Showing 1 - 10 of 24 Journals Results
2019
UKAEA-CCFE-PR(20)18
M Valovič P T Lang A Kirk W Suttrop A Bock P J Mc Carthy M Faitsch B Plöckl2 the ASDEX Upgrade team the EUROfusion MST1 team
It is demonstrated that tokamak plasma can be fuelled by pellets while simultaneously maintaining ELM suppression by external resonant magnetic perturbations (RMPs). Pellets are injected from vertical high field site and deposited at outer part of plasma cross section. Each pellet triggers benign MHD event followed by short lived ELM free phase. Th…
Preprint Published2019
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(18)22
L. Garzotti P. Belo G. Corrigan D. Harting F. Köchl A. Loarte E. Militello Asp V. Parail R.Ambrosino M. Cavinato M. Mattei M. Romanelli R. Sartori M. Valovič
The operation of a tokamak designed to test the sustainability of a thermonuclear grade plasma like the International Tokamak Experimental Reactor (ITER) presents several challenges. Among them is the necessity of fuelling the plasma to reach the density required to generate enough fusion power to achieve Q = 10 and, at the same time, to protect th…
Preprint Published2016
CCFE-PR(16)09
M. Valovič P.T. Lang A. Kirk W. Suttrop M. Cavedon G. Cseh M. Dunne L.R. Fischer L. Garzotti L. Guimarais G. Kocsis A. Mlynek B. Plőckl R. Scannell T. Szepesi G. Tardini A. Thornton E. Viezzer E. Wolfrum The ASDEX Upgrade team The EUROfusion MST1 team
The complete refuelling of the plasma density loss (pump-out) caused by mitigation of Edge Localised Modes (ELMs) is demonstrated on the ASDEX Upgrade tokamak. The plasma is refuelled by injection of frozen deuterium pellets and ELMs are mitigated by external resonant magnetic perturbations (RMPs). In this experiment relevant dimensionless paramete…
Preprint Published2015
CCFE-PR(15)11
A. Kirk W. Suttrop I.T. Chapman Yueqiang Liu R. Scannell A.J. Thornton L. Barrera Orte P. Cahyna T. Eich R. Fischer C. Fuchs C. Ham J.R. Harrison MW. Jakubowski B. Kurzan S. Pamela M. Peterka D. Ryan S. Saarelma B. Sieglin M. Valovic M Willensdorfer MAST and ASDEX Upgrade Teams
Sustained Edge Localised Mode (ELM) mitigation has been achieved on MAST and AUG using RMPs with various toroidal mode numbers over a wide range of low to medium collisionality discharges. The ELM energy loss and peak heat loads at the divertor targets have been reduced. The ELM mitigation phase is typically associated with a drop in plasma density…
Preprint Published2015
CCFE-PR(15)03
M. Valovic L. Garzotti C. Gurl A. Kirk D. Dunai A.R. Field I. Lupelli G. Naylor A. Thornton The MAST Team
The fuelling of plasmas by shallow frozen pellets with simultaneous mitigation of edge- localised modes (ELM) by external magnetic perturbation is demonstrated on the MAST tokamak. In these plasmas post-pellet particle loss is dominated by ELMs. It is shown that the size of post-pellet ELMs can be controlled by external magnetic perturbations. Post…
Preprint Published2015
CCFE-PR(15)48
S. S. Henderson L. Garzotti F.J. Casson D. Dickinson M. O'Mullane A. Patel C.M. Roach H.P. Summers H. Tanabe M. Valovic MAST team
Carbon and nitrogen impurity transport coefficients are determined from gas puff experiments carried out during repeat L-mode discharges on the Mega-Amp Spherical Tokamak (MAST) and compared against a previous analysis of helium impurity transport on MAST. The impurity density profiles are measured on the lowfield side of the plasma, therefore this…
Preprint Published2014
S. S. Henderson L. Garzotti F. J. Casson D. Dickinson M. F. J. Fox M. O’Mullane A. Patel C. M. Roach H. P. Summers M. Valovic The Mast Team
Time-dependent helium gas puff experiments have been performed on the Mega Ampere Spherical Tokamak (MAST) during a two point plasma current scan in L-mode and a confinement scan at 900 kA. An evaluation of the He II spectrum line induced by charge exchange suggests anomalous rates of diffusion and inward convection in the outer regions of both L-m…
Published2014