B. Din A. I. Blair F. Schoofs D. P. Hampshire
Understanding the properties of grain boundaries in polycrystalline superconductors is essential for optimizing their critical current density. Here, we provide computational simulations of 2D Josephson junctions (JJs) in low magnetic fields using time–dependent Ginzburg–Landau theory, since they can be considered a proxy for a grain boundar…
PreprintL. W. Packer P. Batistoni N. Bekris S. C. Bradnam H. Chohan M. Fabbri Z. Ghani M. R. Gilbert R. Kierepko E. Laszynska D. Leichtle I. Lengarf S. Loreti J. W. Mietelski C. R. Nobs M. Pillon M. I. Savva I. E.Stamatelatos T. Vasilopoulou A. Wojcik-Gargula A. Zoharf JET Contributors
The characteristically intense neutron source generated in deuterium-tritium (DT) fusion power presents notable challenges for materials comprising the structure of the device which are exposed to them. These include radiation damage effects leading to degradation of structural properties with impact on maintenance and replacement frequency, but…
PreprintD. McGarrigle E. Flynn C. Kennedy A. Loving S. Budden
This paper reports on a study of the existing or proposed maintenance arm systems with similar functions and structure to that of the proposed DEMO Multi-Purpose Deployer (MPD).The current MPD design iteration consists of a boom deployment system that is ~30m long and can support a payload of ~1000kg, while still being able to access the DEMO va…
Preprint PublishedD. B. King M. Nicassio A. Ash C. Balshaw A. Barth D. Ciric I. E. Day E. Delabie H. El-Haroun T. T. C. Jones D. Keeling R. King S. Marsden R. McAdams A. McShee S. Merriman A. Shepherd R. Sharma I. Turner T. Wilson
Neutral Beam Injection (NBI) is a very flexible auxiliary heating method for tokamak plasmas, capable of being efficiently coupled to the various plasma configurations required in the Tritium and Deuterium–Tritium Experimental campaign (DTE2) to be undertaken in the JET device. In particular, experiments for high fusion yield and alpha particl…
PreprintEnrique Miralles-Dolz Alexander Pearce James Morris Edoardo Patelli
To make informed decisions during the concept selection activities of a fusion power plant it is necessary to evaluate the impact of uncertainties on the feasibility and performance of each concept. A framework for uncertainty quantification and sensitivity analysis has been developed for the PROCESS systems code to allow the direct comparison o…
PreprintA.J. Pearce S. Kahn J. Morris S.I. Muldrew
Conceptual designs for a European demonstration power plant (EU-DEMO) are based on extrapolations of physics scaling laws and current understanding of engineering limits based on available technologies. It is imperative to quantify the impact of uncertainties in physics and engineering parameters on the ability to produce an economically attract…
PreprintJ. Mitchell A. Parrot F. E. Eriksson F. Casson O. Bardsley M. Lennholm H. Meyer S. Aleiferis
In this paper we present optimized actuator trajectories, evolving in time and space, of non-inductive ramp-up scenarios for the Spherical Tokamak for Energy Production (STEP). These trajectories are computed by solving a non-linear, multi-objective, constrained, finite-time optimal control problem. A method unique to STEP ramp-up studies that prov…
Preprint PublishedS. 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…
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