L. Howlett I. Cziegler S. Freethy H. Meyer
A comprehensive L-H power threshold study of MAST data is presented, with a detailed categorisation of transition and intermediate behaviour and a comparison of the results to scaling laws. Preliminary studies into the ion and electron heat flux for transitions at different densities are introduced. The first results of an L-H transition study o…
PreprintG. Giruzzi M. Fontana F.P. Orsitto E. de la Luna R. Dumont L. Figini M. Maslov S. Mazzi S. Schmuck L. Senni C. Sozzi C. Challis D. Frigione J. Garcia L. Garzotti J. Hobirk A. Kappatou D. Keeling E. Lerche C. Maggi J. Mailloux F. Rimini D. Van Eester JET contributors
Recent experiments performed in JET at high level of plasma heating, in preparation of, and during the DT campaign have shown significant discrepancies between electron temperature measurements by Thomson Scattering (TS) and Electron Cyclotron Emission (ECE). In order to perform a systematic analysis of this effect, a simple model of bipolar dis…
PreprintM. Kryjak B. Dudson D. Power S. Mijin C. Ridgers
The study of plasma exhaust remains a core focus of current efforts towards viable DEMO-class magnetically confined fusion devices. The scrape-off layer (SOL) features complex physics. This is especially true for detachment, a mechanism where a cloud of neutrals forms at the divertor target and becomes a sink of plasma energy, momentum and part…
PreprintB. Chapman D.R. Hatch A.R. Field L. Frassinetti J.C. Hillesheim L. Horvath C.F. Maggi J. F. Parisi C.M. Roach S.Saarelma J. Walker JET contributors
We present the results of GENE gyrokinetic calculations based on a series of JET-ILW type I ELMy H-mode discharges operating with similar experimental inputsbut at different levels of power and gas fuelling. We show that turbulence due to slab electron-temperature-gradient modes (sETGs) produces a significant amount of heat flux in four JET-ILW …
PublishedA. Ho J. Citrin C. D. Challis C. Bourdelle F. J. Casson J. Hobirk A. Kappatou F. Koechl E. Lerche
This work applies the coupled JINTRAC and QuaLiKiz-neural-network (QLKNN) model on the ohmic current ramp-up phase of a JET D discharge. The chosen scenario exhibits a hollow Te profile attributed to core impurity accumulation, which is observed to worsen with the increasing fuel ion mass from D to T. A dynamic D simulation was validated, evolvi…
PreprintK K Kirov F. Auriemma R. Bilato C. Challis E. De la Luna J. Garcia J. Hobirk P. Jacquet A. Kappatou Y. Kazakov D. Keeling D. King V. Kiptily E. Lerche C. Maggi J. Mailloux P. Mantica M. Mantsinen M. Maslov R. Sharma Z. Stancar D. Van Eester JET-EFDA contributors
Several Ion Cyclotron Resonance Heating (ICRH) schemes in DT plasma have been considered for the ITER reactor [1]. Most of these heating schemes are minority heating at fundamental frequency. In DT plasma, both reactants can also absorb RF power as majorities at fundamental n=1 or harmonic n=2 frequency. Understanding benefits of directly heatin…
PreprintC.D. Challis J. Hobirk A. Kappatou E. Lerche F. Auriemma E.Belonohy I. Coffey J. Eriksson A. Field M.Fontana J.Garcia A. Ho F. Jaulmes D. Keeling D. King K. Kirov M. Lennholm C.Maggi J.Mailloux M. Maslov S. Menmuir G. Pucella E. Rachlew F. Rimini A. Sahlberg A.Sips E. Solano C. Stuart M. Valisa
A key aim of the 2021 JET deuterium-tritium (D-T) experiments was to demonstrate steady high fusion power (10-15MW) with the ITER-like Be/W first wall. Plasmas were developed using D, repeated with T to investigate and mitigate isotope effects, and run with D-T to maximise fusion power. Compared with high current (q95~3) ‘baseline’ plasmas, …
PreprintV.G. Kiptily Ye.O. Kazakov M. Nocente J. Ongena M. Dreval T. Craciunescu M. Fitzgerald L. Giacomelli V. Goloborodko M.V. Iliasova E.M. Khilkevitch D. Rigamonti A.V. Shevelev J. Garcia J. Oliver S.E. Sharapov Z. Stancar H. Weisen
Alfvén eigenmode (AE) instabilities driven by α-particles have been observed in D-3He fusion experiments on the Joint European Torus (JET) with the ITER-like wall [Kiptily et al, submitted to Phys. Rev. Letters, 2020]. The impact of these type instabilities on a burning plasma is of crucial relevance for the perfor…
PreprintYulin Zhou Benjamin Dudson Fulvio Militello Kiven Verhaegh Omkar Myatra
The role of neutral and charged hydrogenic molecules in detached regimes of tokamak plasmas is investigated using simplified 1D parallel numerical models. Using MAST-Upgrade like conditions, simulations are implemented to study the rollover of target flux in upstream density scan and target temperature scan. It is found that if H2 and H2+ are cons…
PreprintM. Kong E. Nardon M. Hoelzl D. Bonfiglio D. Hu U. Sheikh A. Boboc P. Carvalho T.C. Hender S. Jachmich K.D. Lawson S. Silburn Ž. Štancar R. Sweeney G. Szepesi the JOREK team JET contributors
Shattered pellet injection (SPI), with research started in recent years, is the current concept for the ITER disruption mitigation system (DMS) to prevent disruption-related damage. Compared with impurity SPI, pure deuterium (D2) SPI could contribute to runaway electron (RE) avoidance in ITER via a strong dilution cooling before the thermal quen…
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