Community Research and Development Information Service - CORDIS

Abstract

Stellarators and heliotrons confine plasmas by means of externally produced magnetic fields. For this reason, they cannot be axisymmetric, but they are inherently capable of steady-state operation. The confinement potential of such systems depends on the combination of a number of properties of the selected magnetic configuration, including rotational transform, shear, magnetic well or hill, field ripple, poloidal variation of int d"it l/"/B, etc. Four basic lines of research have emerged on which different groups concentrate: High-transform, high-shear stabilized configurations are being investigated by the Heliotron group, Kyoto; Moderate-transform, shear/magnetic-well stabilized configurations with access to a second stability regime are being studied by the ATF group, Oak Ridge; Moderate-transform, low-shear, magnetic-well stabilized, delta int "it dl/"/B-reduced, drift-optimized configurations are the focus of the Wendelstein group, Garching; High-transform, low-shear, magnetic-well stabilized configurations with large helical excursions of the magnetic axis are being investigated by groups in Spain and Australia. These programs will establish the relative importance of the different field properties and jointly produce a data base from which it will be possible to draw conclusions on optimal configurations. Experiments have been successful not only in achieving higher plasma parameters but also in extracting important information about the effects of shear, trapped particles, electric fields, resonances, and islands. Economically viable methods for building the required coils (continuous and modular) and vacuum vessel, with the required precision, have been demonstrated by the construction of ATF and Wendelstein VII-AS. Most of these methods can be extrapolated to reactor conditions. ////199210013/V

Additional information

Authors: CARRERAS B A, IPP, D;GRIEGER G, IPP, D;HARRIS J H, IPP, D;JOHNSON J L, IPP, D;LYON J T, IPP, D;MOTOJIMA O, IPP, D;RAU T, IPP, D;RENNER H, IPP, D;ROME J A IPP, D, IPP, D
Bibliographic Reference: REPORT IPP 2/286, 1987, AVAILABLITY: MAX-PLANCK-INSTITUT, MUENCHEN, D
Record Number: 1989126071800 / Last updated on: 1993-01-19
Category: PUBLICATION
Available languages: en