Speaker
Nikolai Vladimirovich Sakharov
Description
See the full Abstract at http://ocs.ciemat.es/EPS2018ABS/pdf/P2.1042.pdf
Characterization of Plasma Major Disruption in the Globus-M Spherical
Tokamak
N.V. Sakharov1, V.K. Gusev1, S. N. Kamenshchikov2 A.A. Kavin2, K. M. Lobanov2,
A.B. Mineev2, M.I. Patrov1, Yu.V. Petrov1
1
Ioffe Institute, St. Petersburg, Russia
2
JSC D.V. Efremov Scientific Research Institute of Electrophysical Apparatus, Saint
Petersburg, Russia
In this presentation we describe the characteristics of the plasma current quench during
disruptions in the Globus-M spherical tokamak. The process of current quench is
accompanied by the loss of the vertical stability of the plasma column. The plasma boundary
during the disruption is reconstructed using the algorithm of movable filaments. In
comparison with the International Disruption Database for conventional tokamaks [1] the
analysis of the data obtained in the stage of plasma current quench demonstrates a favorable,
almost linear dependence of the normalized current quench time tCQ/S on the plasma current
density Ip/S before the disruption [2]. The current induced in the vessel also increases linearly
with increasing plasma current.
The data on the current quench time and the toroidal current induced in the tokamak vessel
are compared for hydrogen and deuterium plasmas. It is shown that the disruption
characteristics depend weakly on the ion mass. The main current quench characteristics are
compared for different values of the toroidal magnetic field and different values of the
plasma safety factor before the disruption.
The distribution of the toroidal current induced in the vessel wall is determined from
magnetic measurements, and the electromagnetic loads on the vessel wall during the current
quench are calculated [3]. It is shown that the current quench results in the appearance of
bending stresses in the vessel domes of near momentless shape.
References:
[1] N. W. Eidietis, S. P. Gerhardt, R. S. Granetz et al, Nucl. Fusion 55, 063030 (2015).
[2] N. V. Sakharov, V. K. Gusev, A. D. Iblyaminova et al, Plasma Phys. Rep. 43, 422 (2017).
[3] N. V. Sakharov, V. K. Gusev, A. A. Kavin et al, Plasma Phys. Rep., to be published in 2018.
