| Autor: |
Manz, P., Happel, T., Stroth, U., Eich, T., Silvagni, D., team, the ASDEX Upgrade |
| Předmět: |
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| Zdroj: |
Nuclear Fusion; Sep2020, Vol. 60 Issue 9, p1-10, 10p |
| Abstrakt: |
The I-mode is an attractive confinement regime for future tokamak based fusion reactors. A model is presented which explains the I-mode regime by the reduction of ITG turbulence near the separatrix at low collisionality, where the separatrix ion temperature can exceed the electron temperature. Drift-Alfvén-turbulence develops, with large and small-scale fluctuations being suppressed by phase randomization and finite-Larmor-radius effects, respectively. The intermediate scales form a broad peak in the frequency spectrum, which features the same properties as the characteristic weakly coherent mode. The model, which is studied by means of gyro-fluid simulations, reproduces a number of other experimental I-mode observations, such as decoupled energy and particle transport, intermittent turbulent bursts with precursors, an operational window widening with magnetic field strength, and the challenges met when detaching the plasma. [ABSTRACT FROM AUTHOR] |
| Databáze: |
Complementary Index |
| Externí odkaz: |
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