Publication: Quasi-symmetry and the nature of radial turbulent transport in quasi-poloidal stellarators
Loading...
Identifiers
Publication date
2016-10-01
Defense date
Advisors
Tutors
Journal Title
Journal ISSN
Volume Title
Publisher
AIP Publishing
Abstract
Quasi-symmetric configurations have a better neoclassical confinement compared to that of standard stellarators. The reduction of the neoclassical viscosity along the direction of quasi-symmetry should facilitate the self-generation of zonal flows and, consequently, the mitigation of turbulent fluctuations and the ensuing radial transport. Therefore, it is expected that quasi-symmetries should also result in better confinement properties regarding radial turbulent transport. In this paper we show that, at least for quasi-poloidal configurations, the influence of quasi-symmetry on radial transport exceeds the expected reduction of fluctuation levels and associated effective transport coefficients, and that the intimate nature of transport itself is affected. In particular, radial turbulent transport becomes increasingly subdiffusive as the degree of quasi-symmetry becomes larger. This behavior is somewhat reminiscent of what has been previously reported in tokamaks with strong radially sheared zonal flows. Published by AIP Publishing.
Description
Keywords
Physics, Model
Bibliographic citation
Alcuson, J. A., Reynolds-Barredo, J. M., Bustos, A., Sanchez, R., Tribaldos, V., Xanthopoulos, P., Goerler, T., & Newman, D. E. (2016). Quasi-symmetry and the nature of radial turbulent transport in quasi-poloidal stellarators. In Physics of Plasmas, 23(10), 102308.