Kinetic modeling of fast electron dynamics and self-consistent magnetic fields in a reversed-field pinch
The dynamics of fast electrons in a reversed field pinch configuration is investigated by solving numerically the appropriate kinetic equation in 3 dimensions (2 dimensions in velocity space and 1 dimension in real space). To this end, a Fokker-Planck code has been developed, including Coulomb collisions, dc electric field, radial diffusion due to magnetic turbulence, ambipolar electric fields, and the self-consistent evaluation of the magnetic fields generated by the plasma itself. This has allowed the theoretical validation of the Kinetic Dynamo Model in a realistic geometry. In contrast to fluid-turbulent theories, this model predicts that the radial diffusion of fast electrons associated with stochastic magnetic fields might be able to sustain the reversed-field configuration. Quantitatively, it is found that the level of magnetic turbulence necessary to obtain the toroidal field reversal at the plasma edge is compatible with levels typically measured in reversed field pinch devices. In particular, the main parameters of standard discharges in the largest existing facility of this type have been simulated successfully.
Bibliographic Reference: Report: EUR-CEA-FC-1504 EN (1993)
Availability: Available from CEA, Département de Recherches sur la Fusion Contrôlée, Saint-Paul-lez-Durance (FR)
Record Number: 199410039 / Last updated on: 1994-11-28
Original language: en
Available languages: en