Results 211 to 220 of about 466 (242)

Divertor detachment and exhaust on the TdeV tokamak

Plasma Physics and Controlled Fusion, 1996
Experimental data, analysis and simulations are used to describe the physics of divertor detachment and He exhaust under detached conditions in TdeV. With increasing density, the plasma is found to detach progressively from the outboard divertor plates with a marked reduction of the ion flux to the plates, the generation of a pressure gradient between ...
R Décostebec, B L Stansfield, J L Gauvreau, G W Pacher, F Méo, G Abel, C Boucher, B C Gregorynergie, null Matériaux, J P Gunn, E Haddad, J-L Lachambre, J Mailloux, R Marchand, F Martin, N Richard, M M Shoucri, B Terreault, W Zuzak   +18 more
openaire   +1 more source

Operation space of divertor detachment in DEMO

2015 IEEE 26th Symposium on Fusion Engineering (SOFE), 2015
In the paper we consider the operation window of DEMO divertor detachment expected under DEMO I operation conditions for various external impurity levels, particle throughput and pumping conditions, envisaged for fusion reactor. The operation region is defined in terms of upstream heat flux and the upstream density and is bounded by the burn conditions
Igitkhanov, Y., Day, C., Varoutis, S., Hauer, V.   +3 more
openaire   +2 more sources

The role of divertor pumping in plasma detachment and particle exhaust in a closed divertor

Nuclear Fusion, 2020
Abstract The impact of pumping on divertor power dissipation and particle exhaust in a closed divertor with flat target configuration is examined using SOLPS modeling. A closed divertor can increase neutral pressure and enhance radiative dissipation; accordingly it has been proposed as a direction for the design of advanced divertors to ...
Chaofeng Sang, P.C. Stangeby, H.Y. Guo, Dezhen Wang   +3 more
openaire   +1 more source

Stability of the detachment front in a tokamak divertor

Journal of Nuclear Materials, 1999
Abstract Experimental observations show that when a divertor plasma detaches, radiation regions (fronts) move towards the X-point. This indicates that the localization of the fronts in the divertor is unstable. We study theoretically the stability of detached divertor operation and compare our results with experimental data. We show that the impurity
S.I. Krasheninnikov, M. Rensink, T.D. Rognlien, A.S. Kukushkin, J.A. Goetz, B. LaBombard, B. Lipschultz, J.L. Terry, M. Umansky   +8 more
openaire   +1 more source

Influence of Plasma Composition on Divertor Detachment

Contributions to Plasma Physics, 2000
The phenomena that lead to the observed power and particle flux detachment have been studied with the code B2-Eirene for DIII-D Helium and Deuterium experiments. Contrary to the usual Deuterium experiments, a significant reduction of the power load to the divertor is observed in Helium discharges while the ion flux remains high.
Loarte, A., Kukushkin, A., Porter, G., Hill, D., Watkins, J., Reiter, D., Coster, D., Schneider, R.   +7 more
openaire   +2 more sources

Access conditions for H modes with detached divertor plasmas

Nuclear Fusion, 1996
Access conditions for H modes with detached divertor plasmas are derived by considering power threshold, divertor plasma temperature and density limit constraints. It is found that there is a minimum scrape-off layer power and main plasma density for accessing the detached divertor H mode, and that the required divertor radiated power fraction must ...
Borrass, K., Farengo, R., Vlases, G.
openaire   +2 more sources

Detachment and divertor temperature and density redistribution

Physics of Plasmas, 2001
A theoretical model is developed for large scale-length, one-dimensional thermal instabilities along the field lines in tokamak divertors. Calculated growth rates predict a divertor thermal instability under the conditions (low-plasma temperature and density and high-neutral densities at the divertor plate) at which detachment followed by large-scale ...
openaire   +1 more source

Volume recombination and detachment in JET divertor plasmas

Journal of Nuclear Materials, 1999
The spatial distribution of recombination has been studied in the detaching phases of L and H-mode discharges. Recombination is detected by the sudden increase in intensity of the high quantum number states of the Balmer series of hydrogen. In L-mode, detachment occurs completely and the radiation moves to a region near the X-point.
R.D. Monk, A. Meigs, L. Horton, L.C. Ingesson, J. Lingertat, G.F. Matthews, M.G. O'Mullane, R. Prentice, M.F. Stamp, G.M. McCracken, P.C. Stangeby   +10 more
openaire   +1 more source

Effect of transport on MAR in detached divertor plasma

Journal of Nuclear Materials, 2003
Abstract The effect of H 2 transport on the onset of MAR in the relatively lower plasma parameter regime of a detached state ( n e =1×10 19 m −3 , T e =1 eV) is investigated theoretically. The vibrationally excited molecular densities and the degree of MAR are evaluated by using a 1-D Monte Carlo method (with transport effect), and by solving ...
Kenji Miyamoto, A. Hatayama, Y. Ishii, T. Miyamoto, A. Fukano   +4 more
openaire   +1 more source

The influence of molecular dynamics on divertor detachment in TCV

Contributions to Plasma Physics, 2004
AbstractIf vibrationally excited molecules are discretised into individual species and proper account is taken of the toroidal geometry in simulating neutrals, some improvement can be made in simulating the anomalous detachment behaviour seen at the outer target of TCV single‐null lower L‐mode discharges.
Wischmeier M, R A Pitts, A Alfier, Y Andrebe, R Behn, D Coster, J Horacek, P Nielsen, R Pasqualotto, D Reiter, A Zabolotsky   +10 more
openaire   +4 more sources