Energy of linear quasi-neutral electrostatic drift waves
Certain kinds of nonlinear instabilities are related to the existence of negative-energy perturbations. In this paper an exact energy expression for linear quasi-neutral electrostatic perturbations is derived within the framework of dissipationless multi-fluid theory that is valid for any geometry. Taking the mass as a tensor with, in general, different masses parallel and perpendicular to an ambient magnetic field makes it possible to treat the full dynamics and also restrict consideration to parallel dynamics or to the completely adiabatic case. Application to slab configurations yields the result that the adiabatic approximation does not allow negative-energy perturbations, whereas inclusion of the parallel dynamics does. This is in agreement with a numerical study of drift-wave turbulence within the framework of collisional two-fluid theory.
Bibliographic Reference: Report: IPP 6/309 EN (1992) 16 pp.
Availability: Available from Max-Planck-Institut für Plasmaphysik, 8046 Garching bei München (DE)
Record Number: 199211541 / Last updated on: 1994-11-29
Original language: en
Available languages: en