UKAEA Journals

Showing 1 - 10 of 400 Journals Results
2021
UKAEA-CCFE-PR(21)39

A recently updated version of the MARS-F code [Y. Q. Liu et al. Phys. Plasmas 7, 3681 (2000); L. Li et al. Phys. Plasmas 25, 082512 (2018); G. L. Xia et al. Nucl. Fusion 59, 126035 (2019)] is utilized to numerically investigate the plasma screening effect on the applied resonant magnetic perturbation (RMP) field, assuming various equilibrium flo…

Preprint
2021
UKAEA-CCFE-PR(21)38

Ion cyclotron resonance heating (ICRH) is one of the three additional heating schemes to be deployed on ITER. Its two antenna arrays, installed on the outboard midplane, will deliver 20 MW of RF power in the 40-55 MHz frequency range. The plasma-facing component of …

Preprint Purchase
The published version of this paper is currently under embargo and will be available on 18/05/2023
2021
UKAEA-CCFE-PR(21)35

Sustained operation of high-performance, ITER-baseline scenario plasmas at the high levels of input power (~< 40MA) required to achieve ~ 15 MW of D-T fusion power in JET-ILW requires careful optimisation of the fuelling to avoid an unacceptable disruption rate due to excessive radiation, primarily from W impurities, which are sputter…

Preprint
2021
UKAEA-CCFE-PR(21)32

For the first time, a digital Mirror Langmuir probe (MLP) has successfully sampled plasma temperature, ion saturation current, and floating potential together on a single probe tip in real time in a radio-frequency driven helicon linear plasma device. This is accomplished by feedback control of the bias sweep to ensure a good fit to I-V charact…

Preprint
2021
UKAEA-CCFE-PR(21)19

A novel high-performance computing algorithm, developed in response to the next generation of computational challenges associated with burning plasma regimes in ITER-scale tokamak devices, has been tested and is described herein. LOCUST-GPU 2 The Lorentz-Orbit Code for Use in Stellarators and Tokamaks (LOCUST) is designed for computationally s…

Preprint
2021
UKAEA-CCFE-PR(21)08

A survey of the correlation between temperature and density gradient lengths ( and ) has been performed for the near SOL regions in the ASDEX Upgrade tokamak. In common with previous studies, the near SOL temperature and density gradient length ratio, , is found to be close to unity across a wide range of plasmas. However, it is found that it is po…

Preprint Published
2021
UKAEA-CCFE-PR(21)02

In quiescent H-mode (QH-mode) regime, edge harmonic oscillations (EHOs) are believed to provide necessary radial transport to prevent occurrence of large edge localized modes. A systematic modeling study is performed here on the low-n EHOs in a DIII-D QH-mode plasma [Chen et al. 2016 Nucl. Fusion 56 076011], by utilizing the MARS-Q code [Liu et a…

Preprint Purchase
The published version of this paper is currently under embargo and will be available on 22/03/2022
2020
UKAEA-CCFE-PR(20)141

Using ab initio density function theory calculations, we have determined the structure of self-interstitial atom (SIA) defects in the most commonly occurring face-centred cubic (FCC) metals. The most stable SIA defects in Al, Ca, Ni, Cu, Pd and Ag are the {100} dumbbells whereas octahedral SIA configurations have the lowest energy in Pt, R…

Preprint Published
2020
UKAEA-CCFE-PR(20)138

The electron runaway phenomenon in plasmas depends sensitively on the momentum space dynamics. However, efficient simulation of the global evolution of systems involving runaway electrons typically requires a reduced fluid description. This is needed for example in the design of essential runaway mitigation methods for tokamaks. In this paper, we p…

Preprint Purchase
2020
UKAEA-CCFE-PR(20)132

Mechanical constitutive models of metals undergoing deformation in three dimensions can be challenging to validate without loss of generality. For example, creep-induced stress relaxation in stainless steels has previously been studied using axisymmetric notched-bar tests which control the triaxiality of the initial stress state. However, such expe…

Preprint