First survey of finite-beta magnetic fields of W7-X
Magnetic fields are calculated for finite-beta equilibria of up to (volume-averaged beta) = 5% and rotational transform values of iota = 5/5, 5/6, 5/4 (rotational transform in the edge region) in W7-X. For these computations a system of numerical codes is used that allows the calculation of vacuum magnetic fields and the tracing of field lines (GOURDON code), the computation of fixed-boundary (VMEC code) and free-boundary equilibria (NEMEC code), the determination of the magnetic fields of these equilibria (MFBE code) and analysing of their magnetic field and magnetohydrodynamics (MHD) stability properties (JMC code). Comparisons of the finite-beta magnetic fields with the corresponding vacuum fields yield informations about the shift of the plasma column, variations of the apect ratio, the iota-profile, the magnetic mirror, the widths of the macroscopic islands and the ergodization of the edge region with increasing beta. Furthermore, the dependencies of these properties on the mass profile that is assumed in the NEMEC code are investigated.
Bibliographic Reference: Report: IPP 2/339 EN (1997) 27pp.
Availability: Available from the Max-Planck-Institut für Plasmaphysik, 85748 Garching bei München (DE)
Record Number: 199810246 / Last updated on: 1998-03-09
Original language: en
Available languages: en