Poloidal asymmetric flow and current relaxation of ballooned transport during I-phase in ASDEX Upgrade

Journal Article · Sun May 15 00:00:00 EDT 2016 · Physics of Plasmas

DOI:https://doi.org/10.1063/1.4948787· OSTI ID:22600182

Manz, P.; Birkenmeier, G.; Medvedeva, A. ^[1]; Fuchert, G.; Cavedon, M.; Conway, G. D.; Maraschek, M.; Mink, F.; Scott, B. D. ^[2]; Shao, L. M. ^[3]; Stroth, U. ^[2]

---

1. Physik-Department E28, Technische Universität München, James-Franck-Str. 1, 85748 Garching (Germany)
2. Max-Planck-Institut für Plasmaphysik, Boltzmannstr. 2, 85748 Garching (Germany)
3. Max-Planck-Institut für Plasmaphysik, Boltzmannstr.2, 85748 Garching (Germany)

Turbulence driven poloidal asymmetric parallel flow and current perturbations are studied for tokamak plasmas of circular geometry. Whereas zonal flows can lead to in-out asymmetry of parallel flows and currents via the Pfirsch–Schlüter mechanism, ballooned transport can result in an up-down asymmetry due to the Stringer spin-up mechanism. Measurements of up-down asymmetric parallel current fluctuations occurring during the I-phase in ASDEX Upgrade are not responses to the equilibrium by the Pfirsch–Schlüter current, but can be interpreted as a response to strongly ballooned plasma transport coupled with the Stringer spin-up mechanism. A good agreement of the experimental measured limit-cycle frequencies during I-phase with the Stringer spin-up relaxation frequency is found.

• OSTI ID: 22600182
• Journal Information: Physics of Plasmas, Vol. 23, Issue 5; Other Information: (c) 2016 EURATOM; Country of input: International Atomic Energy Agency (IAEA); ISSN 1070-664X
• Country of Publication: United States
• Language: English

Related Subjects

70 PLASMA PHYSICS AND FUSION TECHNOLOGY
ASDEX TOKAMAK
ASYMMETRY
BALLOONS
CURRENTS
DISTURBANCES
EQUILIBRIUM
FLUCTUATIONS
GEOMETRY
LIMIT CYCLE
PERTURBATION THEORY
PFIRSCH-SCHLUETER REGIME
PLASMA
RELAXATION
SPIN
TRANSPORT THEORY
TURBULENCE