Inverse Energy Cascade in Advanced MHD Turbulence (the RNG Method)

Inverse Cascade of Primordial Magnetic Field in MHD Turbulence

The feature of the spectrum of primordial magnetic field is studied by using renormalization group analysis in magnetohydrodynamics. Taking account of the renormalized resistivity at the fixed point, we show that the scaling of the typical scale with time obeys L(t) ∼ t2/5 for random initial condition. The magnetic fields observed in the various astrophysical scales[1] is one of the important p...

MHD inverse cascade in the early Universe

We have carried out numerical simulations of freely decaying magnetohydrodynamic (MHD) turbulence in three dimensions, which can be applied to the evolution of stochastic magnetic fields in the early Universe. For helical magnetic fields an inverse cascade effect is observed in which magnetic helicity and energy is transfered from smaller scales to larger scales, accompanied by power law growth...

The Inverse Energy Cascade of Two-Dimensional Turbulence

Inverse energy cascade in three-dimensional isotropic turbulence.

We study the statistical properties of homogeneous and isotropic three-dimensional (3D) turbulent flows. By introducing a novel way to make numerical investigations of Navier-Stokes equations, we show that all 3D flows in nature possess a subset of nonlinear evolution leading to a reverse energy transfer: from small to large scales. Up to now, such an inverse cascade was only observed in flows ...

Inverse energy cascade in nonlocal helical shell models of turbulence.

Following the exact decomposition in eigenstates of helicity for the Navier-Stokes equations in Fourier space [F. Waleffe, Phys. Fluids A 4, 350 (1992)], we introduce a modified version of helical shell models for turbulence with nonlocal triadic interactions. By using both an analytical argument and numerical simulation, we show that there exists a class of models, with a specific helical stru...