First divertor physics studies in Wendelstein 7-X

Nuclear Fushion

article

T. Sunn Pedersen¹  R. König¹  M. Jakubowski¹  M. Krychowiak¹  D. Gradic¹  C. Killer¹  H. Niemann¹  T. Szepesi⁴  U. Wenzel¹  A. Ali¹  G. Anda⁴  J. Baldzuhn¹  T. Barbui⁵  C. Biedermann¹  B.D. Blackwell⁶  H.-S. Bosch¹  S. Bozhenkov¹  R. Brakel¹  S. Brezinsek⁷  J. Cai⁷  B. Cannas⁸  J.W. Coenen⁷  J. Cosfeld⁷  A. Dinklage¹  T. Dittmar⁷  P. Drewelow¹  P. Drews⁷  D. Dunai⁴  F. Effenberg⁵  M. Endler¹  Y. Feng¹  J. Fellinger¹  O. Ford¹  H. Frerichs⁵  G. Fuchert¹  Y. Gao⁷  J. Geiger¹  A. Goriaev⁹  K. Hammond¹  J. Harris^1,11  D. Hathiramani¹  M. Henkel⁷  Ye.O. Kazakov⁹  A. Kirschner⁷  A. Knieps⁷  M. Kobayashi^1,12  G. Kocsis⁴  P. Kornejew¹  T. Kremeyer⁵  S. Lazerzon^1,13  A. LeViness^1,13  C. Li⁷  Y. Li⁷  Y. Liang⁷  S. Liu⁷  J. Lore^1,11  S. Masuzaki^1,12  V. Moncada^1,14  O. Neubauer⁷  T.T. Ngo^1,15  J. Oelmann⁷  M. Otte¹  V. Perseo¹  F. Pisano⁸  A. Puig Sitjes¹  M. Rack⁷  M. Rasinski⁷  J. Romazanov⁷  L. Rudischhauser¹  G. Schlisio¹  J.C. Schmitt^1,16  O. Schmitz⁵  B. Schweer⁷  S. Sereda⁷  M. Sleczka³  Y. Suzuki^1,12  M. Vecsei⁴  E. Wang⁷  T. Wauters⁹  S. Wiesen⁷  V. Winters⁵  G.A. Wurden^1,17  D. Zhang¹  S. Zoletnik⁴  the W7-X Team¹ 

[1] Max-Planck-Institut für Plasmaphysik;University of Greifswald;University of Szczecin;Wigner Research Center for Physics;University of Wisconsin;Australian National University;Forschungszentrum Jülich;University of Cagliari, Via Università;Laboratory for Plasma Physics;Department of Applied Physics, Ghent University;Oak Ridge National Laboratory;National Institute for Fusion Science;Princeton Plasma Physics Laboratory, Princeton;Thermadiag;CEA;Auburn University;Los Alamos National Laboratory

关键词: stellarator;    magnetic confinement fusion;    Wendelstein 7-X;    fusion plasma;    islanddivertor;   

DOI  :  10.1088/1741-4326/ab280f

来源: Institute of Physics Publishing Ltd.

【 摘 要 】

The Wendelstein 7-X (W7-X) optimized stellarator fusion experiment, which went into operation in 2015, has been operating since 2017 with an un-cooled modular graphite divertor. This allowed first divertor physics studies to be performed at pulse energies up to 80 MJ, as opposed to 4 MJ in the first operation phase, where five inboard limiters were installed instead of a divertor. This, and a number of other upgrades to the device capabilities, allowed extension into regimes of higher plasma density, heating power, and performance overall, e.g. setting a new stellarator world record triple product. The paper focuses on the first physics studies of how the island divertor works. The plasma heat loads arrive to a very high degree on the divertor plates, with only minor heat loads seen on other components, in particular baffle structures built in to aid neutral compression. The strike line shapes and locations change significantly from one magnetic configuration to another, in very much the same way that codes had predicted they would. Strike-line widths are as large as 10 cm, and the wetted areas also large, up to about 1.5 m², which bodes well for future operation phases. Peak local heat loads onto the divertor were in general benign and project below the 10 MW m⁻² limit of the future water-cooled divertor when operated with 10 MW of heating power, with the exception of low-density attached operation in the high-iota configuration. The most notable result was the complete (in all 10 divertor units) heat-flux detachment obtained at high-density operation in hydrogen.

【 授权许可】

Unknown