Impurity transport in ion- and electron-root confinement scenarios at Wendelstein 7-X

Langenberg, A.; Wegner, Th; Marchuk, O.; García-Regaña, J. M.; Pablant, N. A.; Fuchert, G.; Bozhenkov, S.; Damm, H.; Pasch, E.; Brunner, K.-J.; Knauer, J.; Beurskens, M.; Reimold, F.; Wolf, R. C.

doi:10.1088/1741-4326/ac24d4

Impurity transport in ion- and electron-root confinement scenarios at Wendelstein 7-X

Journal Article · Wed Sep 29 00:00:00 EDT 2021 · Nuclear Fusion

DOI:https://doi.org/10.1088/1741-4326/ac24d4· OSTI ID:1883319

^[1]; ^[1]; ^[2]; ^[3]; ^[4]; Fuchert, G. ^[1]; ^[1]; Damm, H. ^[1]; Pasch, E. ^[1]; ^[1]; Knauer, J. ^[1]; ^[1]; Reimold, F. ^[1]; ^[1]

Max-Planck-Institut für Plasmaphysik, Greifswald (Germany)
Institut für Energie- und Klimaforschung, Jülich (Germany)
Research Centre for Energy, Environment and Technology (CIEMAT), Madrid (Spain)
Princeton Plasma Physics Lab. (PPPL), Princeton, NJ (United States)

This paper reports on the observation of enhanced Ar impurity confinement in high density, turbulence reduced ion-root confinement (IRC) scenarios in Wendelstein 7-X (W7-X). Compared to the central electron-root confinement (CERC), Ar densities are substantially increased up to one order of magnitude and Ar flux profiles switch from slightly positive to pronounced negative fluxes all along the plasma radius in IRC. Estimations of the diffusive D and convective V transport parameter profiles using the STRAHL impurity transport code suggest a fundamentally different behavior in CERC and IRC with, compared to neoclassical values, high diffusive D and typical V profiles in CERC versus strongly reduced D and pronounced negative V profiles in IRC.

View Accepted Manuscript (DOE)

Research Organization:: Princeton Plasma Physics Laboratory (PPPL), Princeton, NJ (United States)

Sponsoring Organization:: Euratom; USDOE

Contributing Organization:: W7-X Team

Grant/Contract Number:: AC02-09CH11466

OSTI ID:: 1883319

Journal Information:: Nuclear Fusion, Journal Name: Nuclear Fusion Journal Issue: 11 Vol. 61; ISSN 0029-5515

Publisher:: IOP ScienceCopyright Statement

Country of Publication:: United States

Language:: English

References (37)

