B LIMITS IN H-MODE-LIKE DISCHARGES
Recent tokamak optimization studies have indicated the existence of a beta limit proportional to the plasma current. A two-step numerical optimization procedure is described for finding beta limits in tokamak configuration with peaked current and flat pressure profiles, such as are believed to be characteristic of H mode plasmas immediately after the L to H transition. Current and pressure driven instabilities are optimized independently by specifying both the averaged current density and the pressure profile also permits independent optimization of ballooning modes and the low n kink modes that arise at high beta. Results are given for the optimization of a circular cross-section tokamak, computed for one value of the plasma current. An optimized, stable equilibrium is found, with a beta that is 50% above the limit predicted for this current.
Bibliographic Reference: WRITE TO CONFEDERATION SUISSE, CENTRE DE RECHERCHES EN PHYSIQUE DES PLASMAS, ECOLE POLYTECH. FEDERALE DE LAUSANNE, 21, AVENUE DES BAINS, CH-1007 (SWITZERLAND), MENTIONING REPORT LRP 283/85, 1985
Record Number: 1989124088900 / Last updated on: 1987-01-01
Available languages: en