K.L. van de Plassche J. Citrin C. Bourdelle Y. Camenen F. J. Casson V.I. Dagnelie F. Felici A. Ho JET Contributors
We present an ultrafast neural network (NN) turbulent tokamak transport model, QLKNN, for heat and particle fluxes. QLKNN is a surrogate model based on a database of 3 · 108 flux calculations of the quasilinear gyrokinetic transport model QuaLiKiz. To ensure accurate reproduction of the underlying model, we include known features of the…
Preprint PublishedA. Widdowson E. Alves L. Avotina A. Baron Wiechec N. Catarino J P. Coad V. Corregidor K. Heinola I. Jepu JET Contributors
JET has now completed three operating periods, ILW1, ILW2 and ILW3, giving an opportunity to make comparisons between tiles exposed for single operating periods and also comparisons of tiles exposed for all three periods, ILW1-3 (2011-2016). In this contribution, a comprehensive overview of fuel retention and material erosion/deposition patterns…
Preprint PublishedV.G. Kiptily Ye. Kazakov M. Nocente M. Fitzgerald S. Sharapov A.E. Shevelev JET Contributors
Elliptical AE (EAE) and TAE mode instabilities have been observed in hydrogen-rich (nH/(nH+nD)~70-90% JET discharges of so-called “three-ion scenario”, i.e. D-(3He)-H three ion ICRH scenario [1], which is characterized by strong absorption of radio frequency waves a…
Preprint PublishedM Marin J Citrin C Bourdelle Y Camenen F J Casson A Ho F Koechl M Maslov JET Contributors
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 electr…
Preprint PublishedJ. P. Coad M. Rubel J. Likonen N. Bekris S. Brezinsek G. F. Matthews M. Mayer A. M. Widdowson JET contributors
The first divertor was installed in the JET machine between 1992 and 1994 and was operated with carbon tiles and then beryllium tiles in 1994–5. Post-mortem studies after these first experiments demonstrated that most of the impurities deposited in the divertor originate in the main chamber, and that asymmetric deposition patterns generally favou…
PublishedC. Giroud N. Aiba F. Militello C. Challis A. Chankin B. Lomanowski D. Hatch J. Harrison D. Frigione D. Moulton S. Pamela F. Parra J. Parisi I. Putzai D. Refy S. Saarelma C. Stavrou B. Tal E. Belonohy S. Brezinsek S. Buller C. Bowman E. Delabie A. Field J. Fontdecaba A. Huber A. Meigs S. Menmuir J. Simpson JET Contributors
Preprint Published
S.Pamela G.Huijsmans A.J.Thornton A.Kirk S.F.Smith M.Hoelzl T.Eich JET Contributors the MAST Team the JOREK Team
Typically applied to non-linear simulations of MHD instabilities relevant to magnetically confined fusion, the JOREK code was originally developed with a 2D grid composed of isoparametric bi-cubic Bezier finite elements, that are aligned to the magnetic equilibrium of tokamak plasmas. To improve the applicability of these simulations, the grid-gene…
Preprint PublishedCF Maggi H Weisen FJ Casson F Auriemma R Lorenzini H Nordman E Delabie F Eriksson J Flanagan D Keeling D King L Horvath S Menmuir A Salmi G Sips T Tala I Voitsekhovich JET Contributors
NBI-heated L-mode plasmas have been obtained in JET with the Be/W ITER-like wall (JET-ILW) in H and D, with matched profiles of the dimensionless plasma parameters in the plasma core confinement region and same Ti/Te and Zeff. The achieved isotope identity indicates that the confinement scale invariance principle is satisfied in the core confine…
Preprint PublishedM Maslo JET contributors
In 2009-2011 so-called ITER-like wall was installed on JET tokamak, with beryllium limiters and tungsten divertor. Change of the plasma facing materials from carbon to metallic had a significant effect on plasma operations and confinement. Achieving steady plasma performance has become more challenging due to impurity accumulation [1], which has pu…
Preprint PublishedCF Maggi H Weisen L Horvath F Auriemma R Lorenzini E. Delabie D King D Keeling S Menmuir JET Contributors
Dimensionless identity experiments test the invariance of plasma physics to changes in the dimensional plasma parameters, e.g. ne and Te, when the dimensionless parameters are conserved [1] [2]. However, conditions at the plasma boundary, such as influx of neutral particles, may introduce additional physics. An isotope identit…
Preprint Published