M. R. Hardman F. I. Parra C. Chong T. Adkins M. S. Anastopoulos-Tzanis M. Barnes D. Dickinson J. F. Parisi H. Wilson
Ion-gyroradius-scale microinstabilities typically have a frequency comparable to the ion transit frequency. Hence, it is conventionally assumed that passing electrons respond adiabatically in ion-gyroradius-scale modes, due to the small electron-to-ion mass ratio and the large electron transit frequency. However, in gyrokinetic simulations of io…
Preprint PublishedT. Adkins A. A. Schekochihin P. G. Ivanov C. M. Roach
Electromagnetic instabilities and turbulence driven by the electron-temperature gradient are considered in a local slab model of a tokamak-like plasma, with constant equilibrium gradients (including magnetic drifts but no magnetic shear). The model describes perturbations at scales both larger and smaller than the electron inertial scale de…
Preprint PublishedA.W. Morris et al
Plenary talk for EPS. First paragraph of abstract: Fusion reactors need to achieve many things simultaneously – this is integration. Embracing it is part of the transition the fusion community is now making, and it brings opportunities as well as challenges: a better solution or more margin in one technical or operation area could enabl…
Preprint PublishedDaniel 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…
Preprint PurchaseA 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 PublishedD.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 PublishedJ. 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…
PreprintC. W. W. Haddon A. I. Blair F. Schoofs D. P. Hampshire
Simulations based on time-dependent Ginzburg–Landau theory are employed to determine the critical current for a model system which represents a Nb–Ti-like pinning landscape at low drawing strain. The system consists of ellipsoids of normal metal, with dimensions 60ξ × 3ξ × 3ξ, randomly distributed throughout the superconducting bulk with t…
Preprint PublishedD. 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 PublishedM. 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…
Preprint Published