A. R. Field P. Carvalho L. Garzotti E. Lerche C. Maggi F. Rimini C. Roach S. Saarelma M. Sertoli JET contributors
In high-performance, ITER baseline-scenario pulses (3MA/2.7T) in JET-ILW with high levels (~ 32 MW) of heating power, typically ~ 20-40% of the input power is radiated, predominantly by W impurities, which are sputtered from the divertor targets and reach the confined plasma. Sustained ELMy H-mode operation at such high heating power in JET-ILW req…
Preprint PublishedA. R. Field L. Frassinetti C. Maggi S. Saarelma JET contributors
Empirically-based power-balance calculations of the inter-ELM separatrix loss power are presented for JET pulses with both the carbon- (JET-C) and ITER-like (JET-ILW) walls, to facilitate comparisons with results of on-going, non-linear gyro-kinetic calculations of pedestal heat transport, e.g. as reported in [1]. These might be able to explain the…
PreprintL. 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 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 pres…
Preprint PublishedJ. P. Martin-Collar B. F. McMillan S. Saarelma A. Bottino
We perform a study of system-scale to gyro-radius scale electromagnetic modes in a pedestal-like equilibrium using a gyrokinetic code ORB5, and compare to the results of a local gyrokinetic code, GS2, and an MHD energy principle code, MISHKA. In the relevant large-system, short wavelength regime, good agreement between the gyrokinetic codes is foun…
Preprint PublishedD A Ryan M Dunne A Kirk S Saarelma W Suttrop C Ham Y Q Liu M Willensdorfer the ASDEX Upgrade team the MST1 team
A numerical survey of the plasma response in ASDEX Upgrade ELM control experiments is conducted, to clarify the role of triangularity in the suppression mechanism. The pedestal pressure increases with triangularity consistent with previous work [2], which modestly boosts the peeling response. However, the peeling response decreases with increasi…
Preprint PublishedL. Horvath C.F. Maggi F.J. Casson V. Parail L. Frassinetti F. Koechl S. Saarelma M.G. Dunne K.J. Gibson JET Contributors
Recent studies have shown that on JET with the Be/W ITER-like wall (JET-ILW) in high beta discharges with high D2 gas rates the inter-ELM temperature pedestal growth is saturated half way through the ELM cycle, leading to plasmas with reduced confinement, and that the linear MHD stability of these pedestals is inconsistent with the Peeling-Ballooni…
Preprint PublishedL. Garzotti E. Barbato J. Garcia N. Hayashi G.Giruzzi P. Maget M. Romanelli S. Saarelma R. Stankiewitz M. Yoshida I. Voitsekhovitch R. Zagórski
Reference scenarios for the JT-60SA tokamak have been simulated with one-dimensional transport codes to assess the stationary state of the flat-top phase and provide a profile database for further physics studies (e.g. MHD stability, gyrokinetic analysis) and diagnostics design. The types of scenario considered vary from pulsed standard H-mode to a…
Preprint PublishedS.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 PublishedS. Pamela T. Eich L. Frassinetti B. Sieglin S. Saarelma G. Huijsmans M. Hoelzl M. Becoulet F. Orain S. Devaux I. Chapman I. Lupelli E. Solano JET Contributors
A subset of JET ITER-like wall (ILW) discharges, combining electron density and temperature as well as divertor heat flux measurements, has been collected for the validation of non-linear MHD simulations of Edge-Localised-Modes (ELMs). This permits a quantitative comparison of simulation results against experiments, which is required for the valida…
Preprint PublishedJ.C. Hillesheim D. Dickinson C.M. Roach S. Saarelma R. Scannell A. Kirk N.A. Crocker W.A. Peebles H. Meyer The MAST Team
Measurements of local density and magnetic field fluctuations near the pedestal top, conditionally-averaged over the ELM cycle, have been made in MAST. A Doppler backscattering (DBS) system installed at MAST was used to measure intermediate-k (k ? _i _ 3 - 4) density fluctuations at the top of the pedestal. A novel diagnostic technique combining DB…
Preprint Published