Effects of Net Currents on the Magnetic Configuration of W7-X

✍ Scribed by J. Geiger; C.D. Beidler; M. Drevlak; H. Maaßberg; C. Nührenberg; Y. Suzuki; Yu. Turkin

• Book ID: 102813256
• Publisher: John Wiley and Sons
• Year: 2010
• Tongue: English
• Weight: 668 KB
• Volume: 50
• Category: Article
• ISSN: 0005-8025
• DOI: 10.1002/ctpp.200900028

✦ Synopsis

Abstract

Configurations deviating from the optimum high‐mirror configuration of W7‐X may show significant bootstrap currents being detrimental for proper island divertor operation. Two basic scenarios to reconcile this are investigated with respect to equilibrium, stability and boundary structures. The first scenario with freely evolving bootstrap current realizes proper divertor operation by adjusting the vacuum magnetic field. As the bootstrap current evolves on the L/R time scale (40s) this needs long discharges. The second scenario compensates the net current by proper ECCD keeping the boundary structures basically constant sacrificing the low‐shear t ‐profile (mismatching ECCD and bootstrap current). Both scenarios seem to be viable experimental candidates. The present study needs further elaboration for more consistency between transport and equilibrium calculations (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)