O. Myatra D. Moulton B. Dudson S. Newton B. Lipschultz K. Verhaegh A. Fil
The role of ion-molecule elastic collisions (specifically D+−D2 collisions) in strongly detached divertor conditions has been studied in the MAST-U Super-X configuration using SOLPS-ITER. Two strongly detached steady state solutions, one obtained through a main-ion (D2) fuelling scan and the other through an impurity (N) seeding scan at fixed fue…
PreprintC. Cowley Bruce Lipschultz David Moulton Ben Dudson
As tokamak research moves to reactor conditions, the control of a stable, optimally-detached divertor plasma has become increasingly relevant. Simple predictions of such detachment control have been performed previously using the Detachment Location Sensitivity (DLS) model of detachment. In this study the DLS model is extended and combined with SOL…
Preprint PublishedT. E. G. Nicholas J. Omotani F. Riva F. Militello B. Dudson
There exists a large body of previous work using reduced two-dimensional models of the SOL, which model fluctuations in the drift-plane but approximate parallel transport with effective loss terms. Full size three-dimensional simulations of SOL turbulence in experimental geometries are now possible, but are far more computationally expensive than …
Preprint PublishedA. Fil B. Lipschultz D. Moulton A. Thornton B. D. Dudson O. Myatra K. Verhaegh the EUROFusion WPTE team
MAST-U has recently started operating with a Super-X divertor, designed to increase total flux expansion and neutral trapping, both predicted through simple analytic models and SOLPS calculations to reduce the plasma and impurity density detachment thresholds. In this study, utilising the SOLPS-ITER code, we are quantifying the possible gain allowe…
Preprint PublishedKevin Verhaegh Basil Duval Ben Dudson Alex Fil Olivier Février Daljeet Gahle James Harrison Omkar Myatra Artur Perek Christian Theiler Mirko Wensing
In this work we provide experimental insights into the impact of plasma-molecule interactions on divertor detachment by applying new spectroscopic analysis techniques to the hydrogen Balmer line series to investigate how both atom and plasma-molecule interactions impact particle balance. Our analysis on a representative L-mode TCV density ramp dis…
Preprint PublishedB. Dudson S. L. Newton J. T. Omotani J. Birch
Drift-reduced MHD models are widely used to study magnetised plasma phenomena, in particular for magnetically confined fusion applications, as well as in solar and astrophysical research. This letter discusses the choice of Ohm’s law in these models, the resulting dispersion relations for the dynamics parallel to the magnetic field, and the i…
Preprint PublishedJ. 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 PurchaseM.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 Published