UKAEA Journals

Showing 1 - 7 of 7 Journals Results
2019
UKAEA-CCFE-PR(20)120

A Doppler coherence imaging spectroscopy diagnostic has been developed on the HL- 2A tokamak for scrape-off-layer impurity plasma flow measurements. Two- dimensional imaging of line-averaged C2+ flow in the high-field-side scrape off layer with time resolution up to 1 ms, has been achieved successfully by this system. The spatial angular resolut…

Preprint Published
2019
UKAEA-CCFE-PR(19)39

Fusion is one of very few options for sustainable, baseload power to the grid that is necessary to meet the energy needs of future generations. The tokamak is the most advanced approach to fusion and, with the construction of ITER, we are approaching power plant conditions. While commercialisation of this key technology is a main driver for tokamak…

Preprint Published
2014

A new coherence imaging Doppler spectroscopy diagnostic has been deployed on the UK’s Mega Amp Spherical Tokamak for scrape-off-layer and divertor impurity flow measurements. The system has successfully obtained 2D images of C III, C II, and He II line-of-sight flows, in both the lower divertor and main scrape-off-layer. Flow imaging has been obt…

Published
2010

Recently, Bayesian probability theory has been used at a number of experiments to fold uncertainties and interdependencies in the diagnostic data and forward models, together with prior knowledge of the state of the plasma, to increase accuracy of inferred physics variables. A new probabilistic framework, MINERVA, based on Bayesian graphical models…

Published
2008

The theory of variances of equilibrium reconstruction is presented. It complements existing practices with information regarding what kind of plasma characteristics can be reconstructed, how accurately, and what remains beyond the abilities of diagnostic systems. The -curves, introduced by the present theory, give a quantitative assessment of quali…

Published
2004

Simulations of three Joint European Torus [P. H. Rebut et al., Nucl. Fusion 25, 1011 (1985)] type I ELMy high-confinement discharges in a power scan are carried out using the JETTO integrated modeling code [M. Erba et al., Plasma Phys. Controlled Fusion 39, 261 (1997)] with predictive core and pedestal models, which include the effect of edge local…

Published
2004

The time evolution of edge localized modes ( ELMs ) in the Joint European Torus tokamak [ P. H. Rebut and et al. , Nucl. Fusion 25 , 1011 ( 1985 )] is investigated using the JETTO predictive modeling code [ M. Erba and et al. , Plasma Phys. Controlled Fusion 39 , 261 ( 1997 )] . It is found that both pressure-driven ballooning and current-driven pe…

Published