S. Omole A. J. G. Lunt S. Kirk A. Shokrania
The high ductile-to-brittle transition temperature (DBTT) of tungsten combined with its high hardness make machining incredibly difficult. These properties typically result in the poor-quality machined surfaces and short tool life. In this study, TiAlN coated carbide tools with different rake angles (8°, 10° and 12°) were tested in convention…
PreprintHelen Brooks Andrew Davis
To support the design of fusion reactors for energy production, there is an urgent need to develop highly-scalable multi-physics software tools capable of modelling critical tokamak components as a single cohesive whole. Although some loosely-coupled physics tools do exist, these lack fidelity and will fundamentally fail to capture any closed-lo…
Preprint PublishedM.Yu. Lavrentiev A. Hollingsworth J. Hess S. Davies A. Wohlers B. Thomas H.Salter A. Baron-Wiechec I. Jepu Y. Zayachuk N. Peng
Molybdenum is used as plasma-facing material in tokamaks and as material for plasma optical diagnostic mirrors. Harsh conditions of neutron irradiation, exposure to hydrogen isotopes and helium, and high temperature result in degradation of molybdenum surface and ultimately limit the lifetime of fusion power plant. In the current paper, we inves…
PreprintJ. R. Echols L. M. Garrison N. Reid C. M. Parish D. Morrall A. Hasegawa A. Bhattacharya Y. Katoh
A major challenge for heat transfer in nuclear materials is to ensure thermal mobility after high amounts of neutron irradiation. Tungsten is widely selected as a heat transfer material in fusion reactors. In metals, thermal conductivity is dominated by electrons’ ability to transfer energy. Neutron irradiation generates point defects, c…
Preprint PublishedK. G. McClements M. Fitzgerald H. J. C. Oliver A. P. Prokopyszyn
The UK has launched a programme to build a prototype fusion power plant, the Spherical Tokamak for Energy Production (STEP), by 2040. It is intended that the STEP prototype will generate fusion power of the order of 1 GW and net electrical power of the order of 100 MW. Plasma scenarios that could be compatible with these design requirements and wit…
PreprintT. Wilson S.J. Freethy M. Henderson A Köhn-Seeman I. Konoplev S. Saarelma D. Speirs R.G.L. Vann the STEP team
The UK’s Spherical Tokamak for Energy Production (STEP) reactor design program is now exclusively investigating concepts using microwave-based heating and current drive (HCD) systems. Electron Bernstein Wave (EBW) HCD is a relatively immature technology compared to Electron Cyclotron (EC) HCD but is of interest due to the promise of high current…
PreprintM. Kong E. Nardon M. Hoelzl D. Bonfiglio D. Hu U. Sheikh A. Boboc P. Carvalho T.C. Hender S. Jachmich K.D. Lawson S. Silburn Ž. Štancar R. Sweeney G. Szepesi the JOREK team JET contributors
Shattered pellet injection (SPI), with research started in recent years, is the current concept for the ITER disruption mitigation system (DMS) to prevent disruption-related damage. Compared with impurity SPI, pure deuterium (D2) SPI could contribute to runaway electron (RE) avoidance in ITER via a strong dilution cooling before the thermal quen…
PreprintGuoliang Xia T.C. Hender Yueqiang Liu E. Trier
The Spherical Tokamak for Energy Production (STEP) is a UKAEA program that aims to deliver a prototype fusion energy plant and a path to commercial viability of fusion [1]. The low aspect ratio spherical tokamak is attractive because of its potential to achieve high normalized beta βN operation, and the fusion power ~β…
PreprintJoshua Blake Guy Burroughes Kaiqiang Zhang
This paper describes a novel automatic solution for toolchanging operations using dexterous teleoperated robots in a nuclear glovebox. This solution can identify and locate tools in the nuclear glovebox by visually tracking augmented reality (AR) tags online at a low computational cost. The solution is designed in a modular manner taking into ac…
PurchaseL. Kogan D. Ryan S. Gibson J. Berkery S. Sabbagh T. Farley P. Ryan K. Verhaugh B. Kool T.A. Wijkamp R. Scannell R. Sarwar C. Wade the MAST-U team
The MAST-U spherical tokamak has extensive capabilities to produce and explore strongly shaped plasmas and alternative divertor configurations, especially the Super-X. Robust and accurate reconstructions of plasma equilibria are the foundation of many physics analyses, as well as being important intershot for informing operation of the tokamak. …
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