The modeling of non-axisymmetric halo currents in tokamaks
- Massachusetts Institute of Technology, Cambridge, MA (United States)
Recent experiments have firmly established the existence of non-axisymmetric modes of plasma disruption in tokamaks. The resulting halo currents driven in the vacuum chamber present a possible threat to components not designed to withstand the corresponding non-axisymmetric JxB forces. An understanding of the halo currents is necessary to insure the safety of existing tokamaks and to properly design future high-performance experiments. We have developed a model of the disrupting plasma and halo currents based on a representation of the plasma by non-axisymmetric, nested current sheets in an axisymmetric vacuum chamber. The current sheet model is more sophisticated than existing filament models in that it allows both toroidal and poloidal non-axisymmetric currents, but computationally more efficient than simulations which require flux-surface reconstruction at every time step. We will present the formulation for how a disrupting plasma in this form can drive halo currents; numerical results and scaling laws for axisymmetric cases will also be presented.
- OSTI ID:
- 489415
- Report Number(s):
- CONF-960354-; TRN: 97:011559
- Resource Relation:
- Conference: International Sherwood fusion theory conference, Philadelphia, PA (United States), 18-20 Mar 1996; Other Information: PBD: 1996; Related Information: Is Part Of 1996 international Sherwood fusion theory conference; PB: 244 p.
- Country of Publication:
- United States
- Language:
- English
Similar Records
Rotation of tokamak halo currents
MHD stability and disruptions in the SPARC tokamak