J. T. Parker P. A. Hill D. Dickinson B. D. Dudson
Tridiagonal matrix inversion is an important operation with many applications. It arises frequently in solving discretized one-dimensional elliptic partial differential equations, and forms the basis for many algorithms for block tridiagonal matrix inversion for discretized PDEs in higher-dimensions. In such systems, this operation is often the …
Preprint PublishedM.S. Anastopoulos-Tzanis B.D. Dudson C.J. Ham C.C. Hegna P.B. Snyder H.R. Wilson
A linear perturbation theory is used to model the MHD stability of tokamak equilibria under the application of external 3D magnetic perturbations [C.C. Hegna, Physics of Plasmas 21 :072502, 2014]. The symmetry breaking produces the coupling of toroidal n modes. We use ELITE [H.R. Wilson et al., Physics of Plasmas 9 :1277, 2002] to produ…
Preprint PublishedA. Fil B. Dudson B. Lipschultz D. Moulton O. Myatra K. Verhaegh O. Fevrier J. Harrison A. Thornton M. Wensing
Plasma detachment needs to be achieved in ITER [1] and future devices such as DEMO to dissipate most of the power in the Scrape-Off-Layer (SOL) and reduce the particle flux reaching the divertor targets. In order to enhance our capability to improve current, and design future tokamaks, we must improve our understanding of the relative effect on det…
Preprint PublishedF. Militello R. Akers L. Appel B. Cannas S. Carcangiu B. Dudson A. Fanni T. Farley A. Kirk J.R. Harrison B. Lipshultz A. Montisci T. Nicholas J.T. Omotani F. Pisano F. Riva G. Sias N.R. Walkden A. Wynn the MAST JET5 teams
In magnetic confinement devices, boundary turbulence is responsible for transporting plasma and energy from the well-confined region towards the material surfaces where it can severely harm reactor relevant machines. It is therefore essential to develop a solid understanding of the mechanisms behind the transport in the edge of the plasma. Large fl…
Preprint PublishedF. Riva F. Militello J. T. Omotani B. Dudson S. D. Elmore S. Newton T. Nicholas N. R. Walkden the MAST team
In the present work, global, three-dimensional edge plasma turbulence simulations of a MAST L-mode attached plasma discharge are presented. Our study is based on the drift-reduced Braginskii equations, solved with the STORM module of BOUT++ for realistic MAST parameters in disconnected lower double null configuration. The plasma profiles are evolve…
Preprint PublishedDavid Schworer Nick Walkden Ben Dudson Fulvio Militello Huw Leggate Miles Turner
The here presented work studies the dynamics of filaments using 3D full-f fluid simulations in the presence of detached background profiles. It was found that evolving the neutrals on the time-scale of the filament did not have a significant impact on the dynamics of the filament. In general a decreasing filament velocity with increasing plasma den…
Preprint PublishedN.R.Walkden B.D.Dudson C.Ham F.Militello D.Moulton F.Riva J.T.Omotani
A firm grasp of transport processes perpendicular to the magnetic field line is required in order to understand and predict heat and particle fluxes to divertor components in tokamaks. Perpendicular transport from the hot core into the scrape-off layer (SOL) upstream impacts the SOL profile at the divertor via parallel streaming along the magnetic …
Preprint PurchaseD A Ryan L Piron A Kirk Y Q Liu M Dunne L Li B Dudson W Suttrop the ASDEX Upgrade team the EUROfusion MST1 team
Edge Localised Modes (ELMs) in H-mode tokamak plasmas may be controlled or entirely suppressed by applying 3D magnetic perturbations (MPs). The applied perturbation is amplified by the plasma response, and it has previously been established that the size of the peeling component of this response is a reliable indicator for expected ELM control on A…
PreprintA. Fil D. Moulton B. Dudson B. Lipschultz K. Verhaegh O. Février O. Myatra C. Theiler M. Wensing EUROfusion MST1 teams the TCV team
In ITER and DEMO, achieving detachment at lower densities would allow to reduce the amount of impurity seeded and to improve confinement by running at lower separatrix densities. Analytic models predict that a increase of total flux expansion would allow such a reduction in upstream density at detachment. However, both experiments and modelling …
Preprint PublishedF. Riva F. Militello S. Elmore J. T. Omotani B. Dudson N. R. Walkden MAST team
The STORM module of BOUT++ [L. Easy et al., Phys. Plasmas 21, 122515 (2014)] is generalized to simulate plasma turbulence at the periphery of tokamak devices in diverted configuration and it is used to carry out three-dimensional nonlinear flux-driven simulations in double null configuration with realistic experimental par…
Preprint Published