M$, which is responsible for large-scale magnetic structure formation in electrically conducting turbulent media is investigated in forced and decaying three-dimensional magnetohydrodynamic turbulence. This is done with the help of high resolution direct numerical simulations and statistical closure theory. The numerically observed spectral scaling of $H^M$ is at variance with earlier work using a statistical closure model [Pouquet et al., J. Fluid Mech. \textbf{77} 321 (1976)]. By revisiting this theory a universal dynamical balance relation is found that includes effects of kinetic helicity, as well as kinetic and magnetic energy on the inverse cascade of $H^M$ and explains the above-mentioned discrepancy. Considering the result in the context of mean-field dynamo theory suggests a nonlinear modification of the $\alpha$-dynamo effect important in the context of magnetic field excitation in turbulent plasmas.

Minor corrections and improvements made

References in corpus (4)

• On the Origin of Cosmic Magnetic Fields
• Scale-Locality of Magnetohydrodynamic Turbulence
• Test-field method for mean-field coefficients with MHD background
• Advances in theory and simulations of large-scale dynamos

Cited by in corpus (28)

• Cascades and transitions in turbulent flows
• Chiral Magnetohydrodynamic Turbulence
• Reconnection-controlled decay of magnetohydrodynamic turbulence and the role of invariants
• Nonhelical turbulence and the inverse transfer of energy: A parameter study
• Variable energy flux in turbulence
• Fluctuation dynamo amplified by intermittent shear bursts in convectively driven magnetohydrodynamic turbulence
• Magnetic helicity and the evolution of decaying magnetohydrodynamic turbulence
• Helical mode interactions and spectral transfer processes in magnetohydrodynamic turbulence
• A nonlinear structural subgrid-scale closure for compressible MHD Part I: derivation and energy dissipation properties
• Reynolds-number dependence of the dimensionless dissipation rate in homogeneous magnetohydrodynamic turbulence
• Large-scale Magnetic Structure Formation in 3D-MHD Turbulence
• Helical Fluid and (Hall)-MHD Turbulence: a Brief Review
• Large-scale dynamics of magnetic helicity
• Effects of magnetic and kinetic helicities on the growth of magnetic fields in laminar and turbulent flows by helical-Fourier decomposition
• Inverse cascade and magnetic vortices in kinetic Alfvén-wave turbulence
• Triad interactions and the bidirectional turbulent cascade of magnetic helicity
• Statistics of the inverse-cascade regime in two-dimensional magnetohydrodynamic turbulence
• Comparison of forcing functions in magnetohydrodynamic turbulence
• Parameter study of decaying magnetohydrodynamic turbulence
• Role of helicities for the dynamics of turbulent magnetic fields
• Inverse cascade of hybrid helicity in $B\Omega$-MHD turbulence
• The effects of non-helical component of hypermagnetic field on the evolution of the matter-antimatter asymmetry, vorticity, and hypermagnetic field
• Reynolds number dependence of Lagrangian dispersion in direct numerical simulations of anisotropic magnetohydrodynamic turbulence
• High-order finite-volume integration schemes for subsonic magnetohydrodynamics
• Saturation of turbulent helical dynamos
• Partial invariants, large-scale dynamo action, and the inverse transfer of magnetic helicity
• Inverse transfer of magnetic helicity in direct numerical simulations of compressible isothermal turbulence: scaling laws
• Inverse transfer of magnetic helicity in direct numerical simulations of compressible isothermal turbulence: helical transfers