F. Dhalla S. Mistry I. Turner T.R. Barrett I. Day R. McAdams
For the initial phase of MAST-U operation the two existing neutral beam injection systems will be used, but must be substantially upgraded to fulfil expected operational requirements. The major elements are the design, manufacture and installation of a bespoke bending magnet and Residual Ion Dump (RID) system. The MAST-design full energy dump is b…
Preprint PublishedI.E. Day T.T.C. Jones JET EFDA Contributors
We describe the operational experience of the JET actively cooled duct liner and compare it with the previous inertially cooled duct. The paper discusses the initial conditioning of the duct liner during restart commissioning and subsequent high power performance. The new duct was conditioned in 48 plasma pulses during its first time commissioning …
Preprint PublishedA.D. Ash T.T.C. Jones E. Surrey D. Ciric S.I. Hall D. Young M. Afzal L. Hackett I.E. Day R. King JET EFDA Contributors
The JET Neutral Beam Injection (NBI) system is the most powerful neutral beam plasma heating system currently operating. Optical Interlocks were installed on the beam lines in 2011 for the JET Enhancement Project 2 (EP2), when the heating power was increased from 23 MW to 34 MW. JET NBI has two beam lines. Each has eight positive ion injectors oper…
Preprint PublishedM.J.Gorley
The development of new, high-performance reduced activation materials is increasingly recognised as one of the key enabling technologies required for the advancement of civil fusion power. To comply with the fusion ethos of no material entering the permanent active waste disposal route, reduced activation steels have been developed and are consider…
Preprint PublishedD. L. Keeling T. R. Barrett M. Cecconello C. D. Challis N. Hawkes O. M. Jones I. Klimek K. G. McClements A. Meakins J. Milnes M. Turnyanskiy The MAST team
The phenomenon of redistribution of neutral beam fast-ions due to MHD activity in plasma has been observed on many tokamaks and more recently has been a focus of research on MAST ( Turnyanskiy M. et al, 2013 Nucl. Fusion 53 053016 ). n=1 fishbone modes are observed to cause a large decrease in the neutron emission rate indicating to exist a signifi…
Preprint PublishedA.J. Thornton G. Fishpool A. Kirk The MAST Team The EUROfusion MST1 Team
Filamentary transport across the scrape off layer is a key issue for the design and operation of future devices, such as ITER, DEMO and MAST-U, as it sets the power loadings to the divertor and first wall of the machine. Analysis has been performed on L mode filaments in MAST in order to gain an understanding of the spatial structure and attempt to…
Preprint PublishedE. Havlíčková J. Harrison B. Lipschultz G. Fishpool A. Kirk A. Thornton M. Wischmeier S. Elmore S. Allan
SOLPS simulations of MAST-U have been carried out to identify in more detail the physics and operational properties of novel divertor configurations such as Super-X divertor (SXD), in particular the physics of detachment. A well diagnosed L-mode discharge from MAST has been utilised to determine L-mode transport coefficients representative for MAST…
Preprint PublishedH. T. Kim M. Romanelli I. Voitsekhovitch T. Koskela J. Conboy C. Giroud G. Maddison E. Joffrin JET contributors
A consistent deterioration of global confinement in H-mode experiments has been observed in JET [1] following the replacement of all carbon Plasma Facing Components (PFCs) with an all metal (‘ITER-like’) wall (ILW). This has been correlated to the observed degradation of the pedestal confinement, as lower electron temperature (T e ) values are …
Preprint PublishedE. Surrey A.J.T. Holmes
A one dimensional model of the magnetic multipole volume plasma source has been developed for application to intense ion/neutral atom beam injectors. The model uses plasma transport coefficients for particle and energy flow to create a detailed description of the plasma parameters along an axis parallel to that of the extracted beam. In this paper …
Preprint PublishedM. Romanelli V. Parail P. da Silva Aresta Belo G. Corrigan L. Garzotti D. Harting F. Koechl E. Militello-Asp R. Ambrosino M. Cavinato A. Kukushkin A. Loarte M. Mattei R. Sartori
ITER operations require effective fuelling of the core plasma for conditions in which neutral dynamics through the scrape-off layer (SOL) is expected to affect significantly the efficiency of gas penetration. On the basis of previous analysis for stationary conditions, pellets are foreseen to provide core fuelling of high-Q DT scenarios. In this pa…
Preprint Published