Excitation Mechanism of Low-n Edge Harmonic Oscillations in Edge Localized Mode-Free, High Performance, Tokamak Plasmas.
Phys Rev Lett
; 122(15): 155003, 2019 Apr 19.
Article
em En
| MEDLINE
| ID: mdl-31050499
ABSTRACT
The excitation mechanism for low-n edge harmonic oscillations in quiescent H-mode regimes is identified analytically. We show that the combined effect of diamagnetic and poloidal magnetohydrodynamic flows, with the constraint of a Doppler-like effect of the ion flow, leads to the stabilization of short wavelength modes, allowing low-n perturbation to grow. The analysis, performed in tokamak toroidal geometry, includes the effects of large edge pressure gradients, associated with the local flattening of the safety factor and diamagnetic flows, sheared parallel and E×B rotation, and a vacuum region between plasma and the ideal metallic wall. The separatrix also is modeled analytically.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Tipo de estudo:
Prognostic_studies
Idioma:
En
Revista:
Phys Rev Lett
Ano de publicação:
2019
Tipo de documento:
Article
País de afiliação:
Itália