Showing 1 - 10 of 1700 Journals Results
2021
UKAEA-CCFE-PR(21)84
Daniel R. Mason Abdallah Reza Fredric Granberg Felix Hofmann
The changing thermal conductivity of an irradiated material is among the principal design considerations for any nuclear reactor, but at present few models are capable of predicting these changes starting from an arbitrary atomistic model. Here we present a simple model for computing the thermal diffusivity of tungsten, based on the conductivity…
Preprint2019
UKAEA-CCFE-PR(19)79
A R Field J M Fontdecaba L Frassinetti L Horvath Hyun-Tae Kim C Maggi C M Roach S Saarelma M Sertoli G Szepeisi JET contributors
The exhaust (loss) power components due to ELMs, radiation and heat transport across the edge transport barrier (ETB) between ELMs are quantifed for H-mode plasmas in JET-C and JET-ILW to provide data for comparison with simulations of pedestal heat transport. In low-current, JET-ILW pulses with a low rate of gas fuelling, the pedestal heat tran…
Preprint Published2021
UKAEA-CCFE-PR(21)83
D.J.M. King A.J. Knowles D. Bowden M.R. Wenman S. Capp M. Gorley J. Shimwell L. Packer M.R. Gilbert A. Harte
This Review considers current Zr alloys and opportunities for advanced zirconium alloys to meet the demands of a structural material in fusion reactors. Zr based materials in the breeder blanket offer the potential to increase the tritium breeding ratio above that of Fe, Si and V based materials. Current commercial Zr alloys might be considered …
Preprint Published2021
UKAEA-CCFE-PR(21)82
J. R. Harrison T. Farley G. M. Fishpool A. Kirk B. Lipschultz J. Lovell F. Militello D. Moulton P. Ryan R. Scannell A. J. Thornton K. Verhaegh L. Xiang
The benefits of an optimised Super-X divertor configuration in mitigating the steady-state power and particle fluxes to the surfaces of the MAST Upgrade divertor have been quantified by performing a detailed comparison with a conventional divertor for the first time. In otherwise identical plasmas with conventional and Super-X divertor configu…
Preprint2021
UKAEA-CCFE-PR(21)81
D. Brunetti C. J. Ham S. Saarelma J. P. Graves J. W. Connor A. Kleiner
The impact of plasma shaping through magnetic well modifications on the stability of resistive ballooning modes in tokamaks is analysed, also including finite diamagnetic flows. Various limiting cases of the dispersion relation, obtained by matching the averaged ballooning equation across the ideal and resistive layers, are analysed. It is found th…
Preprint Purchase2021
UKAEA-RACE-PR(21)06
M. E. Sayed J. O. Roberts K. Donaldson S. T. Mahon F. Iqbal B. Li S. F. Aixela G. Mastorakis E. T. Jonasson M. P. Nemitz S. Bernardini A. A. Stokes
Operations in extreme and hostile environments such as offshore oil and gas, nuclear decommissioning, nuclear facilities maintenance, deep mining, space exploration, and subsea applications require the execution of sophisticated tasks. In nuclear environments, robotic systems have advanced significantly over the past years but still suffer from ta…
Preprint2021
UKAEA-STEP-PR(21)02
J. Fradera S. Sadaba F. Calvo S. Ha S. Merriman P. Gordillo J. Connell A. Elfaraskoury B. Echeveste
As part of the UKAEA Spherical Tokamak for Energy Production (STEP) fusion power station programme, a novel breeding blanket design was assessed. A conceptual design of STEP, which will be an innovative plan for a commercially-viable fusion power station, will be completed by 2024. The final aim of the current assessment is to find a conceptual des…
Preprint2021
UKAEA-RACE-PR(21)05
S. Kirk K. Keogh
The maintenance and decommissioning of nuclear reactors requires the rapid cutting and welding of thick-walled pipework, to which laser processing is highly suited. However, the large size and stand-off of current laser heads precludes their use in space constrained areas and incorporation into in-bore processing tools. To address this, novel minia…
Preprint Published2021
UKAEA-CCFE-PR(21)80
Peng Shi Hongjuan Sun Ge Zhuang Zhifeng Cheng Li Gao Zhipeng Chen Jingchun Li Yinan Zhou the J-TEXT Team
This article reports the first observation of the high-field side high density (HFSHD) in the limiter devices. In the J-TEXT high density discharges, the high-density front at the HFS scrape-off layer (SOL) region edge has been clearly identified by the far-infrared laser polarimeter-interferometer. The HFSHD forms at the HFS SOL, and then expan…
Preprint Purchase2021
UKAEA-CCFE-PR(21)77