Showing 1 - 10 of 127 Journals Results
2020
UKAEA-CCFE-PR(20)83
R.A. Tinguely P.G. Puglia N. Fil S. Dowson M. Porkolab A. Fasoli D. Testa JET Contributors*
This paper presents results of extensive analysis of mode excitation observed during the operation of the Alfvén Eigenmode Active Diagnostic (AEAD) in the JET tokamak during the 2019-2020 deuterium campaign. Six of eight toroidally-spaced antennas, each with independent power and phasing, were successful in actively exciting stable MHD modes in 47…
Preprint2020
UKAEA-CCFE-PR(20)75
V. Aslanyan S. Taimourzadeh L. Shi Z. Lin G. Dong P. Puglia M. Porkolab R. Dumont S. E. Sharapov J. Mailloux M. Tsalas M. Maslov A. Whitehead R. Scannell S. Gerasimov S. Dorling S. Dowson H. K. Sheikh T. Blackman G. Jones A. Goodyear K. K. Kirov P. Blanchard A. Fasoli D. Testa JET Contributors
The Gyrokinetic Toroidal Code (GTC) has been used to study Toroidal Alfven Eigenmodes (TAEs) in high-
performance plasmas. Experiments performed at the Joint European Torus, where TAEs were driven by
energetic particles arising from Neutral Beams, ion cyclotron resonant heating and resonantly excited by
2020
UKAEA-CCFE-PR(20)64
D. Iglesias W. Arter I. Balboa P. Bunting C. Challis J.W. Coenen Y. Corre S. Esquembri S. Jachmich K. Krieger G.F. Matthews R.A. Pittsh V. Riccardo M.L. Richiusa M. Porton F. Rimini S. Silburn V.K. Thompson R. Otin D. Valcarcel L. Vitton-Mea Z. Vizvary J. Williams JET contributors
The JET outboard divertor targets are the in-vessel components which receive the largest heat flux density. Surface delamination, radial cracks, and tie rod failures have been observed in the outboard tungsten-coated CFC tiles, while bulk tungsten special lamellas were intentionally melted in dedicated experiments. These different types of damag…
Preprint2020
UKAEA-CCFE-PR(20)17
M Marin J Citrin C Bourdelle Y Camenen F J Casson A Ho F Koechl M Maslov JET Contributors
Abstract. Core turbulent particle transport with multiple isotopes can display observable differences in behaviour between the electron and ion particle channels. Experimental observations at JET with mixed H-D plasmas and varying NBI and gas-puff sources [M. Maslov et al., Nucl. Fusion 7 076022 (2018)] inferred source dominated electron pea…
Preprint Purchase2020
UKAEA-CCFE-PR(20)08
C.D. Challis S. Brezinsek I. Coffey M. Fontana N. Hawkes D. Keeling D. King G. Pucella E. Viezzer JET Contributors
The initial current ramp phase of JET hybrid plasmas is used to optimise the target q-profile for main heating to allow access to high beta and avoid MHD instabilities. Mixed protium-deuterium experiments, carried out at JET since the installation of the beryllium-tungsten wall, have shown that the q-profile evolution during this Ohmic phase varies…
Preprint2019
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…
Preprint2019
UKAEA-CCFE-PR(19)52
M. Maslov A. Boboc M. Brix J. Flanagan M. Romanelli C. Price JET contributors
This work describes the behaviour of the global energy and particle confinement on JET observed in a massive database of H-mode plasmas covering almost whole lifetime of JET operations, both with carbon and metal wall. The analysis is focused on type I ELMy H-modes in stationary phases. It is shown that plasma density in that regime is determined m…
Preprint Purchase2019
UKAEA-CCFE-PR(19)49
A V Chankin G Corrigan C F Maggi JET Contributors
EDGE2D-EIRENE (the ‘code’) simulations show that radial electric field, Er, in the near scrape-off layer (SOL) of tokamaks can have large variations leading to a strong local E´B shear greatly exceeding that in the core region. This was pointed out in simulations of JET plasmas with varying divertor geometry, where the magnetic conf…
Preprint Published2019
UKAEA-CCFE-PR(19)30
H. J. C. Oliver S. E. Sharapov B. N. Breizman A. K. Fontanilla D. A. Spong D. Terranova JET Contributors
Alfven eigenmodes driven by energetic particles are routinely observed in tokamak plasmas. These modes consist of poloidal harmonics of shear Alfven waves coupled by inhomogeneity in the magnetic field. Further coupling is introduced by 3D inhomogeneities in the ion density during the assimilation of injected pellets. This additional coupling modi…
Preprint Purchase2019
UKAEA-CCFE-PR(19)25