Collisional transport of impurities with flux-surface varying density in stellarators Buller, S.; Smith, H. M.; Helander, P. Journal of Plasma Physics, Vol. 84, Issue 4 https://doi.org/10.1017/s0022377818000867	journal	August 2018
Turbulent impurity transport simulations in Wendelstein 7-X plasmas García-Regaña, J. M.; Barnes, M.; Calvo, I. Journal of Plasma Physics, Vol. 87, Issue 1 https://doi.org/10.1017/s0022377820001543	journal	February 2021
Atomic Data and Modelling for Fusion: the ADAS Project Summers, H. P.; O’Mullane, M. G. 7TH INTERNATIONAL CONFERENCE ON ATOMIC AND MOLECULAR DATA AND THEIR APPLICATIONS - ICAMDATA-2010, AIP Conference Proceedings https://doi.org/10.1063/1.3585817	conference	January 2011
Core radial electric field and transport in Wendelstein 7-X plasmas Pablant, N. A.; Langenberg, A.; Alonso, A. Physics of Plasmas, Vol. 25, Issue 2 https://doi.org/10.1063/1.4999842	journal	February 2018
Prospects of X-ray imaging spectrometers for impurity transport: Recent results from the stellarator Wendelstein 7-X (invited) Langenberg, A.; Pablant, N. A.; Wegner, Th. Review of Scientific Instruments, Vol. 89, Issue 10 https://doi.org/10.1063/1.5036536	journal	October 2018
Design, capabilities, and first results of the new laser blow-off system on Wendelstein 7-X Wegner, Th.; Geiger, B.; Kunkel, F. Review of Scientific Instruments, Vol. 89, Issue 7 https://doi.org/10.1063/1.5037543	journal	July 2018
Plasma impurities observed by a pulse height analysis diagnostic during the divertor campaign of the Wendelstein 7-X stellarator Kubkowska, M.; Czarnecka, A.; Fornal, T. Review of Scientific Instruments, Vol. 89, Issue 10 https://doi.org/10.1063/1.5038850	journal	October 2018
Inference of temperature and density profiles via forward modeling of an x-ray imaging crystal spectrometer within the Minerva Bayesian analysis framework Langenberg, A.; Svensson, J.; Marchuk, O. Review of Scientific Instruments, Vol. 90, Issue 6 https://doi.org/10.1063/1.5086283	journal	June 2019
Performance of Wendelstein 7-X stellarator plasmas during the first divertor operation phase Wolf, R. C.; Alonso, A.; Äkäslompolo, S. Physics of Plasmas, Vol. 26, Issue 8 https://doi.org/10.1063/1.5098761	journal	August 2019
Charge exchange recombination spectroscopy at Wendelstein 7-X Ford, O. P.; Vanó, L.; Alonso, J. A. Review of Scientific Instruments, Vol. 91, Issue 2 https://doi.org/10.1063/1.5132936	journal	February 2020
Charge-state independent anomalous transport for a wide range of different impurity species observed at Wendelstein 7-X Langenberg, A.; Wegner, Th.; Pablant, N. A. Physics of Plasmas, Vol. 27, Issue 5 https://doi.org/10.1063/5.0004462	journal	May 2020
Laser blow-off injected impurity particle confinement times in JET and Tore Supra Mattioli, M.; Giannella, R.; Myrnas, R. Nuclear Fusion, Vol. 35, Issue 9 https://doi.org/10.1088/0029-5515/35/9/i05	journal	September 1995
Core electron-root confinement (CERC) in helical plasmas Yokoyama, M.; Maaßberg, H.; Beidler, C. D. Nuclear Fusion, Vol. 47, Issue 9 https://doi.org/10.1088/0029-5515/47/9/018	journal	August 2007
On impurity handling in high performance stellarator/heliotron plasmas Burhenn, R.; Feng, Y.; Ida, K. Nuclear Fusion, Vol. 49, Issue 6 https://doi.org/10.1088/0029-5515/49/6/065005	journal	April 2009
Core impurity transport in Alcator C-Mod L-, I- and H-mode plasmas Rice, J. E.; Reinke, M. L.; Gao, C. Nuclear Fusion, Vol. 55, Issue 3 https://doi.org/10.1088/0029-5515/55/3/033014	journal	February 2015
Flux-surface variations of the electrostatic potential in stellarators: impact on the radial electric field and neoclassical impurity transport Mollén, A.; Landreman, M.; Smith, H. M. Plasma Physics and Controlled Fusion, Vol. 60, Issue 8 https://doi.org/10.1088/1361-6587/aac700	journal	June 2018
Quasilinear particle transport from gyrokinetic instabilities in general magnetic geometry Helander, Per; Zocco, Alessandro Plasma Physics and Controlled Fusion, Vol. 60, Issue 8 https://doi.org/10.1088/1361-6587/aac8b7	journal	June 2018
On-surface potential and radial electric field variations in electron root stellarator plasmas García-Regaña, J. M.; Estrada, T.; Calvo, I. Plasma Physics and Controlled Fusion, Vol. 60, Issue 10 https://doi.org/10.1088/1361-6587/aad795	journal	August 2018
Impurity transport studies at Wendelstein 7-X by means of x-ray imaging spectrometer measurements Langenberg, A.; Warmer, F.; Fuchert, G. Plasma Physics and Controlled Fusion, Vol. 61, Issue 1 https://doi.org/10.1088/1361-6587/aaeb74	journal	November 2018
Pellet fueling experiments in Wendelstein 7-X Baldzuhn, J.; Damm, H.; Beidler, C. D. Plasma Physics and Controlled Fusion, Vol. 61, Issue 9 https://doi.org/10.1088/1361-6587/ab3567	journal	August 2019
