Dependence on plasma shape and plasma fueling for small edge-localized mode regimes in TCV and ASDEX Upgrade

B. Labit, T. Eich, G.F. Harrer, D. Gahle, S. Henderson

Research output: Contribution to journalArticle

4 Citations (Scopus)

Abstract

Within the EUROfusion MST1 work package, a series of experiments has been conducted on AUG and TCV devices to disentangle the role of plasma fueling and plasma shape for the onset of small ELM regimes. On both devices, small ELM regimes with high confinement are achieved if and only if two conditions are fulfilled at the same time. Firstly, the plasma density at the separatrix must be large enough (n e,sep/n G ∼ 0.3), leading to a pressure profile flattening at the separatrix, which stabilizes type-I ELMs. Secondly, the magnetic configuration has to be close to a double null (DN), leading to a reduction of the magnetic shear in the extreme vicinity of the separatrix. As a consequence, its stabilizing effect on ballooning modes is weakened.

Original languageEnglish
Article number086020
Number of pages13
JournalNuclear Fusion
Volume59
Issue number8
Early online date16 May 2019
DOIs
Publication statusPublished - 26 Jun 2019

Fingerprint

refueling
ballooning modes
flattening
plasma density
shear
profiles
configurations

Keywords

  • ballooning modes
  • grassy ELMs
  • H-mode
  • plasma triangularity
  • separatrix density
  • type-II ELMs

Cite this

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title = "Dependence on plasma shape and plasma fueling for small edge-localized mode regimes in TCV and ASDEX Upgrade",
abstract = "Within the EUROfusion MST1 work package, a series of experiments has been conducted on AUG and TCV devices to disentangle the role of plasma fueling and plasma shape for the onset of small ELM regimes. On both devices, small ELM regimes with high confinement are achieved if and only if two conditions are fulfilled at the same time. Firstly, the plasma density at the separatrix must be large enough (n e,sep/n G ∼ 0.3), leading to a pressure profile flattening at the separatrix, which stabilizes type-I ELMs. Secondly, the magnetic configuration has to be close to a double null (DN), leading to a reduction of the magnetic shear in the extreme vicinity of the separatrix. As a consequence, its stabilizing effect on ballooning modes is weakened.",
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Dependence on plasma shape and plasma fueling for small edge-localized mode regimes in TCV and ASDEX Upgrade. / Labit, B.; Eich, T.; Harrer, G.F.; Gahle, D.; Henderson, S.

In: Nuclear Fusion, Vol. 59, No. 8, 086020, 26.06.2019.

Research output: Contribution to journalArticle

TY - JOUR

T1 - Dependence on plasma shape and plasma fueling for small edge-localized mode regimes in TCV and ASDEX Upgrade

AU - Labit, B.

AU - Eich, T.

AU - Harrer, G.F.

AU - Gahle, D.

AU - Henderson, S.

N1 - This research article is authored by numerous individuals. Please consult the manuscript for full attribution details.

PY - 2019/6/26

Y1 - 2019/6/26

N2 - Within the EUROfusion MST1 work package, a series of experiments has been conducted on AUG and TCV devices to disentangle the role of plasma fueling and plasma shape for the onset of small ELM regimes. On both devices, small ELM regimes with high confinement are achieved if and only if two conditions are fulfilled at the same time. Firstly, the plasma density at the separatrix must be large enough (n e,sep/n G ∼ 0.3), leading to a pressure profile flattening at the separatrix, which stabilizes type-I ELMs. Secondly, the magnetic configuration has to be close to a double null (DN), leading to a reduction of the magnetic shear in the extreme vicinity of the separatrix. As a consequence, its stabilizing effect on ballooning modes is weakened.

AB - Within the EUROfusion MST1 work package, a series of experiments has been conducted on AUG and TCV devices to disentangle the role of plasma fueling and plasma shape for the onset of small ELM regimes. On both devices, small ELM regimes with high confinement are achieved if and only if two conditions are fulfilled at the same time. Firstly, the plasma density at the separatrix must be large enough (n e,sep/n G ∼ 0.3), leading to a pressure profile flattening at the separatrix, which stabilizes type-I ELMs. Secondly, the magnetic configuration has to be close to a double null (DN), leading to a reduction of the magnetic shear in the extreme vicinity of the separatrix. As a consequence, its stabilizing effect on ballooning modes is weakened.

KW - ballooning modes

KW - grassy ELMs

KW - H-mode

KW - plasma triangularity

KW - separatrix density

KW - type-II ELMs

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DO - 10.1088/1741-4326/ab2211

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JO - Nuclear Fusion

JF - Nuclear Fusion

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