Radial electric field and ion parallel flow in the quasi-symmetric and Mirror configurations of HSX

Kumar, S. T. A.; Dobbins, T. J.; Talmadge, J. N.; Wilcox, R. S.; Anderson, D. T.

doi:10.1088/1361-6587/aab4c7

Title: Radial electric field and ion parallel flow in the quasi-symmetric and Mirror configurations of HSX

Journal Article · 06 March 2018 · Plasma Physics and Controlled Fusion

DOI: https://doi.org/10.1088/1361-6587/aab4c7 · OSTI ID:1432157

^[1]; Dobbins, T. J. ^[1]; Talmadge, J. N. ^[1]; Wilcox, R. S. ^[2]; Anderson, D. T. ^[1]

Univ. of Wisconsin, Madison, WI (United States). HSX Plasma Lab. Dept. of Electrical and Computer Engineering
Univ. of Wisconsin, Madison, WI (United States). HSX Plasma Lab. Dept. of Electrical and Computer Engineering; Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

In this paper, the radial electric field and the ion mean parallel flow are obtained in the helically symmetric experiment stellarator from toroidal flow measurements of C⁺⁶ ion at two locations on a flux surface, using the Pfirsch–Schlüter effect. Results from the standard quasi-helically symmetric magnetic configuration are compared with those from the Mirror configuration where the quasi-symmetry is deliberately degraded using auxiliary coils. For similar injected power, the quasi-symmetric configuration is observed to have significantly lower flows while the experimental observations from the Mirror geometry are in better agreement with neoclassical calculations. Finally, indications are that the radial electric field near the core of the quasi-symmetric configuration may be governed by non-neoclassical processes.

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Research Organization:: Univ. of Wisconsin, Madison, WI (United States); Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

Sponsoring Organization:: USDOE Office of Science (SC), Fusion Energy Sciences (FES) (SC-24)

Grant/Contract Number:: AC05-00OR22725; FG02-93ER54222

OSTI ID:: 1432157

Journal Information:: Plasma Physics and Controlled Fusion, Journal Name: Plasma Physics and Controlled Fusion Journal Issue: 5 Vol. 60; ISSN 0741-3335

Publisher:: IOP ScienceCopyright Statement

Country of Publication:: United States

Language:: English

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