Showing 1 - 10 of 1596 Journals Results
2020
UKAEA-CCFE-PR(20)117
A. Sperduti M. Cecconello S. Conroy A. Snicker
A discrepancy between predicted and measured neutron rates on MAST using TRANSP/NUBEAM was observed. Further causes of this discrepancy are here studied by means of TRANSP/NUBEAM and ASCOT/BBNBI simulations. Gyro-Orbit simulations resulted in an approximately 20 % reduction of the fast ion density compare to the Guiding Center with TRANSP/NUBEAM an…
Preprint2020
UKAEA-CCFE-PR(20)120
T. Long J.S. Allcock L. Nie R. M. Sharples M. Xu R. Ke S. Zhang S. A. Silburn J. Howard B. Yuan Y. Yu Z.H. Wang X.M. Song L. Liu
A Doppler coherence imaging spectroscopy diagnostic has been developed on the HL- 2A tokamak for scrape-off-layer impurity plasma flow measurements. Two- dimensional imaging of line-averaged C2+ flow in the high-field-…
Preprint2020
UKAEA-CCFE-PR(20)121
Guoliang Xia Yueqiang Liu L. Li C. J. Ham Z . Wang Shuo Wang
Effects of parallel and poloidal flows, as well as the flow shear, on the resistive wall mode (RWM) instability have been numerically investigated in toroidally rotating plasmas, utilizing a recently updated version of the MARS-F code (Liu Y Q et al 2000 Phys. Plasmas 7 3681). A significant difference between these flows i…
Preprint Published2020
UKAEA-CCFE-PR(20)122
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 trans- port model QuaLiKiz. To ensure accurate reproduction of the underlying model, we include known features of the phy…
Preprint Published2020
UKAEA-CCFE-PR(20)123
Vignesh GopakumarD. Samaddar
We propose a method for data-driven modelling of the temporal evolution of the plasma and neutral characteristics at the edge of a Tokamak using neural networks. Our method proposes a novel fully convolutional network that is capable of predicting the time evolution of the physics parameters along the two-dimensional representation of the poloidal …
Preprint2020
UKAEA-CCFE-PR(20)125
Jan Fikara Robin Schaeublin Daniel R. Mason Duc Nguyen-Manh
The vacancies produced in high energy collision cascades of irradiated tungsten can form vacancy clusters or prismatic vacancy dislocation loops. Moreover, vacancy loops can easily transform into planar vacancy clusters. We investigated the formation energies of these three types of vacancy …
Preprint Published2020
UKAEA-CCFE-PR(20)127
S. Saarelma L. Frassinetti P. Bilkova C.D. Challis A. Chankin R. Fridström L. Garzotti L. Horvath C.F. Maggi JET Contributors
The self-consistent core-pedestal prediction model of a combination of EPED1 type pedestal prediction and a simple stiff core transport model is able to predict type I ELMy pedestals of a large database JET-ILW (ITER-like wall) at the similar accuracy as is obtained when the experimental global plasma b is used as input. The neutral penetration mod…
Preprint Published2020
UKAEA-CCFE-PR(20)131
R.A. Tinguely P.G. Puglia N. Fil S. Dowson M. Porkolab A. Dvornova A. Fasoli M. Fitzgerald G.T.A. Huysmans M. Maslov S. Sharapov D. Testa JET Contributors*
This paper presents a dedicated study of plasma-antenna (PA) coupling with the Alfvén Eigenmode Active Diagnostic (AEAD) in JET. Stable AEs and their resonant frequencies f, damping rates < 0, and toroidal mode numbers n are measured for various PA separations and limiter versus X-point magnetic con gurations. Two stable AEs are observed to be …
Preprint2020
UKAEA-CCFE-PR(20)134