Magnetic configuration scans during divertor operation of Wendelstein 7-X
Abstract
Wendelstein 7-X (W7-X) (Greifswald, Germany) is an advanced stellarator, which uses the modular coil concept to realize a magnetic configuration optimized for fusion-relevant plasma properties. The magnet system of the machine allows a variation of the rotational transform (iota) at the boundary. In the latest W7-X operational phase a dedicated configuration scan has been performed varying the rotational transform between magnetic configurations with iota = 5/4 and iota = 5/5 at the boundary. This paper presents an overview of the experiments and of the main results with respect to confinement and stability. The main observation is an increase of the plasma energy in several intermediate configurations of the scan when the 5/5-islands are close to the plasma boundary but still inside the last-closed-flux-surface. In addition, these configurations showed marked MHD-activity with a crashing behavior related to the 5/5-islands. The corresponding mode amplitude was correlated with the size of the internal 5/5 islands.
- Authors:
-
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- Max-Planck-Institute for Plasma Physics, Greifswald (Germany)
- Los Alamos National Lab. (LANL), Los Alamos, NM (United States)
- Auburn Univ., AL (United States)
- Research Centre for Energy, Environment and Technology (CIEMAT), Madrid (Spain)
- Centre for Energy Research, Budapest (Hungary)
- Forschungszentrum Juelich (Germany)
- Princeton Plasma Physics Lab. (PPPL), Princeton, NJ (United States)
- Publication Date:
- Research Org.:
- Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Princeton Plasma Physics Lab. (PPPL), Princeton, NJ (United States)
- Sponsoring Org.:
- Euratom; USDOE Office of Science (SC), Fusion Energy Sciences (FES); USDOE National Nuclear Security Administration (NNSA)
- Contributing Org.:
- The W7-X Team
- OSTI Identifier:
- 1856169
- Report Number(s):
- LA-UR-21-26646
Journal ID: ISSN 0029-5515; TRN: US2305088
- Grant/Contract Number:
- 89233218CNA000001; 633053; AC02-09CH11466; SC0014529; AC52-06NA25396
- Resource Type:
- Accepted Manuscript
- Journal Name:
- Nuclear Fusion
- Additional Journal Information:
- Journal Volume: 62; Journal Issue: 2; Journal ID: ISSN 0029-5515
- Publisher:
- IOP Science
- Country of Publication:
- United States
- Language:
- English
- Subject:
- 70 PLASMA PHYSICS AND FUSION TECHNOLOGY; magnetic fusion energy; stellarator; confinement; iota scan; configuration variation; magnetic islands; Wendelstein 7-X
Citation Formats
Andreeva, T., Geiger, J., Dinklage, A., Wurden, Glen Anthony, Thomsen, H., Rahbarnia, K., Schmitt, J. C., Hirsch, M., Fuchert, G., Nührenberg, C., Alonso, A., Beidler, C. D., Beurskens, M. N.A., Bozhenkov, S., Brakel, R., Brandt, C., Bykov, V., Grahl, M., Grulke, O., Killer, C., Kocsis, G., Klinger, T., Krämer-Flecken, A., Lazerson, S., Otte, M., Pablant, N., Schilling, J., and Windisch, T. Magnetic configuration scans during divertor operation of Wendelstein 7-X. United States: N. p., 2022.
Web. doi:10.1088/1741-4326/ac3f1b.
Andreeva, T., Geiger, J., Dinklage, A., Wurden, Glen Anthony, Thomsen, H., Rahbarnia, K., Schmitt, J. C., Hirsch, M., Fuchert, G., Nührenberg, C., Alonso, A., Beidler, C. D., Beurskens, M. N.A., Bozhenkov, S., Brakel, R., Brandt, C., Bykov, V., Grahl, M., Grulke, O., Killer, C., Kocsis, G., Klinger, T., Krämer-Flecken, A., Lazerson, S., Otte, M., Pablant, N., Schilling, J., & Windisch, T. Magnetic configuration scans during divertor operation of Wendelstein 7-X. United States. https://doi.org/10.1088/1741-4326/ac3f1b
Andreeva, T., Geiger, J., Dinklage, A., Wurden, Glen Anthony, Thomsen, H., Rahbarnia, K., Schmitt, J. C., Hirsch, M., Fuchert, G., Nührenberg, C., Alonso, A., Beidler, C. D., Beurskens, M. N.A., Bozhenkov, S., Brakel, R., Brandt, C., Bykov, V., Grahl, M., Grulke, O., Killer, C., Kocsis, G., Klinger, T., Krämer-Flecken, A., Lazerson, S., Otte, M., Pablant, N., Schilling, J., and Windisch, T. Tue .
"Magnetic configuration scans during divertor operation of Wendelstein 7-X". United States. https://doi.org/10.1088/1741-4326/ac3f1b. https://www.osti.gov/servlets/purl/1856169.
@article{osti_1856169,
title = {Magnetic configuration scans during divertor operation of Wendelstein 7-X},
author = {Andreeva, T. and Geiger, J. and Dinklage, A. and Wurden, Glen Anthony and Thomsen, H. and Rahbarnia, K. and Schmitt, J. C. and Hirsch, M. and Fuchert, G. and Nührenberg, C. and Alonso, A. and Beidler, C. D. and Beurskens, M. N.A. and Bozhenkov, S. and Brakel, R. and Brandt, C. and Bykov, V. and Grahl, M. and Grulke, O. and Killer, C. and Kocsis, G. and Klinger, T. and Krämer-Flecken, A. and Lazerson, S. and Otte, M. and Pablant, N. and Schilling, J. and Windisch, T.},
abstractNote = {Wendelstein 7-X (W7-X) (Greifswald, Germany) is an advanced stellarator, which uses the modular coil concept to realize a magnetic configuration optimized for fusion-relevant plasma properties. The magnet system of the machine allows a variation of the rotational transform (iota) at the boundary. In the latest W7-X operational phase a dedicated configuration scan has been performed varying the rotational transform between magnetic configurations with iota = 5/4 and iota = 5/5 at the boundary. This paper presents an overview of the experiments and of the main results with respect to confinement and stability. The main observation is an increase of the plasma energy in several intermediate configurations of the scan when the 5/5-islands are close to the plasma boundary but still inside the last-closed-flux-surface. In addition, these configurations showed marked MHD-activity with a crashing behavior related to the 5/5-islands. The corresponding mode amplitude was correlated with the size of the internal 5/5 islands.},
doi = {10.1088/1741-4326/ac3f1b},
journal = {Nuclear Fusion},
number = 2,
volume = 62,
place = {United States},
year = {Tue Jan 04 00:00:00 EST 2022},
month = {Tue Jan 04 00:00:00 EST 2022}
}
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