Pressure and inductance effects on vertical stability of shaped tokamaks
Numerical calculations are presented to show the influence of finite pressure on the vertical stability of shaped tokamaks. High values of epsilon.beta(p) improve the vertical stability of dee-shaped tokamaks but are destabilising for an inverse dee. For highly elongated cross-sections, the pressure effect is well described by a linear dependence of the maximum value of stable internal inductance on epsilon.beta(p), with a coefficient that depends on the geometry and increases with triangularity. Stability diagrams are shown in terms of l(i,crit) versus epsilon.beta(p) for TCV- and DIII-D-like cross-sections. The effects of pressure are significant even in the absence of a surrounding wall. Current profile effects depend critically on the wall configuration: low values of l(i) increase the driving force of the instability, but are stabilising if the wall is sufficiently close.
Bibliographic Reference: Report: LRP 468/92 EN (1992) 24 pp.
Availability: Available from Confédération Suisse, Centre de Recherches en Physique des Plasmas, Ecole Polytechnique Fédérale de Lausanne, 21 avenue des Bains, 1007 Lausanne (CH)
Record Number: 199310241 / Last updated on: 1994-11-29
Original language: en
Available languages: en