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 PublishedJames Harrison C. Theiler B. Lipschultz A. Perek R. Maurizio B. Linehan W. A. J. Vijvers B. P. Duval B. Labit U. Sheikh K. Verhaegh S. Henderson A. Karpushov O. Fevrier H. de Oliviera H. Reimerdes A. Merle X. Feng the TCV team and the EUROfusion MST1 team
Recent experiments on TCV have made significant progress toward partial detachment of the outer divertor in neutral beam heated H-mode plasmas. The heating power required to enter H-mode was measured in a range of divertor configurations, finding that, in the vicinity of the PL-H/ne curve, the threshold power is largely independent of the poloidal …
Preprint PublishedB D Dudson J Allen T Body B Chapman C Lau L Townley D Moulton J Harrison B Lipschultz
A new 1D divertor plasma code, SD1D, has been used to examine the role of recombination, radiation, and momentum exchange in detachment. Neither momentum or power losses by themselves are found to be sufficient to produce target ion flux rollover in detachment; radiative power losses are required to a) limit and reduce the ionization source and …
Preprint PublishedD. Moulton G. Corrigan J.R. Harrison B. Lipschultz JET Contributors
This paper further analyses the EDGE2D-EIRENE simulations presented by [Chankin et al (2017 Nucl. Mater. Energy 12 273], of L-mode JET plasmas in vertical-vertical (VV) and vertical-horizontal (VH) divertor configurations. As expected, the simulated outer divertor ionisation source peaks near the separatrix in VV …
Preprint PublishedM. 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 PublishedN. R. Walkden A. Wynn F. Militello B. Lipschultz G. Matthews C.Guillemaut J. Harrison D. Moulton JET Contributors
This paper presents the use of a novel modelling technique based around intermittent transport due to filament motion, to interpret experimental profile and fluctuation data in the scrape-off layer (SOL) of JET during the onset and evolution of a density profile shoulder. Three cases are studied at different points in a density ramp experiment wher…
Preprint PublishedN.R. Walkden A. Wynn F. Militello B. Lipschultz G. Matthews C.Guillemaut J. Harrison D. Moulton JET Contributors
Statistical analysis of the ion flux to the JET outer-wall is conducted in outer-wall limiter mounted Langmuir probe (OLP) time-series across a wide range of plasma current and line-averaged density during Ohmically heated horizontal target L-mode plasmas. The mean, _, and the standard deviation, _, of the ion-saturation current measured by the OLP…
Preprint PublishedA. R. Field I. Balboa P. Drewelow J. Flanagan C. Guillemaut J. R. Harrison A. Huber V. Huber B. Lipschultz G. Matthews A. Meigs J. Schmitz M. Stamp N. Walkden JET contributors
The dynamics and stability of divertor detachment in N2 seeded, type-I, ELMy H-mode plasmas with dominant NBI heating in the JET-ILW device is studied by means of an integrated analysis of diagnostic data from several systems, classifying data relative to the ELM times. It is thereby possible to study the response of the detachment evolution to the…
Preprint PublishedD. Moulton J. Harrison B. Lipschultz D. Coster
We show that a central characteristic of Super-X divertors, parallel area expansion fR (de ned as the ratio of the elementary area normal to the magnetic field at the target to that at the X-point, also known as total flux expansion), significantly changes the characteristics of the target plasma for fixed upstream conditions. To isolate the effect…
Preprint PublishedJ.R. Harrison W.A.J. Vijvers C. Theiler B.P. Duval S. Elmore B. Labit B. Lipschultz S.H.M. van Limpt S.W. Lisgo C.K. Tsui H. Reimerdes U. Sheikh K.H.A. Verhaegh M. Wischmeier The MST TCV Teams
Divertor detachment in the TCV tokamak has been investigated through experiments and modelling. Density ramp experiments were carried out in ohmic heated L-mode pulses with the ion B drift directed away from the primary X-point, similar to previous studies [pitts2001]. Before the roll-over in the ion current to the outer strike point, C III and D? …
Preprint Published