Phenomenology of major and minor disruptions in high beta deuterium and tritium tokamak fusion test reactor plasma

摘要

The main subject of this work is the experimental study of the low m and n magnetohydrodynamics (MHD) perturbations during disruptive instability. This work presents the magnetic probe data, electron cyclotron emission (ECE), alpha-particle losses, and neutron flux data measured during the disruptive instability in high beta tokamak fusion test reactor (TFTR) [D. J. Grove and D. M. Meade, Nucl. Fusion 25, 1167 (1985)] plasmas. The major disruptions in high beta regimes go through several phases. The first phase is the fast (150-250 mu s) minor disruption (predisruption), causing a drop of the central temperature (and possibly, density). In this phase a powerful central m=1=1 mode initiates the sequential development of m=4=1, 3/1, 2/1, 3/2 peripheral modes, which lead to a 3/1 locked mode. The second phase is the slow thermal quench (2 ms) in the presence of a locked mode. The third phase is a fast positive current spike generation (5%-10% increase in Ip in less than 0.5 ms) and finally, the current quench occurs with a loss of 2.5 MA in 5 ms. (C) 1998 American Institute of Physics. [S1070-664X(98)00911-2]. [References: 25]