TITLE

Nonlinear dynamics of rotating drift-tearing modes in tokamak plasmas

AUTHOR(S)
Nishimura, S.; Benkadda, S.; Yagi, M.; Itoh, S.-I.; Itoh, K.
PUB. DATE
September 2008
SOURCE
Physics of Plasmas;Sep2008, Vol. 15 Issue 9, p092506
SOURCE TYPE
Academic Journal
DOC. TYPE
Article
ABSTRACT
The rotation frequency of the drift-tearing mode is investigated with numerical simulations of reduced two-fluid equations. An extended analytical formula of the rotation frequency of the drift-tearing mode is derived, and is used to analyze numerical results. It is found that the rotation frequency depends strongly on the poloidal zonal flow generated by the drift-tearing mode. The dependence of the rotation frequency on transport coefficients is examined in the nonlinear saturation phase. It is found that ion viscosity μ and parallel resistivity η∥ play important roles by controlling the self-generated zonal flow through the change of the balance between the Reynolds stress and the Maxwell stress. The dependence of the rotation frequency on the magnetic Prandtl number μ/η∥ shows a monotonic increase.
ACCESSION #
34621633

 

Related Articles

  • A nonequilibrium representation of the turbulent viscosity based on a two-scale turbulence theory. Yoshizawa, Akira; Nisizima, Shoiti // Physics of Fluids A;Dec93, Vol. 5 Issue 12, p3302 

    A nonequilibrium expression of the turbulent viscosity in the Reynolds stress is proposed with the aid of the results from a two-scale direct-interaction approximation. The usual turbulent-viscosity model based on the turbulent kinetic energy K and its dissipation rate ε is extended to...

  • In search of zonal flows using cross-bispectrum analysis in the boundary plasma of the Hefei Tokamak-7. Xu, G. S.; Wan, B. N.; Song, M. // Physics of Plasmas;Jan2002, Vol. 9 Issue 1, p150 

    Langmuir probes have been used to measure the electrostatic Reynolds stress and the floating potential fluctuation in the boundary plasma of the Hefei Tokamak-7 (HT-7) [J. Li, B. N. Wan, and J. S. Mao, Plasma Phys. Controlled Fusion 42, 135 (2000)]. The cross bispectrum of...

  • Modeling of the dynamic subgrid-scale viscosity in large eddy simulation. Yoshizawa, Akira; Tsubokura, Makoto; Kobayashi, Toshio; Taniguchi, Nobuyuki // Physics of Fluids;Aug96, Vol. 8 Issue 8, p2254 

    Examines dynamic subgrid-scale (SGS) viscosity on the basis of the production process of the SGS Reynolds stress. Model for the SGS viscosity; Applications of the model to a channel flow; Results of comparisons with other models.

  • Modeling of compressible effects on the Reynolds stress using a Markovianized two-scale method. Akira Yoshizawa; Liou, William W. // Physics of Fluids;Oct97, Vol. 9 Issue 10, p3024 

    Reports that compressibility effects on the Reynolds stress are modeled using a Markovianized two-scale method. Effect on the turbulent viscosity; Deviation of the Reynolds stress from a turbulent-viscosity representation; Application of a simple model with the former compressibility effect to...

  • Fast wave poloidal flow generation in a plasma. Wang, C.Y.; Jaeger, E.F.; Batchelor, D.B.; Sidikman, K.L. // Physics of Plasmas;Dec94, Vol. 1 Issue 12, p3890 

    Focuses on fast wave poloidal flow generation at the plasma edge of a tokamak with a one-dimensional slab model. Generation of the poloidal flow in the absence of mode conversion; Role of the electromagnetic force in the flow generation; Importance of the plasma Reynolds stress in the flow...

  • Derivation of a model Reynolds-stress transport equation using the renormalization of the eddy-viscosity-type representation. Yoshizawa, Akira // Physics of Fluids A;Mar93, Vol. 5 Issue 3, p707 

    Terms in an asymptotic expansion for the Reynolds stress with the eddy-viscosity approximation as the leading part are summed up partially but infinitely. This renormalization procedure leads to a model Reynolds-stress transport equation. The equation is shown to retain the important structures...

  • A rescaled elliptic relaxation approach: Neutralizing the effect on the log layer. Manceau, R.; Carlson, J. R.; Gatski, T. B. // Physics of Fluids;Nov2002, Vol. 14 Issue 11, p3868 

    An alternative scaling for the relaxation function describing the velocity pressure-gradient correlation used in the elliptic relaxation procedure for both eddy-viscosity and Reynolds stress models is presented. While other alternatives have been proposed to neutralize the adverse effect on...

  • Reynolds stress closure for nonequilibrium effects in turbulent flows. Hamlington, Peter E.; Dahm, Werner J. A. // Physics of Fluids;Nov2008, Vol. 20 Issue 11, p115101 

    From consideration of turbulence anisotropy dynamics due to spatial or temporal variations in the mean strain rate, a new Reynolds stress closure for nonequilibrium effects in turbulent flows has been developed. This closure, formally derived from the Reynolds stress anisotropy transport...

  • A mixed large eddy simulation model based on the residual-based variational multiscale formulation. Wang, Z.; Oberai, A. A. // Physics of Fluids;Jul2010, Vol. 22 Issue 7, p075107 

    A mixed model based on the residual-based variational multiscale (RBVM) formulation is proposed for the large eddy simulation of turbulent flows. In this model the cross stresses are modeled by the RBVM term and the Reynolds stresses are represented by a Smagorinsky eddy viscosity. The mixed...

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