V.G. Kiptily
Comparing with ITER, the experimental fusion machine under constraction, the next step test fusion power plant, DEMO will be characterized by very long pulse/steady-state operation and much higher plasma volume and fusion power. The substantially increased level of neutron and gamma fluxes will require reducing the physical access to the plant. It …
Preprint PublishedC.D. Challis J. Garcia M. Beurskens P. Buratti E. Delabie P. Drewelow L. Frassinetti C. Giroud N. Hawkes J. Hobirk E. Joffrin D. Keeling D.B. King C.F. Maggi J. Mailloux C. Marchetto D. McDonald I. Nunes G. Pucella S. Saarelma J. Simps
The replacement of the JET carbon wall (C-wall) by a Be/W ITER-like wall (ILW) has affected the plasma energy confinement. To investigate this, experiments have been performed with both the C-wall and ILW to vary the heating power over a wide range for plasmas with different shapes. It was found that the power degradation of thermal energy confinem…
Preprint PublishedK. G. McClements R. J. Akers W.U. Boeglin M. Cecconello D. Keeling O.M. Jones A. Kirk I. Klimek R.V. Perez K. Shinohara K. Tani
The effects of resonant magnetic perturbations (RMPs) on the confinement of energetic (neutral beam) ions in the Mega Amp Spherical Tokamak (MAST) are assessed experimentally using measurements of neutrons, fusion protons and fast ion D _ (FIDA) light emission. In single null-diverted (SND) MAST pulses with relatively low plasma current (400 kA), t…
Preprint PublishedJ. C. Hillesheim E. Delabie H. Meyer C. F. Maggi L. Meneses E. Poli JET Contributors
High spatial resolution Doppler backscattering measurements in JET have enabled new insights into the development of the edge . We observe fine-scale spatial structures in the edge well with a wave number kr ? i ˜ 0.4–0.8, consistent with stationary zonal flows, the characteristics of which vary with density. The zonal flow amplitude and wavelen…
Preprint PublishedJ. R. Nicholas P. Ireland D. Hancock D. Robertson
A low temperature jet impingement based heat sink module has been developed for potential application in a near-term fusion power plant divertor. The design is composed of a number of hexagonal CuCrZrsheets bonded together in a stack to form a laminate structure. This method allows the production ofcomplex flow paths using relatively simple manufac…
PublishedE.Peluso M.Gelfusa A.Murari I.Lupelli P.Gaudio
The H mode of confinement in Tokamaks is characterized by a thin region of high gradients, located at the edge of the plasma and called the Edge Transport Barrier. Even if various theoretical models have been proposed for the interpretation of the edge physics, the main empirical scaling laws of the plasma confinement time are expressed in terms of…
PublishedU. Kruezi S. Jachmich H.R. Koslowski M. Lehnen S. Brezinsek G. Matthews JET EFDA Contributors
Disruptions, the fast accidental losses of plasma current and stored energy in tokamaks, represent asignificant risk to the mechanical structure as well as the plasma facing components of reactor-scale fusion facilities like ITER. At JET, the tokamak experiment closest to ITER in terms of operating parameters and size, massive gas injection has bee…
Preprint PublishedJ. Milnes N.B. Ayed F. Dhalla G. Fishpool J. Hill I. Katramados R. Martin G. Naylor T. O’Gorman R. Scannell The MAST Upgrade team
The Mega Amp Spherical Tokamak (MAST) is the centre piece of the UK fusion research programme.In 2010, a MAST Upgrade programme was initiated with three primary objectives, to contribute to: (1)testing reactor concepts (in particular exhaust solutions via a flexible divertor allowing Super-X and otherextended leg configurations); (2) adding to the …
Preprint PublishedE. Havlickova M. Wischmeier B. Lipschultz G. Fishpool
An impurity seeding scan has been simulated in three different divertor configurations of MAST-U, showing the effect of the divertor geometry on the transition to detachment. The three configurations include a conventional short divertor, a Super-X divertorwith large poloidal flux expansion and a Super-X divertor with small poloidal flux expansion.…
Preprint PublishedE. Lerche M. Goniche P. Jacquet D. Van Eester V. Bobkov L. Colas A. Czarnecka S. Brezinsek M.Brix K. Crombe M. Graham M. Groth I. Monakhov T. Mathurin G. Matthews L. Meneses C. Noble V. Petrzilka F. Rimini A. Shaw JET-EFDA Contributors
Recent JET-ILW [1,2] experiments reiterated the importance of tuning the plasma fuelling in order to optimize ion cyclotron resonance frequency (ICRF) heating in high power H-mode discharges. By fuelling the plasma from gas injection modules (GIMs) located in the midplane and on the top of the machine instead of adopting the more standardly used di…
Preprint Published