UKAEA Journals

Showing 1 - 9 of 9 Journals Results
2019
UKAEA-CCFE-PR(19)75

The evolution of the JET high performance hybrid scenario, including central accumulation of the tungsten (W) impurity, is reproduced with predictive multi-channel integrated modelling over multiple confinement times using first-principle based models. 8 transport channels are modelled predictively, with self-consistent sources, radiation and magne…

Preprint Purchase
2019
UKAEA-CCFE-PR(19)52

This work describes the behaviour of the global energy and particle confinement on JET observed in a massive database of H-mode plasmas covering almost whole lifetime of JET operations, both with carbon and metal wall. The analysis is focused on type I ELMy H-modes in stationary phases. It is shown that plasma density in that regime is determined m…

Preprint Published
2016
CCFE-PR(16)81

Recent improvements in software tools and methodology have allowed us to perform a more comprehensive in-vessel calibration for all mid-infrared camera systems at JET. A comparison of experimental methods to calculate the non-uniformity correction is described as well as the linearity for the different camera systems. Measurements of the temperatur…

Preprint Published
2015
CCFE-PR(15)13

A large number of materials exist which have been labeled as low activation structural materials (LAM). Most often, these materials have been designed in order to substitute-out or completely remove elements that become activated and contribute signi cantly to shut-down activity after being irradiated by neutrons in a reactor environment. To date, …

Preprint Published
2010

Pellet material deposited in a tokamak plasma experiences a drift towards the low field side of the torus induced by the magnetic field gradient. Plasma fuelling in ITER relies on the beneficial effect of this drift to increase the pellet deposition depth and fuelling efficiency. It is therefore important to analyse this phenomenon in present machi…

Published
2005

Recently, it was shown that intermittency observed in magnetic fusion devices is caused by large-scales events with high radial velocity reaching about 1/10th of the sound speed s called avaloids or blobs [G. Antar and et al. , Phys. Rev. Lett. 87 065001 (2001)]. In the present paper, the poloidal distribution of turbulence is investigated on the M…

Published
2004

The Mega Amp Spherical Torus ( MAST ) diagnostic needs are strongly influenced by physics goals that often require diagnostic integration and cross-mapping, especially in fine-scale investigations, such as transport barriers. Conversely, the unrivalled viewing access to the edge, scrape-off layer ( SOL ) and divertor regions, provided by the MAST o…

Published
2004

This Letter provides information on the spatial and temporal structure of periodic eruptions observed in magnetically confined laboratory fusion plasmas, called edge-localized modes (ELMs), and highlights similarities with solar eruptions. Taken together, the observations presented in this Letter provide strong evidence for ELMs being associated wi…

Published
1999

Theoretical modeling of 1–2 MW positive hydrogen ion neutral injectors developed at Oak Ridge National Laboratory ~ORNL! has suggested that the plasma grid temperature could rise by up to 180 °C at pulse lengths above 0.5 s, leading to a grid deformation on the order of 5 mm, with a consequent change in focal length (from 4 to 2 m) and beamlet f…

Published