Beta limits - MHD stability analysis for NET-ITER
For the next generation of tokamaks, only elongated cross-sections will allow operation at the beta values required to reach ignition. This report presents an optimisation of the influence of triangularity and elongation (k) on the ideal MHD beta-limit, in a particular case when k=2 and triangularity is 0.6. With increasing triangularity, the optimum current profile remains essentially unchanged from the circular case but the q-profile is strongly modified. Ballooning stability in the central region is improved, by a combination of increased shear and shaping. The beta-limit for equilibria of this type, computed using the ERATO stability code, shows several interesting features. Triangularity seems to offer the possibility of operation at relatively high beta and q(s) at moderate current with a very high value of g without an excessive sensitivity to plasma conditions at the centre.
Bibliographic Reference: Paper presented: 16th European Conference on Controlled Fusion and Plasma Physics, Venezia (IT), March 13-17, 1989
Availability: Available from (1) as Paper EN 34434 ORA
Record Number: 198910611 / Last updated on: 1994-12-01
Original language: en
Available languages: en