Speaker
Manni Jia
Description
See the full Abstract at http://ocs.ciemat.es/EPS2018ABS/pdf/P2.1031.pdf
Redistribution of three-dimensional divertor footprint induced by
time-varying resonant magnetic perturbations on EAST
M. Jia1,2 , Y. Sun2 , Y. Liang1,2 , L. Wang2 , J. Xu2 , S. Gu2 , Y. Q. Liu3 , S. Xu1,2 ,
K. Gan2 , B. Zhang2 , B. Lyu2 , W. Feng2 , H. H. Wang2 , T. Shi2 , J. Qian2 , B. Shen2
1 Forschungszentrum Jülich GmbH, Institut für Energie- und Klimaforschung-Plasmaphysik,
Partner of the Trilateral Euregio Cluster (TEC), 52425 Jülich, Germany
2 Institutes of Plasma Physics, Hefei Institutes of Physical Sciences, Chinese Academy of
Sciences, Hefei 230031, People’s Republic of China
3 Culham Centre for Fusion Energy, Abingdon, OX14 3DB, United Kingdom
The application of time-varying resonant magnetic perturbations (RMPs) is recently pro-
posed for its promising abilities of both edge localized mode (ELM) control and divertor power
load control in tokamak H-mode discharges[1]. These effects are all closely related to the three-
dimensional magnetic topology changes induced by magnetic perturbations, which can be stud-
ied with both experiments and numerical analyses. It needs to be examined on various devices
as references for future ITER operation[2]. Recently two kinds of time-varying RMPs, the rigid
rotating and up-down differential phasing RMPs, with toroidal mode number n=1 and 2 have
been examined in the EAST H-mode discharges. The observed power load distributions on the
divertor target are rotated synchronously with the rotating or phasing RMP fields. Numerical
modelings of magnetic topology, which takes into account the plasma responses calculated by
the toroidal magnetohydrodynamics code MARS-F, are carried out by the field line tracing
code TOP2D. The topology modelings show that the magnetic footprint pattern has a qualita-
tive consistency with the experimental observations[3]. The plasma response is found to play
an important role in magnetic edge topology changes as well as in the ELM-control effect[4].
With different spectra by changing the up-down phase difference, it shows an amplifying or
screening effect, which means it changes the field line penetration depth rather than the general
footprint shape. These results show the potential of making a scheme using both rotating and
phasing RMP fields with minimum current changes to achieve an even power load distribution
on divertor targets while keeping a good ELM-control effect.
References
[1] A. Loarte et al., Nuclear Fusion, 47, S203 (2007)
[2] C. J. Ham et al., Nuclear Fusion, 56, 086005 (2016)
[3] M. Jia et al., Nuclear Fusion, Accepted, (2018)
[4] Y. Sun et al., Physical Review Letters, 117(11), 115001 (2016)
