TITLE

Anisotropic form of third-order moments and relationship to the cascade rate in axisymmetric magnetohydrodynamic turbulence

AUTHOR(S)
Podesta, J. J.; Forman, M. A.; Smith, C. W.
PUB. DATE
September 2007
SOURCE
Physics of Plasmas;Sep2007, Vol. 14 Issue 9, p092305
SOURCE TYPE
Academic Journal
DOC. TYPE
Article
ABSTRACT
Laws governing the behavior of statistical third-order moments in the inertial range are among the few rigorous results in the theory of statistically homogeneous incompressible magnetohydrodynamic turbulence. These fundamental laws apply to both isotropic and anisotropic turbulence. Assuming that the turbulence is stationary in time and statistically axisymmetric under proper rotations about the direction of the mean magnetic field, it is shown that the general mathematical form of the tensor quantities appearing in these laws is constrained by symmetry to have a particular form. Using these forms, the general solutions of the law for the vector and pseudovector third-order moments F and FC are obtained in the limit of large kinetic Reynolds number and large magnetic Reynolds number. The physical meaning of the different terms in F and FC are investigated and a method for obtaining the cascade rates of energy ε and cross-helicity εC from experimental data is described. The results show that the measurement of the cascade rates goes hand-in-hand with the measurement of the spatial anisotropy of the third-order moments F and FC. The theory developed here can be applied to measure the turbulent cascade rates of energy and cross-helicity in laboratory plasma experiments, numerical simulations, and the solar wind.
ACCESSION #
26911292

 

Related Articles

  • On spectral scaling laws for incompressible anisotropic magnetohydrodynamic turbulence. Galtier, Sébastien; Pouquet, Annick; Mangeney, André // Physics of Plasmas;Sep2005, Vol. 12 Issue 9, p092310 

    A heuristic model is given for anisotropic magnetohydrodynamics turbulence in the presence of a uniform external magnetic field B0e⁁∥. The model is valid for both moderate and strong B0 and is able to describe both the strong and weak wave turbulence regimes as well as the transition...

  • Helical shell models for MHD. Lessinnes, T.; Plunian, F.; Carati, D. // Theoretical & Computational Fluid Dynamics;Nov2009, Vol. 23 Issue 6, p439 

    A shell model for magnetohydrodynamics (MHD) is derived directly from the dynamical system driving the evolution of three helical modes interacting in a triad. The use of helical modes implies that two shell variables are required for the velocity as well as for the magnetic field. The advantage...

  • Steady-State MHD Flows in Nozzles with an External Longitudinal Magnetic Field. Brushlinskii, K. V.; Zhdanova, N. S. // Fluid Dynamics;May/Jun2004, Vol. 39 Issue 3, p474 

    Steady-state MHD flows in channels of the nozzle type in the presence of an external longitudinal magnetic field can be divided into two significantly different classes. Subcritical flows, in which the Alfvén velocity calculated from the longitudinal magnetic field is less than the plasma...

  • Control of resistive wall modes in a cylindrical tokamak with radial and poloidal magnetic field sensors. Finn, John M. // Physics of Plasmas;Sep2004, Vol. 11 Issue 9, p4361 

    A simple cylindrical linear magnetohydrodynamic model is introduced to explain recent numerical results relating to stabilization of resistive wall modes by feedback. These older results indicate that feedback with sensors detecting the perturbed poloidal magnetic field is more effective than...

  • Flow of a two-fluid plasma carrying a pulsed current in a steady-state magnetic field. Ostrovskaya, G. V. // Technical Physics;Nov2008, Vol. 53 Issue 11, p1391 

    The problem of the motion of plasma carrying a pulsed current in a steady-state magnetic field is solved in terms of two-fluid magnetohydrodynamics. The initial directions of the force and current vectors are determined, and the relations that determine their time evolution are obtained. The...

  • On the solutions of three-dimensional non-null magnetic reconnection. Al-Salti, Nasser; Hornig, Gunnar // Physics of Plasmas;Aug2009, Vol. 16 Issue 8, p082101 

    Here we present solutions of a stationary magnetohydrodynamic (MHD) model for three-dimensional (3D) magnetic reconnection in the absence of a null point. The solutions are found in the form of an expansion scheme with a localized nonideal region. A wide variety of both analytical and numerical...

  • Three-dimensional magnetohydrodynamical simulation of expanding magnetic flux ropes. Arnold, L.; Dreher, J.; Grauer, R.; Soltwisch, H.; Stein, H. // Physics of Plasmas;Apr2008, Vol. 15 Issue 4, p042106 

    Three-dimensional, time-dependent numerical simulations of the dynamics of magnetic flux ropes are presented. The simulations are targeted towards an experiment previously conducted at California Institute of Technology [P. M. Bellan and J. F. Hansen, Phys. Plasmas 5, 1991 (1998)] which aimed at...

  • Magnetohydrodynamic analysis of the interaction of magnetized plasma flow with a perfect-conducting object. Nishida, Hiroyuki; Abe, Takashi // Physics of Plasmas;May2010, Vol. 17 Issue 5, p052901 

    In this study, a supersonic and super-Alfvénic magnetized plasma flow past a perfect-conducting cylinder was simulated based on single-fluid ideal magnetohydrodynamics to clarify the piling-up process of the magnetic field frozen in the plasma flow. Therefore, the magnetic field is assumed to...

  • Blowup of certain analytic solutions of the Hall magnetohydrodynamic equations. Núñez, Manuel; Álvarez, Jorge; Rojo, Jesús // Physics of Plasmas;Jun2008, Vol. 15 Issue 6, p062104 

    A recent analytic solution of the Hall magnetohydrodynamics equations is analyzed. It is shown that its evolution in time depends upon a certain set of inequalities upon the initial values of the velocity and the magnetic field. For most of the cases, both magnitudes will blow up in a finite...

Share

Read the Article

Courtesy of THE LIBRARY OF VIRGINIA

Sorry, but this item is not currently available from your library.

Try another library?
Sign out of this library

Other Topics