Pui-Wai Ma D. R. Mason S. L. Dudarev
We performed ab initio density functional theory simulations of 1/2{111} interstitial dislocation loops, closed and open vacancy loops, {100} interstitial loops and voids in tungsten, using simulation cells involving from 2000 to 2700 atoms. The size of the loops transcends the microscopic scale and reaches the mesoscopic scale where as…
Preprint PublishedCameron McElfresh Yinan Cui Sergei Dudarev Giacomo Po Jaime Marian
Dislocation climb is an important high temperature process of metals plasticity, responsible for phenomena such as creep, swelling, or hardening. Climb is defined by the ability of dislocations to leave their original glide plane by interaction with point defects. As such, dislocation climb is controlled by point defect diffusion/absorption/emis…
Preprint PublishedArtem Lunev Vadim Zborovskii Teymur Aliev
Thermal diffusivity measurements of samples transmitting thermal radiation require adjustments to the data treatment procedures in laser flash analysis. Conventionally, an unconstrained diathermic model is used. Current results show that the alternative coupled radiative-conductive models produce substantially different results — for instance,…
Preprint PublishedFederico Baraglia Pui-Wai Ma
We develop a dynamic model for the evolution of an ensemble of hundreds of interacting irradiation-induced mobile nanoscale defects in a micrometre size sample. The model uses a Langevin defect dynamics approach coupled to a finite element model, treated using the superposition method. The elastic field of each defect is described by its elastic…
Preprint PublishedYuling He Yueqiang Liu Xu Yang Guoliang Xia Li Li
Modification of the external tearing index, Δ’ext , by magnetic feedback is analytically investigated, for the purpose of controlling the resistive plasma resistive wall mode (RP-RWM). The matching method is pursued, by deriving expressions for the close-loop Δ’ext and by linking it to the counterpart from the inner layer. Various…
Preprint PublishedM J Dunn T W Morgan J W Genuit T Loewenhoff A J Thornton K J Gibson the Magnum-PSI team
One of the issues faced by future fusion devices will be high target heat loads. Alternative divertors are a potential solution to the heat loads. They have been investigated in TCV and DIII-D, and will be investigated on MAST-U. To evaluate their effectiveness, accurate target heat flux and power balance measurements are required in these machines…
Preprint PublishedM. Sasaki T. Kobayashi R. O. Dendy Y. Kawachi H. Arakawa S. Inagaki
A method to quantify the energy transfer among turbulent structures using singular value decomposition (SVD) is presented. We apply the method to numerical turbulence data obtained from a global plasma simulation using the Hasegawa-Wakatani fluid model, in which the Kelvin-Helmholtz instability plays a dominant role. Using the SVD method,…
Preprint PublishedD. Moulton P. C. Stangeby X. Bonnin R. A. Pitts
If correct, the Lengyel model offers a simple and powerful tool to predict the conditions required for detachment onset in future fusion reactors. We assess its validity against a comprehensive SOLPS-4.3 simulation database of ITER baseline (Q = 10) neon-seeded plasmas (Pacher et al 2015 J. Nucl. Mater. 463 591). In absolute terms, the Lengyel Mode…
Preprint PublishedV.G. Kiptily M. Fitzgerald Ye.O. Kazakov M. Nocente J. Ongena S.E. Sharapov M. Dreval Ž. Štancar T. Craciunescu J. Garcia L. Giacomelli V.Goloborodko J. Oliver H. Weisen
Dedicated experiments to generate high-energy D ions and D-3He fusion-born alpha particles have been performed at the Joint European Torus (JET) with the ITER-like wall (ILW). Deuterium ions from neutral beam injection (NBI) with acceleration voltage of 100 keV were accelerated to higher energies in the core of mixed D-3He…
Preprint PublishedF. Domptail T.R. Barrett M. Fursdon A. Lukenskas J-H. You
A high performing DEMO divertor target mock-up design that uses the thermal break interlayer concept is presented. The design evolved from a previous design of which six mock-ups were designed, fabricated and subjected to high heat flux testing. The new design was generated using optimisation techniques; specifically, software was developed to …
Preprint Published