THE TRANSIENT BEHAVIOUR OF THE BETA LIMIT IN ASDEX
In a previous paper it was shown that the beta limit in ASDEX follows a law beta-max = C . I/(a.B) (%,MA,m,T) with C approximately equal to 3.5 for a beta-qu (beta from equilibrium measurements) and C approximately equal to 2.8 for beta-dia (beta from a diamagnetic loop), in agreement with theoretical beam power - cannot be kept at that maximum value but decreases to a lower value. It was speculated that this decay in beta corresponds to a resistive adjustment of the current density distribution to the less favourable broad H-mode temperature profiles. In the following this transient behaviour of the beta limit is discussed and it is shown that in ASDEX H discharges the stationary beta limit (for beta-dia) lies about 20 - 30 % below the maximum value.
Bibliographic Reference: 12TH EUROPEAN CONFERENCE ON CONTROLLED FUSION AND PLASMA PHYSICS, BUDAPEST (HUNGARY), SEPT. 2-6, 1985 WRITE TO MAX-PLANCK-INSTITUT FUER PLASMAPHYSIK, 8046 GARCHING BEI MUENCHEN (GERMANY), MENTIONING REPORT IPP III/107, 1985, PP. 33-36.
Record Number: 1989124100100 / Last updated on: 1987-01-01
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