Showing 1 - 10 of 28 Journals Results
2020
UKAEA-CCFE-PR(20)21
J F Parisi F I Parra C M Roach C Giroud W Dorland D R Hatch M Barnes J C Hillesheim N Aiba J R Ball P G Ivanov
Local linear gyrokinetic simulations show that electron temperature gradient (ETG) instabilities are the fastest growing modes for kyρi >~ 0.1 in the steep gradient region for a JET pedestal discharge (92174) where the electron temperature gradient is steeper than the ion temperature gradient. Here, ky is the wa…
Preprint Purchase2019
UKAEA-CCFE-PR(19)62
L. Horvath C.F. Maggi A. Chankin S. Saarelma A.R. Field E. Belonohy A. Boboc G. Corrigan E.G. Delabie J. Flanagan L. Frassinetti C. Giroud D. Harting D. Keeling D. King M. Maslov G.F. Matthews S. Menmuir S.A. Silburn J. Simpson A.C.C Sips H. Weisen K.J. Gibson and JET Contributors
The pedestal structure, ELM losses and linear MHD stability are analysed in a series of JET-ILW H and D type I ELMy H-mode plasmas. The pedestal pressure (pPED) is typically higher in D than in H at the same input power, with the difference mainly due to lower density in H than in D. At the same input power, the pedestal electron pressur…
Preprint Purchase2019
UKAEA-CCFE-PR(19)25
Martin Valovic Y Baranov G Buchanan J Citrin E Delabie L Frassinetti J M Fontdecaba L Garzotti C Giroud R McKean E Lerche V Kiptily F Köchl M Marin M Maslov S Menmuir G Tvalashvili H Weisen the JET Contributors
Deuterium pellets are injected into initially pure hydrogen H-mode plasma in order to control H:D isotope mixture. The pellets are deposited in outer 20% of minor radius, similar to that expected in ITER creating transiently hollow electron density profiles. The isotope mixture of H:D ~ 45:55% is obtained in the core with pellet fuelling throughput…
Preprint Published2019
UKAEA-CCFE-PR(19)21
Luca Garzotti C. Challis R. Dumont D. Frigione J. Graves E Lerche J. Mailloux M. Mantsinen F. Rimini F. Casson A. Czarnecka J. Eriksson R. Felton L. Frassinetti D. Gallart J. Garcia C. Giroud E. Joffrin H.-T. Kim N. Krawczyk M. Lennholm P. Lomas C. Lowry L. Meneses I. Nunes C. M. Roach M. Romanelli S. Sharapov S. Silburn A. Sips E. Stefanikova M. Tsalas D. Valcarcel M. Valovic JET contributors
The JET exploitation plan foresees D-T operations in 2020 (DTE2). With respect to the first D-T campaign in 1997 (DTE1), when JET was equipped with a carbon wall, the experiments will be conducted in presence of a beryllium-tungsten ITER-like wall (ILW) and will benefit from an extended and improved set of diagnostics and higher additional heating …
Preprint Published2018
UKAEA-CCFE-PR(19)07
M. Carr A. Meakins S. Silburn J. Karhunen M. Bernert C. Bowman A. Callarelli P. Carvalho C. Giroud J. Harrison S. Henderson A. Huber B. Lipschultz T. Lunt D. Moulton F. Reimold ASDEX Upgrade team JET contributors MAST-Upgrade team the EUROfusion MST1 Team
Ray-tracing techniques are applied to divertor filtered imaging, a diagnostic that has long been plagued by polluting reflected light features in metal walled fusion machines. A physically realistic surface reflection model is developed from a Cook-Torrence microfacet BRDF model. Camera calibration images of in-vessel point lights at JET are use…
Preprint Published2018
UKAEA-CCFE-PR(18)23
M. Carr A. Meakins M. Bernert P. David C. Giroud J. Harrison S. Henderson B. Lipschultz F. Reimold the EUROfusion MST1 Team ASDEX Upgrade team
Ray-tracing techniques are applied to bolometry, a diagnostic particularly sensitive to machine geometry due to the effect of volume sampling. Sightlines from the ASDEX-Upgrade bolometer foils were ray-traced with a path tracing algorithm, where the optical path is represented by a statistical bundle of ray paths connecting the foil surface with th…
Preprint Published2018
UKAEA-CCFE-PR(18)15
M. Maslov D. King E. Viezzer D. Keeling C. Giroud T. Tala A. Salmi M. Marin J. Citrin C. Bourdelle E. Solano JET contributors
Particle transport is of a great importance for understanding physics of tokamak plasmas and planning future experiments on larger machines such as ITER. The subject was intensively studied in the past, particularly in relation to density peaking and presence of anomalous inward particle convection in L- and H-mode. While in the L-mode case presenc…
Preprint Published2017
CCFE-PR(17)13
S.Pamela G.Huijsmans T.Eich S.Saarelma I.Lupelli C.Maggi C.Giroud I.Chapman S.F.Smith L.Frassinetti M.Becoulet M.Hoelzl F.Orain S.Futatani JET Contributors
Future devices like JT-60SA, ITER and DEMO require quantitative predictions of pedestal density and temperature levels, as well as inter-ELM and ELM divertor heat fluxes, in order to improve global confinement capabilities while preventing divertor erosion/melting in the planning of future experiments. Such predictions can be obtained from dedicate…
Preprint Published2017
CCFE-PR(17)42
P. Manas Y. Camenen S. Benkadda H. Weisen C. Angioni F.J. Casson C. Giroud M. Gelfusa M. Maslov JET contributors
Quantitative comparisons are presented between gyrokinetic simulations and experimental values of the carbon impurity peaking factor in a database of JET H-modes during the carbon wall era. These plasmas feature strong NBI heating, hence high values of toroidal rotation and correponding gradient. Furthermore, the carbon profiles present particularl…
Preprint Published2016