Steady state advanced scenarios at ASDEX Upgrade

Steady state advanced scenarios at ASDEX Upgrade,10.1088/0741-3335/44/12B/306,Plasma Physics and Controlled Fusion,A C C Sips,R Arslanbekov,C Atanasiu

Steady state advanced scenarios at ASDEX Upgrade   (Citations: 7)
BibTex | RIS | RefWorks Download
A C C Sips, R Arslanbekov, C Atanasiu, W Becker, G Becker, K Behler, K Behringer, A Bergmann, R Bilato, D Bolshukhin, K Borrass, B Braams
Recent experiments at ASDEX Upgrade have achieved advanced scenarios with high βN (>3) and confinement enhancement over ITER98(y, 2) scaling, HH98y2 = 1.1–1.5, in steady state. These discharges have been obtained in a modified divertor configuration for ASDEX Upgrade, allowing operation at higher triangularity, and with a changed neutral beam injection (NBI) system, for a more tangential, off-axis beam deposition. The figure of merit, βNHITER89-P, reaches up to 7.5 for several seconds in plasmas approaching stationary conditions. These advanced tokamak discharges have low magnetic shear in the centre, with q on-axis near 1, and edge safety factor, q95 in the range 3.3–4.5. This q-profile is sustained by the bootstrap current, NBI-driven current and fishbone activity in the core. The off-axis heating leads to a strong peaking of the density profile and impurity accumulation in the core. This can be avoided by adding some central heating from ion cyclotron resonance heating or electron cyclotron resonance heating, since the temperature profiles are stiff in this advanced scenario (no internal transport barrier). Using a combination of NBI and gas fuelling line, average densities up to 80–90% of the Greenwald density are achieved, maintaining good confinement. The best integrated results in terms of confinement, stability and ability to operate at high density are obtained in highly shaped configurations, near double null, with δ = 0.43. At the highest densities, a strong reduction of the edge localized mode activity similar to type II activity is observed, providing a steady power load on the divertor, in the range of 6 MW m−2, despite the high input power used (>10 MW).
Journal: Plasma Physics and Controlled Fusion - PLASMA PHYS CONTROL FUSION , vol. 44, no. 12B, pp. B69-B83, 2002
Cumulative Annual
View Publication
The following links allow you to view full publications. These links are maintained by other sources not affiliated with Microsoft Academic Search.
    • ...The existing experience [27] on ELMs also suggests that FIRE’s double-null operation, high triangularity, and high edge density help reduce the size of ELMs with a transition to Type II ELMs...

    D. M. Meadeet al. Exploration of Burning Plasmas in FIRE

Sort by: