F. 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 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 PurchaseF. 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 PublishedF. Militello T. Farley K. Mukhi N. Walkden J.T. Omotani
A statistical framework was introduced in textit{Militello et al., Nucl. Fusion 56, 104004 (2016)} to correlate the dynamics and statistics of L-mode and inter-ELM plasma filaments with the radial profiles of thermodynamic quantities they generate in the Scrape Off Layer. This paper extends the framework to cases in which the filaments are emitted …
Preprint PublishedP.M.S. Buller I. Pusztai S.L. Newton J.T. Omotani
In tokamak transport barriers, the radial scale of profile variations can be comparable to a typical ion orbit width, which makes the coupling of the distribution function across flux surfaces important in the collisional dynamics. We use the radially global steady-state neoclassical f code Perfect to calculate poloidal and toroidal flows, and radi…
Preprint PublishedJ. Omotani I. Pusztai S. Newton T. Fülöp
Neutral atoms can strongly influence the intrinsic rotation and radial electric field at the tokamak edge. Here, we present a framework to investigate these effects when the neutrals dominate the momentum transport. We explore the parameter space numerically, using highly flexible model geometries and a state of the art kinetic solver. We find that…
Preprint PublishedF. Militello J.T. Omotani
A theoretical framework is developed to clarify the relation between the profiles of density and temperature in the Scrape Off Layer (SOL) with the fluctuations (filaments) that generate them. The framework is based on the dynamics of independent filaments and on their statistical behaviour and can be used to rigorously understand the mechanisms th…
Preprint PublishedN. R. Walkden L. Easy F. Militello J. T. Omotani
Simulations have been carried out to establish how electron thermal physics, introduced in the form of a dynamic electron temperature, affects isolated filament motion and dynamics in 3D. It is found that thermal effects impact filament motion in two major ways when the filament has a significant temperature perturbation compared to its density per…
Preprint PublishedJ.T. Omotani F. Militello L. Easy N.R. Walkden
A complete model of the dynamics of scrape-off layer filaments will be rather complex, including temperature evolution, three dimensional geometry and finite Larmor radius effects. However, the basic mechanism of E x B advection due to electrostatic potential driven by the diamagnetic current can be captured in a much simpler model; a complete unde…
Preprint Published