Toroidal modeling of plasma response to RMP fields in ITER
Artikel i vetenskaplig tidskrift, 2017

A systematic numerical study is carried out, computing the resistive plasma response to the resonant magnetic perturbation (RMP) fields for ITER plasmas, utilizing the toroidal code MARS-F (Liu et al 2000 Phys. Plasmas 7 3681). A number of factors are taken into account, including the variation of the plasma scenarios (from 15 MA Q = 10 inductive scenario to the 9 MA Q = 5 steady state scenario), the variation of the toroidal spectrum of the applied fields (n = 1, 2, 3, 4, with n being the toroidal mode number), the amplitude and phase variation of the currents in three rows of the RMP coils as designed for ITER, and finally a special case of mixed toroidal spectrum between the n = 3 and n = 4 RMP fields. Two-dimensional parameter scans, for the edge safety factor and the coil phasing between the upper and lower rows of coils, yield 'optimal' curves that maximize a set of figures of merit, that are defined in this work to measure the plasma response. Other two-dimensional scans of the relative coil current phasing among three rows of coils, at fixed coil currents amplitude, reveal a single optimum for each coil configuration with a given n number, for the 15 MA ITER inductive plasma. On the other hand, scanning of the coil current amplitude, at fixed coil phasing, shows either synergy or cancellation effect, for the field contributions between the off-middle rows and the middle row of the RMP coils. Finally, the mixed toroidal spectrum, by combining the n = 3 and the n = 4 RMP field, results in a substantial local reduction of the amplitude of the plasma surface displacement.

plasma response

ITER

RMP fields

ELM control

Författare

L. Li

Forschungszentrum Jülich

Ministry of Education China

Donghua University

Yueqiang Liu

Chalmers, Rymd- och geovetenskap, Plasmafysik och fusionsenergi

N. Wang

Forschungszentrum Jülich

Huazhong University of Science and Technology

A. Kirk

Culham Lab

H. R. Koslowski

Forschungszentrum Jülich

Y. Liang

Institute of Plasma Physics Chinese Academy of Sciences

Donghua University

Forschungszentrum Jülich

A. Loarte

ITER

D. Ryan

University of York

Culham Lab

F. C. Zhong

Ministry of Education China

Donghua University

Plasma Physics and Controlled Fusion

0741-3335 (ISSN) 1361-6587 (eISSN)

Vol. 59

Ämneskategorier

Fusion, plasma och rymdfysik

DOI

10.1088/1361-6587/aa5769