Browsing by Subject "MHD"

Now showing items 1-16 of 16

  • Anisotropic three-dimensional MHD turbulence

    Matthaeus, William H.; Ghosh, Sanjoy; Oughton, Sean; Roberts, D. Aaron (1996)
    Direct spectral method simulation of the three-dimensional magnetohydrodynamics (MHD) equations is used to explore anisotropy that develops from initially isotropic fluctuations as a consequence of a uniform applied magnetic ...
  • Commission 10: Solar Activity

    Melrose, Donald B.; Klimchuk, James A.; Benz, A.O.; Craig, Ian J.D.; Gopalswamy, N.; Harrison, R.A.; Kozlovsky, B.Z.; Poletto, G.; Schrijver, K.J.; Van Driel-Gesztelyi, L.; Wang, J.-X. (Cambridge University Press, 2007)
    Commission 10 aims at the study of various forms of solar activity, including networks, plages, pores, spots, fibrils, surges, jets, filaments/prominences, coronal loops, flares, coronal mass ejections (CMEs), solar cycle, ...
  • Coronal heating by magnetohydrodynamic turbulence driven by reflected low-frequency waves

    Matthaeus, William H.; Zank, Gary P.; Oughton, Sean; Mullan, D. J.; Dmitruk, Pablo (IOP PUBLISHING LTD, 1999)
    A candidate mechanism for the heating of the solar corona in open field line regions is described. The interaction of Alfvén waves, generated in the photosphere or chromosphere, with their reflections and the subsequent ...
  • Coronal heating distribution due to low-frequency, wave-driven turbulence

    Dmitruk, Pablo; Matthaeus, William H.; Milano, L. J.; Oughton, Sean; Zank, Gary P.; Mullan, D. J. (University of Chicago Press, 2002)
    The heating of the lower solar corona is examined using numerical simulations and theoretical models of magnetohydrodynamic turbulence in open magnetic regions. A turbulent energy cascade to small length scales perpendicular ...
  • The effect of AC magnetic fields on liquid-metal free surfaces in industrialMHD.

    Spragg, Kirk John (The University of Waikato, 2009)
    In this thesis we investigate free-surface instabilities which occur in various industrial processes involving liquid metal. Specifically, we examine a number of simple problems with a view to developing a plausible ...
  • Finite dissipation in anisotropic magnetohydrodynamic turbulence

    Bandyopadhyay, R.; Oughton, Sean; Wan, M.; Matthaeus, William H.; Chhiber, R.; Parashar, Tulasi N. (American Physical Society, 2018)
    In the presence of an externally supported, mean magnetic field, a turbulent, conducting medium, such as plasma, becomes anisotropic. This mean magnetic field, which is separate from the fluctuating, turbulent part of the ...
  • Finite-time singularity formation at a magnetic neutral line in Hall magnetohydrodynamics

    Litvinenko, Yuri E.; McMahon, Liam C. (Elsevier Ltd, 2015)
    The formation of a current sheet in a weakly collisional plasma can be modelled as a finite-time singularity solution of magnetohydrodynamic equations. We use an exact self-similar solution to confirm and generalise a ...
  • The influence of Hall currents, plasma viscosity and electron inertia on magnetic reconnection solutions

    Senanayake, Tissa (The University of Waikato, 2007)
    Abstract This thesis examines magnetic reconnection in the solar corona. Magnetic reconnection is the only mechanism which allows the magnetic topology of magnetized plasmas to be changed. Many of the dynamic processes ...
  • Mass-loading and parallel magnetized shocks

    Zank, Gary P.; Oughton, Sean; Neubauer, F. M.; Webb, G. M. (1991)
    Recent observations at comets Giacobini-Zinner and Halley suggest that simple non-reacting gas dynamics or MHD is an inappropriate description for the bow shock. The thickness of the observed (sub)shock implies that ...
  • MHD‐driven kinetic dissipation in the solar wind and corona

    Leamon, R. J.; Matthaeus, William H.; Smith, Charles W.; Zank, Gary P.; Mullan, D. J.; Oughton, Sean (University of Chicago Press, 2000)
    Mechanisms for the deposition of heat in the lower coronal plasma are discussed, emphasizing recent attempts to reconcile the fluid and kinetic perspectives. Structures at magnetohydrodynamic (MHD) scales may drive a ...
  • Nonlinear and linear timescales near kinetic scales in solar wind turbulence

    Matthaeus, William H.; Oughton, Sean; Osman, Kareem T.; Servidio, Sergio; Wan, Minping; Gary, S.P.; Shay, M.A.; Valentini, F.; Roytershteyn, V.; Karimabadi, H.; Chapman, S.C. (American Astronomical Society, 2014-08-01)
    The application of linear kinetic treatments to plasma waves, damping, and instability requires favorable inequalities between the associated linear timescales and timescales for nonlinear (e.g., turbulence) evolution. In ...
  • Properties of mass-loading shocks, 2. Magnetohydrodynamics

    Zank, Gary P.; Oughton, Sean; Neubauer, F. M.; Webb, G. M. (1992)
    The one-dimensional magnetohydrodynamics of shocked flows subjected to significant mass loading are considered. Recent observations at comets Giacobini-Zinner and Halley suggest that simple nonreacting MHD is an inappropriate ...
  • A reduced magnetohydrodynamic model of coronal heating in open magnetic regions driven by reflected low-frequency waves

    Oughton, Sean; Matthaeus, William H.; Dmitruk, Pablo; Milano, L. J.; Zank, Gary P.; Mullan, D. J. (University of Chicago Press, 2001)
    A reduced magnetohydrodynamic (RMHD) description is employed to examine a suggestion made by W. H. Matthaeus and colleagues in 1999 that coronal heating might be sustained by a cascade of low-frequency MHD turbulence. Here ...
  • Solar wind fluctuations: waves and turbulence

    Oughton, Sean (American Institute of Physics, 2003)
    We present a brief review of observations and theory regarding the nature and radial evolution of MHD‐scale solar wind fluctuations. Emphasis is placed on the fact that the fluctuations consist of both waves and turbulence, ...
  • Steady and unsteady visco-resistive reconnection in the presence of the Hall effect

    McMahon, Liam (The University of Waikato, 2021)
    In this thesis we investigate the effects of viscosity and the Hall effect on magnetic reconnection. Magnetic reconnection is a process of releasing large amounts of magnetic energy as observed in solar flares. In the first ...
  • A turbulence-driven model for heating and acceleration of the fastwind in coronal holes

    Verdini, A.; Verli, M.; Matthaeus, William H.; Oughton, Sean; Dmitruk, Pablo (IOP Publishing Ltd, 2010)
    A model is presented for generation of fast solar wind in coronal holes, relying on heating that is dominated by turbulent dissipation of MHD fluctuations transported upward in the solar atmosphere. Scale-separated transport ...