Initial stage of the discharge in a tokamak

Journal Article · Sun May 01 04:00:00 EDT 1977 · Sov. J. Plasma Phys. (Engl. Transl.); (United States)

OSTI ID:5233361

Abramov, V A; Vikhrev, V V; Pogutse, O P

A time-varying one-dimensional model for the initial stage of a discharge in a toroidal system is studied. A numerical solution is found for the system of nonlinear partial differential equations including the equation for the electron density, the equation for the average energy of the electric field, and Ohm's law. The energy losses due to ionization and radiation are taken into account. An expression of the Bohm type is used for the diffusion coefficients. It is shown that this breakdown model leads to plausible estimates of the ionization time and the behavior of this time as a function of the basic plasma properties. The model is extremely insensitive to the least accurately known properties: the diffusion coefficients and the thermal conductivities. There is a critical value of the electric field, V/sub 1/: At VV/sub 1/ there is a pronounced skin effect. This skin effect is displayed most significantly in the current distribution. There is a clearly defined minimum in the behavior of the current through the plasma, which ionizes the gas, as a function of the applied electric field.

• Research Organization: I. V. Kurchatov Institute of Atomic Energy, Moscow
• OSTI ID: 5233361
• Journal Information: Sov. J. Plasma Phys. (Engl. Transl.); (United States), Journal Name: Sov. J. Plasma Phys. (Engl. Transl.); (United States) Vol. 3:3; ISSN SJPPD
• Country of Publication: United States
• Language: English

Related Subjects

70 PLASMA PHYSICS AND FUSION TECHNOLOGY
700105* -- Fusion Energy-- Plasma Research-- Plasma Kinetics-Theoretical-- (-1987)
ANNULAR SPACE
BREAKDOWN
CLOSED PLASMA DEVICES
CONFIGURATION
DIFFUSION
ELECTRIC DISCHARGES
IONIZATION
SKIN EFFECT
THERMONUCLEAR DEVICES
TOKAMAK DEVICES
TOROIDAL CONFIGURATION