Renormalization group in MHD turbulence
The Renormalisation Group (RNG) theory is applied to magnetohydrodynamic equations written in Elsässer variables, as done by Yakhot and Orszag. As a result, a system of coupled nonlinear differential equations for the effective or turbulent viscosities is obtained. Without solving this system, it is possible to prove their exponential behaviour at the "fixed-point" and also determine the effective viscosity and resistivity. The results do not allow negative effective viscosity or resistivity, but in certain cases the system tends to zero viscosity or resistivity. The range of possible values of the turbulent Prandtl number is also determined. The system tends to different values of this number, depending on the initial values of the viscosity and resistivity, and the way the system is excited.
Bibliographic Reference: Report: IPP6/303 EN (1991) 25 pp.
Availability: Available from Max-Planck-Institut für Plasmaphysik, 8046 Garching bei München (DE)
Record Number: 199111637 / Last updated on: 1994-12-02
Original language: en
Available languages: en