Repository logo

Infoscience

  • English
  • French
Log In
Logo EPFL, École polytechnique fédérale de Lausanne

Infoscience

  • English
  • French
Log In
  1. Home
  2. Academic and Research Output
  3. Journal articles
  4. On the Requirements to Control Neoclassical Tearing Modes in Burning Plasmas
 
research article

On the Requirements to Control Neoclassical Tearing Modes in Burning Plasmas

Sauter, O.  orcid-logo
•
Henderson, M. A.  
•
Ramponi, G.
Show more
2009
Plasma Physics and Controlled Fusion

Neoclassical tearing modes (NTMs) are magnetic islands which increase locally the radial transport and therefore degrade the plasma performance. They are self-sustained by the bootstrap current perturbed by the enhanced radial transport. The confinement degradation is proportional to the island width and to the position of the resonant surface. The q=2 NTMs are much more detrimental to the confinement than the 3/2 modes due to their larger radii. NTMs are metastable in typical scenarios with $N \supeq 1$ and in the region where the safety factor is increasing with radius. This is due to the fact that the local perturbed pressure gradient is sufficient to self-sustain an existing magnetic island. The main questions for burning plasmas are whether there is a trigger mechanism which will destabilize NTMs, and what is the best strategy to control/avoid the modes. The latter has to take into account the main aim which is to maximize the Q factor, but also the controllability of the scenario. Standardized and simplified equations are proposed to enable easier prediction of NTM control in burning plasmas from present experimental results. The present expected requirements for NTM control with localised ECCD (electron cyclotron current drive) in ITER are discussed in detail. Other aspects of the above questions are also discussed, in particular the role of partial stabilisation of NTMs, the possibility to control NTMs at small size with little ECH power and the differences between controlling NTMs at the resonant surface or controlling the main trigger source, for the standard scenario namely the sawteeth. It is shown that there is no unique best strategy, but several tools are needed to most efficiently reduce the impact of NTMs on burning plasmas.

  • Files
  • Details
  • Metrics
Type
research article
DOI
10.1088/0741-3335/52/2/025002
Web of Science ID

WOS:000273698200003

Author(s)
Sauter, O.  orcid-logo
Henderson, M. A.  
Ramponi, G.
Zohm, H.
Zucca, C.  
Date Issued

2009

Published in
Plasma Physics and Controlled Fusion
Volume

52

Issue

2

Article Number

025002

Subjects

tokamak

•

ITER

•

fusion

•

neoclassical tearing mode

Note

with special agreement between IOP and European Commission

URL

URL

http://www.iop.org/EJ/journal/PPCF

URL

http://crpplocal.epfl.ch/pinboard/jpapers/0907101.pdf
Editorial or Peer reviewed

REVIEWED

Written at

EPFL

EPFL units
CRPP  
SPC  
Available on Infoscience
December 5, 2009
Use this identifier to reference this record
https://infoscience.epfl.ch/handle/20.500.14299/44666
Logo EPFL, École polytechnique fédérale de Lausanne
  • Contact
  • infoscience@epfl.ch

  • Follow us on Facebook
  • Follow us on Instagram
  • Follow us on LinkedIn
  • Follow us on X
  • Follow us on Youtube
AccessibilityLegal noticePrivacy policyCookie settingsEnd User AgreementGet helpFeedback

Infoscience is a service managed and provided by the Library and IT Services of EPFL. © EPFL, tous droits réservés