The influence of Mode coupling on the Non-linear Evolution of Tearing Modes
On the basis of tearing mode theory a simple but physically explicit model of the evolution of toroidally coupled rotating magnetic islands has been developed. The basic mechanism identified by the model in the island evolution is the locking in phase of rotating islands that leads to rapid destabilization of an initially stable mode. Destabilization of marginally stable modes is analyzed in several scenarios. It is shown that mode coupling is an effective way of destabilizing M=3 island in a low beta-plasma. The numerical examples are presented show the individual roles of coupling, inertia and resistive wall. The model was applied for the analysis of MHD observations of an ASDEX discharge.
Bibliographic Reference: Report: JET-P(99)22, 19pp.
Availability: Available from the Librarian, JET Laboratory, Abingdon (GB)
Record Number: 199911466 / Last updated on: 1999-10-08
Original language: en
Available languages: en