INCOMPRESSIBLE FLR MHD + A FLUID MODEL FOR STABILITY ANALYSIS OF A FUSION PLASMA
A fluid model including FLR effects, named Incompressible Finite Larmor Radius MagnetoHydroDynamics, is presented and derived in this paper. It is an extension of ordinary, incompressible MHD to include the Larmor radius effects due to ion gyroviscosity, Hall current and electron diamagnetism. It is intended to use the model for stability analysis, on the Alfven wave time scale, of a fusion plasma and it is consequently based on transport coefficients in the collisionless limit. It is demonstrated that for a fairly dense and cool plasma, such as for the EXTRAP zpinch, all three Larmor radius effects may become important, that for a JETtype plasma no FLR effect is pronounced, and that in a reactor plasma the Hall and electron diamagnetism terms may play a role. For scaling lengths significantly smaller than the plasma radius the effect of the FLR terms becomes enhanced. The dispersion relation for a homogeneous plasma with the FLR terms included is solved exactly and the modification of the shear and compressional Alfven waves is discussed. The Perpendicular MHD model, earlier suggested by Friedberg, is discussed. When adding gyroviscosity, instability of the homogeneous plasma is found for large perpendicular wave numbers. This unphysical feature is not found in Incompressible FLR MHD.
Bibliographic Reference: WRITE TO THE DEPARTMENT OF PLASMA PHYSICS AND FUSION RESEARCH, ROYAL INSTITUTE OF TECHNOLOGY, 100 44 STOCKHOLM (SWEDEN) MENTIONING REPORT TRITA-PFU 86-09, 1986
Record Number: 1989126009200 / Last updated on: 1988-02-01
Available languages: en