Tokamak disruptions and modelling of complex nonlinear plasma evolution by supercomputers
The operational space of the tokamak is limited by various large scale instabilities which can allow the plasma to escape confinement. The most dramatic and least understood of these is the major disruption. Major disruptions can lead to a violent termination of the plasma discharge. In a large tokamak such as JET, mega-ampere currents are quenched in a matter of milliseconds, producing forces up to 1000 tons on the wall and coils, while intense heat fluxes can also produce severe erosion of the vessel wall. Since only a limited number of hard disruptions can be tolerated during the lifetime of a large tokamak, it is important to understand the mechanisms by which disruptions occur. At CRPP a study has been carried out in collaboration with JET to try to reproduce this complex sequence of events by a resistive, nonlinear, three-dimensional magnetohydrodynamic simulation. The project has involved running CPU-intensive computations on the Cray-2 and these have resulted in the first simulation study to reproduce the entire disruption sequence with detailed agreement with experiment.
Bibliographic Reference: Article: EPFL Supercomputing Review, Nov. 91 (1991) No.3, pp. 24-28
Record Number: 199111650 / Last updated on: 1994-12-02
Original language: en
Available languages: en