A self-consistent renormalization scheme has been applied to nonhelical magnetohydrodynamic (MHD) turbulence with zero cross helicity. Kolmogorov's 5/3 power law has been shown to be a consistent solution for d> or =d(c) approximately 2.2. For Kolmogorov's solution, both renormalized viscosity and resistivity are positive for the whole range of parameters. Various cascade rates and Kolmogorov's...

Recent observations have revealed that magnetohydrodynamic (MHD) waves and oscillations are ubiquitous in the solar atmosphere, with a wide range of periods. We give a brief review of some aspects of MHD waves and coronal seismology that have recently been the focus of intense debate or are newly emerging. In particular, we focus on four topics: (i) the current controversy surrounding propagati...

We construct magnetohydrodynamic (MHD) similarity rebound shocks joining ‘quasistatic’ asymptotic solutions around the central degenerate core to explore an MHD model for the evolution of random magnetic field in supernova explosions. This provides a theoretical basis for further studying synchrotron diagnostics, MHD shock acceleration of cosmic rays, and the nature of intense magnetic field in...

Results from a three-dimensional axisymmetric resistive magnetohydrodynamic ~MHD! simulation are compared to experimental data from the Swarthmore Spheromak Experiment ~SSX! @M. R. Brown, Phys. Plasmas 6, 1717 ~1999!#. The MHD simulation is run under conditions and with dimensionless parameters similar to the experiment ~Lundquist number S51000, plasma beta b 50.1). The simulation is shown to r...

Wave and oscillatory activity is observed with modern imaging and spectral instruments in the visible light, EUV, X-ray and radio bands in all parts of the solar corona. Magnetohydrodynamic (MHD) wave theory gives satisfactory interpretation of these phenomena in terms of MHD modes of coronal structures. The paper reviews the current trends in the observational study of coronal oscillations, re...

Galactic HI is a gas that is coupled to magnetic field because of its fractional ionization. Many properties of HI are affected by turbulence. Recently, there has been a significant breakthrough on the theory of magnetohydrodynamic (MHD) turbulence. For the first time in the history of the subject we have a scaling model that is supported by numerical simulations. We review recent progress in s...

A new class of antenna based on magnetohydrodynamic technique is presented. Magnetohydrodynamic Antenna, using electrically conducting fluid, such as NaCl solution under controlled electromagnetic fields is formulated and developed. Fluid resonator volume and electric field with magnetic field decides the resonant frequency and return loss respectively to make the antenna tuneable in the freque...

We investigate the global large amplitude waves propagating across the solar disk as observed by the SOHO/Extreme Ultraviolet Imaging Telescope (EIT). These waves appear to be similar to those observed in H in the chromosphere and which are known as “Moreton waves,” associated with large solar flares [Moreton, 1960, 1964]. Uchida [1968] interpreted these Moreton waves as the propagation of a hy...

Poloidal rotation is routinely observed in present-day tokamak experiments, in particular near the plasma edge and in the high-confinement mode of operation. According to the magnetohydrodynamic (MHD) equilibrium theory [R. Betti and J. P. Freidberg, Phys. Plasmas 7, 2439 (2000)], radial discontinuities form when the poloidal velocity exceeds the poloidal sound speed (or rather, more correctly,...

We present a dynamical spectral model for large-eddy simulation of the incompressible magnetohydrodynamic (MHD) equations based on the eddy damped quasinormal Markovian approximation. This model extends classical spectral large-eddy simulations for the Navier-Stokes equations to incorporate general (non-Kolmogorovian) spectra as well as eddy noise. We derive the model for MHD flows and show tha...