We apply a Fourier spectral numerical method to 3D incompressible MHD turbulence with a magnetic Prandtl number Pr ≥ 1. We examine the processes by which an initially weak, large-scale seed magnetic field and an initially weak, small-scale, impulse-like seed magnetic field are amplified. We find that in both cases the magnetic energy spectrum grows at all scales. The growth rates at different a...

Estimates of small-scale turbulence from numerical model output are produced from local estimates of the spatial structure functions of model variables such as velocity and temperature. The key assumptions used are the existence of a universal statistical description of small-scale turbulence and a locally universal spatial filter for the model variables. The shape of the model spatial filter i...

A mechanism of excitation of the large-scale inertial waves in a rotating inhomogeneous turbulence due to an excitation of a large-scale instability is found. This instability is caused by a combined effect of the inhomogeneity of the turbulence and the uniform mean rotation. The source of the large-scale instability is the energy of the small-scale turbulence. We determined the range of parame...

We consider the problem of incompressible, forced, nonhelical, homogeneous, isotropic MHD turbulence with no mean magnetic field. This problem is essentially different from the case with externally imposed uniform mean field. There is no scale-by-scale equipartition between magnetic and kinetic energies as would be the case for the Alfvén-wave turbulence. The isotropic MHD turbulence is the end...

The recent achievement in the simulation study of multi-scale interaction among MHD, turbulence and transport is reported. Firstly, we discuss the formation and collapse of Internal Transport Barrier (ITB) in Tokamaks. The meso-scale structures are generated by three-wave interaction among drift wave turbulence. These structures interact each other, which generate the global mode around barrier...

Recent 21 cm radio observations of HI regions in the Small Magellanic Cloud, have revealed spatial power spectra of the intensity, which are quite similar in shape to those previously deduced for the Galaxy. The similarity, in spite the differences in the physical parameters between the Galaxy and the SMC, suggests that the shape of the power spectra reflects some underlying mechanism which is ...

The flow structure in the wake of a model wind turbine is explored under negligible and high turbulence in the freestream region of a wind tunnel at Re ∼ 7× 104. Attention is placed on the evolution of the integral scale and the contribution of the large-scale motions from the background flow. Hotwire anemometry was used to obtain the streamwise velocity at various streamwise and spanwise locat...

Turbulent flows are often observed to be organized into large-spatial-scale jets such as the familiar zonal jets in the upper levels of the Jovian atmosphere. These relatively steady large-scale jets are not forced coherently but are maintained by the much smaller spatialand temporal-scale turbulence with which they coexist. The turbulence maintaining the jets may arise from exogenous sources s...