F. Militello Y. Liu
Intrinsic Scrape Off Layer (SOL) instabilities are studied using flute approximation and incorporating the appropriate sheath boundary conditions at the target. The linear growth rate and the structure of the modes are obtained. The associated diffusion is estimated using a ?/k2? approach for the fastest growing modes. The model used includes curva…
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.D. Lawson M. Groth P. Belo S. Brezinsek G. Corrigan A. Czarnecka E. Delabie P. Drewelow D. Harting I. KsiaSek C.F. Maggi C. Marchetto A.G. Meigs S. Menmuir M.F. Stamp S. Wiesen JET-EFDA Contributors
A discrepancy in the divertor radiated powers between EDGE2D-EIRENE simulations, both with and without drifts, and JET-ILW experiments employing a set of NBI-heated L-mode discharges with step-wise density variation is investigated. Results from a VUV/visible poloidally scanning spectrometer are used together with bolometric measurements to determi…
Preprint PublishedV.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 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 PublishedS. Zhen T.N. Todd
The existing tritium resource available for future fusion power plant D-T operation is severely limited. It is essential to breed tritium to maintain the continuous consumption in the D-T plasma so as to sustain the required fusion power. A minimum criterion of calculated tritium breeding ratio (TBR) >1.1 is adopted to ensure tritium self-sufficien…
Preprint PublishedJ. Morris R. Kemp M. Kovari J. Last P. Knight
Power plant studies using systems codes allow the optimisation of designs to maximise or minimise some figure of merit: fusion power gain or cost of electricity, for example. The code should trade off between parameters to find the optimum whilst producing a solution consistent with physics and technology limitations. This paper describes the recen…
Preprint PublishedS. C. Chapman R. O. Dendy T. N. Todd N. W. Watkins F. A. Calderon J. Morris JET Contributors
A global signature of the build-up to an intrinsic edge localized mode (ELM) is found in the temporal analytic phase of signals measured in full flux azimuthal loops in the divertor region of JET. Toroidally integrating, full flux loop signals provide a global measurement proportional to the voltage induced by changes in poloidal magnetic flux; the…
PublishedD. Rendell S.R. Shaw P.J. Pool C. Oberlin-Harris JET EFDA Contributors
The JET flywheel generator converters have operated since 1983 and for over 85,000 pulses. Problems with this plant are discussed, including corrosion, unbalanced flow and arcing within the liquid resistors; starting difficulties on both machines; and failure of the plug-braking transformers at energisiation. In 2012/13 two sets of thrust bearing p…
Preprint PublishedV.F. Shevchenko Y.F. Baranov T. Bigelow J.B. Caughman S. Diem C. Dukes P. Finburg J. Hawes C. Gurl J.Griffiths J. Mailloux M. Peng A.N. Saveliev Y. TakaHe H. Tanaka G. Taylor
Start-up technique reported here relies on a double mode conversion (MC) for electron Bernstein wave (EBW) excitation. It consists of MC of the ordinary (0) mode, entering the plasma from the low field side of the tokamak, into the extraordinary (X) mode at a mirror-polarizer located at the high field side. The X mode propagates back to the plasma,…
Preprint Published