Stabilisation of pressure-driven external modes in tokamaks with a resistive wall and toroidal rotationFunded under: FP3-FUSION 11C
Low n, pressure-driven external modes in tokamaks can be stabilised by the combined effect of resistive walls and toroidal plasma rotation. Sonic rotation complicates the stability problem by coupling to sound waves, for which the MHD model predicts an unphysical resonant behaviour. Reasonable approximations of the kinetic behaviour can be obtained by adding dissipative terms to the fluid equations. Three such modifications are discussed; two of these add a damping term for the Lagrangian pressure perturbations to the ideal MHD equations, while the third uses a term representing parallel viscosity in the equation of motion along the field lines. It is shown that wall stabilisation leads to experimentally significant increases in beta limit, particularly for broad pressure profiles and high q(s).
Bibliographic Reference: Article: Proceedings of the 21st EPS Conference on Controlled Fusion and Plasma Physics, pp. 544-547
Record Number: 199510143 / Last updated on: 1995-08-22
Original language: en
Available languages: en