Enhanced energy confinement after series of pellets in Wendelstein 7-X Baldzuhn, J.; Damm, H.; Beidler, C. D. Plasma Physics and Controlled Fusion, Vol. 62, Issue 5 https://doi.org/10.1088/1361-6587/ab8112	journal	April 2020
Electrostatic potential variation on the flux surface and its impact on impurity transport García-Regaña, J. M.; Beidler, C. D.; Kleiber, R. Nuclear Fusion, Vol. 57, Issue 5 https://doi.org/10.1088/1741-4326/aa5fd5	journal	March 2017
Argon impurity transport studies at Wendelstein 7-X using x-ray imaging spectrometer measurements Langenberg, A.; Pablant, N. A.; Marchuk, O. Nuclear Fusion, Vol. 57, Issue 8 https://doi.org/10.1088/1741-4326/aa70f4	journal	June 2017
Stellarator impurity flux driven by electric fields tangent to magnetic surfaces Calvo, Iván; Parra, Felix I.; Luis Velasco, José Nuclear Fusion, Vol. 58, Issue 12 https://doi.org/10.1088/1741-4326/aae8a1	journal	November 2018
Observation of anomalous impurity transport during low-density experiments in W7-X with laser blow-off injections of iron Geiger, B.; Wegner, Th.; Beidler, C. D. Nuclear Fusion, Vol. 59, Issue 4 https://doi.org/10.1088/1741-4326/aaff71	journal	February 2019
Optimization of flux-surface density variation in stellarator plasmas with respect to the transport of collisional impurities Buller, S.; Smith, H. M.; Mollén, A. Nuclear Fusion, Vol. 59, Issue 6 https://doi.org/10.1088/1741-4326/ab12a7	journal	May 2019
Plasma termination by excess pellet fueling and impurity injection in TJ-II, the Large Helical Device and Wendelstein 7-X Dinklage, A.; McCarthy, K. J.; Suzuki, C. Nuclear Fusion, Vol. 59, Issue 7 https://doi.org/10.1088/1741-4326/ab17fd	journal	May 2019
Increasing the density in Wendelstein 7-X: benefits and limitations Fuchert, G.; Brunner, K. J.; Rahbarnia, K. Nuclear Fusion, Vol. 60, Issue 3 https://doi.org/10.1088/1741-4326/ab6d40	journal	February 2020
Investigation of the neoclassical ambipolar electric field in ion-root plasmas on W7-X Pablant, N.; Langenberg, A.; Alonso, A. Nuclear Fusion, Vol. 60, Issue 3 https://doi.org/10.1088/1741-4326/ab6ea8	journal	February 2020
High-performance plasmas after pellet injections in Wendelstein 7-X Bozhenkov, S. A.; Kazakov, Y.; Ford, O. P. Nuclear Fusion, Vol. 60, Issue 6 https://doi.org/10.1088/1741-4326/ab7867	journal	May 2020
Characterization of the radial electric field and edge velocity shear in Wendelstein 7-X Carralero, D.; Estrada, T.; Windisch, T. Nuclear Fusion, Vol. 60, Issue 10 https://doi.org/10.1088/1741-4326/ab9885	journal	September 2020
Impact of the temperature ratio on turbulent impurity transport in Wendelstein 7-X Wegner, Thomas; Alcuson, Jorge Alberto; Geiger, Benedikt Nuclear Fusion https://doi.org/10.1088/1741-4326/abb869	journal	September 2020
Real-time dispersion interferometry for density feedback in fusion devices Brunner, K. J.; Akiyama, T.; Hirsch, M. Journal of Instrumentation, Vol. 13, Issue 09 https://doi.org/10.1088/1748-0221/13/09/p09002	journal	September 2018
Impurity Transport in a Mixed-Collisionality Stellarator Plasma Helander, P.; Newton, S. L.; Mollén, A. Physical Review Letters, Vol. 118, Issue 15 https://doi.org/10.1103/physrevlett.118.155002	journal	April 2017
First Observation of a Stable Highly Dissipative Divertor Plasma Regime on the Wendelstein 7-X Stellarator Zhang, D.; König, R.; Feng, Y. Physical Review Letters, Vol. 123, Issue 2 https://doi.org/10.1103/physrevlett.123.025002	journal	July 2019
Turbulence Mechanisms of Enhanced Performance Stellarator Plasmas Xanthopoulos, P.; Bozhenkov, S. A.; Beurskens, M. N. Physical Review Letters, Vol. 125, Issue 7 https://doi.org/10.1103/physrevlett.125.075001	journal	August 2020
Impurity Transport Studies in the Wendelstein 7-AS Stellarator Burhenn, Rainer; Baldzuhn, Jürgen; Brakel, Rudolf Fusion Science and Technology, Vol. 46, Issue 1 https://doi.org/10.13182/fst04-a547	journal	July 2004

Similar Records

Charge-state independent anomalous transport for a wide range of different impurity species observed at Wendelstein 7-X

Journal Article · Thu May 28 20:00:00 EDT 2020 · Physics of Plasmas · OSTI ID:1650339

Turbulence-reduced high-performance scenarios in Wendelstein 7-X

Journal Article · Sun Jul 14 20:00:00 EDT 2024 · Nuclear Fusion · OSTI ID:2426360

Investigation of the neoclassical ambipolar electric field in ion-root plasmas on W7-X

Journal Article · Tue Jan 21 19:00:00 EST 2020 · Nuclear Fusion · OSTI ID:1595801

Related Subjects

70 PLASMA PHYSICS AND FUSION TECHNOLOGY
central electron-root confinement
confinement
impurity transport
ion root
microturbulence

Impurity transport in ion- and electron-root confinement scenarios at Wendelstein 7-X

Citation Formats

References (37)

Similar Records

Related Subjects