H-mode access and performance in the Mega-Amp Spherical Tokamak

Autor: K.B. Axon, A. W. Morris, D. Ciric, R.J. Buttery, R. J. Akers, J.-W. Ahn, G. F. Counsell, S.J. Fielding, I. Lehane, A. Kirk, S.J. Manhood, T. Pinfold, S. Gee, B. Lloyd, M. J. Walsh, N. J. Conway, E. R. Arends, Nbi Team, A. Tabasso, S. Warder, Vladimir Shevchenko, L. Appel, M. P. S. Nightingale, Matthew Hole, M. Valovic, C. Ribeiro, M. Price, J. R. Watkins, Mikhail Gryaznevich, A. R. Field, S. Shibaev, M. A. McGrath, A. Sykes, Mast Team, Romualdo Martín, G. Cunningham, C. Byrom, Setthivoine You, D Taylor, H. F. Meyer, J. Dowling, G. McArdle, M. R. Tournianski, P. G. Carolan, H. R. Wilson
Rok vydání: 2002
Předmět:
Zdroj: Physics of Plasmas. 9:3919-3929
ISSN: 1089-7674
1070-664X
Popis: Spontaneous transitions from the low “L-mode” to high “H-mode” of tokamak plasma confinement, first observed during neutral beam heating experiments on ASDEX, are now routinely achieved in many tokamak experiments. The H-mode regime is attractive as it offers the possibility of enhanced confinement, and thus a route towards a more “compact” and cost-efficient fusion power-plant. Transition to H-mode is now routinely achievable in the Mega-Amp Spherical Tokamak (MAST) [A. C. Darke et al., Fusion Technology 1994 (Elsevier, Amsterdam, 1995), Vol. 1, p. 799] for both Ohmically and neutral beam injection (NBI) heated plasmas (PNBI∼0.5–1.7 MW). H-mode plasmas can be either center stack limited or X-point diverted, exhibiting regular Type III edge localized modes (ELMs). Global confinement in H-mode with low frequency ELMs is consistent with the international IPB(y,2) scaling and exceeds the scaling by a factor ∼1.5–2.0 for high performance discharges. Confinement degrades with increasing ELM frequency (which in...
Databáze: OpenAIRE