J. C. Flanagan M. Sertoli M. Bacharis G. F. Matthews P. C. de Vries A. Widdowson I. H. Coffey G. Arnoux B. Sieglin S. Brezinsek J. W. Coenen S. Marsen T. Craciunescu A. Murari D. Harting A. Cackett E. Hodille JET-EFDA Contributors
Recent studies dedicated to the characterisation of in-vessel dust in JET with the new ITER-like wall (ILW) show that dust levels are orders of magnitude lower compared with the latter stages of the carbon-wall (CW) period and are decreasing with operational time. Less than 1 g of dust was recovered in a recent inspection, compared with more than 2…
Preprint 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 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 PublishedA.Baron-Wiechec A.Widdowson E.Alves C.F.Ayres N. P. Barradas S.Brezinsek J.P.Coad N.Catarino K.Heinola J.Likonen G.F.Matthews M.Mayer P. Petersson M.Rubel W. van Renterghem I. Uytdenhouwen JET-EFDA contributors
A set of Be and W tiles removed after the first ITER-like Wall campaigns (JET-ILW) from 2011-2012 has been analysed. The results indicate that the primary erosion site is in the main chamber (Be) as in previous carbon campaigns (JET-C). In particular the limiters tiles near the mid-plane are eroded probably during the limiter phases of discharges. …
Preprint PublishedK. Heinola A. Widdowson J. Likonen E. Alves A. Baron-Wiechec N. Barradas S. Brezinsek N. Catarino P. Coad S. Koivuranta G.F. Matthews M. Mayer P. Petersson JET-EFDA Contributors
Selected Ion Beam Analysis techniques applicable for detecting deuterium and heavier impurities have been used in the post-mortem analyses of tiles removed after the first JET ITER-Like Wall (JET-ILW) campaign. Over half of the retained fuel was measured in the divertor region. The highest figures for fuel retention were obtained from regions with …
Preprint PublishedJ. Beal A. Widdowson K. Heinola A. Baron-Wiechec K. J. Gibson J. P. Coad E. Alves B. Lipschultz A. Kirschner G. F. Matthews S. Brezinsek JET-EFDA Contributors
Rotating collectors are used in JET to provide time-resolved measurements of erosion and redeposition of vessel materials. The silicon collecting disks rotate behind an aperture, driven by pulsing of the toroidal magnetic field, with the deposits analysed ex-situ by Nuclear Reaction Analysis. The angular dependence of deposition is mapped to discha…
Preprint PublishedV. Riccardo G. Arnoux S. Collins P. Lomas G. Matthews N. Pace V. Thompson JET EFDA Contributors
The JET ITER-like Wall (ILW) provides the same plasma facing component configuration as ITER during its active phase: beryllium in the main chamber and tungsten in the divertor. Moving from a carbon-based wall to an all metal wall requires some operational adjustment. The reduction in radiation at the plasma edge and in the divertor can lead to hig…
PublishedP. C. De Vries M. Baruzzo G. M. D. Hogeweij S. Jachmich E. Joffrin P. J. Lomas G. F. Matthews A. Murari I. Nunes T. Pütterich C. Reux J. Vega JET-EFDA Contributors
In order to preserve the integrity of large tokamaks such as ITER, the number of disruptions has to be limited. JET has operated previously with a low frequency of disruptions (i.e., disruption rate) of 3.4% [P. C. de Vries et al., Nucl. Fusion 51, 053018 (2011)]. The start of operations with the new full-metal ITER-like wall at JET showed a marked…
PublishedJ.P. Coad E. Alves N.P. Barradas A. Baron-Wiechec K. Heinola J. Likonen M. Mayer G.F. Matthews P. Petersson A. Widdowson JET-EFDA Contributors
This paper reports on the first post-mortem analyses of tiles removed from JET after the first campaigns with the ITER-like Wall (ILW) during 2011-2 [1]. Tiles from the divertor have been analysed by the Ion Beam Analysis (IBA) techniques Rutherford Backscattering Spectroscopy (RBS) and Nuclear Reaction Analysis (NRA) and by Secondary Ion Mass Spec…
PublishedG. Arnoux I. Balboa M. Clever S. Devaux P. De Vries T. Eich M. Firdaouss S. Jachmich M. Lehnen P.J. Lomas G.F. Matthews Ph. Mertens I. Nunes V. Riccardo C. Ruset B. Sieglin D.F. Valcarcel J. Wilson K.-D. Zastrow JET-EFDA Contributors
The ITER-like wall (ILW) at JET is a unique opportunity to study the combination of material (beryllium and tungsten) that will be used for the plasma facing components (PFC) in ITER. Both the limiters (Be) and divertor (CFC W coated and bulk W) have been designed to maximise their power handling capability. During the last experimental campaign (O…
Published