UKAEA Journals

Showing 1 - 10 of 1684 Journals Results
2021
UKAEA-CCFE-PR(21)63

The 2D scrape-off-layer turbulence code (nSOLT) includes 1D Boltzmann neutral-plasma interactions, a model of divertor recycling (introduced here), and a fixed source of plasma concentrated at the core-side boundary. 1) Neutral injection in the far-SOL is accomplished by specifying the density of Franck-Condon distributed neutrals streaming in from…

Preprint Published
2020
UKAEA-CCFE-PR(21)63

The optimum conditions for access to and sustainment of H-mode plasmas and their expected plasma parameters in the Pre-Fusion Power Operation 1 (PFPO-1) phase of the ITER Research Plan, where the additional plasma heating will be provided by 20 MW of Electron Cyclotron Heating (ECH), are assessed in order to identify key open R&D issues. The as…

Preprint
2021
UKAEA-CCFE-PR(21)62

Drift-reduced MHD models are widely used to study magnetised plasma phenomena, in particular for magnetically con ned 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 impli…

Preprint
2020
UKAEA-CCFE-PR(21)62

Reconstructions of plasma equilibria using magnetic sensors and a Dα constraint were routine during operation of the MAST spherical tokamak, but reconstructions using kinetic profiles was not. These are necessary for stability and disruption analysis of the MAST database, as well as going forward for operation in the upgrade to the device, MAST-U.…

Preprint
2020
UKAEA-CCFE-PR(21)62

The optimum conditions for access and sustainment of H-mode plasmas and their expected plasma parameters in the Pre-Fusion Operation 1 (PFPO-1) phase of the ITER Research Plan, where the additional plasma heating will be provided by 20 MW of Electron Cyclotron Heating (ECH), are assessed. The assessment is performed on the basis of empirical and ph…

Preprint Purchase
2020
UKAEA-CCFE-PR(21)62

Alfvén eigenmode (AE) instabilities driven by alpha-particles have been observed in D-3He fusion experiments on the Joint European Torus (JET) with the ITER-like wall (ILW). For the efficient generation of fusion alpha-particles from D-3He fusion reaction, the 3‑ion radio frequency (RF) scenario was used t…

Preprint Published
2019
UKAEA-CCFE-PR(21)62

We present the rst parallel electron transport results obtained using the newly developed 1D transport code SOL-KiT. In order to properly predict divertor heat loads it is of key importance to develop a thorough understanding of discrepancies between diff erent parallel transport modelling approaches. With the capability to self-consistently s…

Preprint Published
2021
UKAEA-CCFE-PR(21)61

We use beam tracing — implemented with a newly-written code, Scotty — and the reciprocity theorem to derive a model for the linear backscattered power of the Doppler Backscattering (DBS) diagnostic. Our model works for both the O-mode and X-mode in tokamak geometry (and certain regimes of stellarators). We present the analytical derivation of o…

Preprint
2021
UKAEA-CCFE-PR(21)60

Using atomistic simulations based on the creation-relaxation algorithm, we explore the evolution of microstructure in irradiated zirconium over a broad range of radiation exposure. In agreement with experimental observations, we find that at relatively low temperatures, microstructure evolves towards an asymptotic dynamic steady state forming at…

Preprint
2021
UKAEA-CCFE-PR(21)58

This paper presents recent progress on the studies of neoclassical tearing modes (NTMs) on TCV, concerning the new physics learned and how this physics contributes to a better real-time (RT) control of NTMs. A simple technique that adds a small (sinusoidal) sweeping to the target electron cyclotron (EC) beam deposition location has proven effective…

Preprint