Julita Inca Andrew Davis Aleksander Dubas
Preconditioners are meant to improve both, the efficiency and robustness of iterative techniques while solving very large linear systems on a Krylov subspace. However, determining which preconditioner is suitable to be applied on a certain multiphysic simulation requires a combination of knowledge of preconditioning matrices techniques, types of ma…
PreprintFabio Federici Matthew L. Reinke Bruce Lipschultz Andrew J. Thornton James R. Harrison Jack J. Lovell Peter Ryan Matthias Bernert Hendrik F. Meyer the MAST Upgrade team
A prototype infrared video bolometer (IRVB) was succesfully deployed in MAST-U, the first deployment of such a diagnostic in spherical tokamaks. The IRVB was designed to study the radiation around the x-point and has the potential to return emissivity profiles of unprecedented spatial resolution. The system was fully characterised prior installatio…
Preprint PurchaseMark Fedorov Jan S. Wróbel Andrew J. London Krzysztof J. Kurzydłowski Chu-Chun Fu Tonči Tadić Sergei L. Dudarev Duc Nguyen-Manh
Using exchange Monte Carlo (MC) simulations based on an ab initio-parameterized Cluster Expansion (CE) model, we explore the phase stability of low-Cr Fe-Cr alloys as a function of vacancy (Vac), carbon, and nitrogen interstitial impurity content. To parameterise the CE model, we perform density functional theory calculations for more than 1600 …
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…
PreprintAndrew M. Alvarado Hi Vo Tin Jan S. Wr´obel Damian Sobieraj Duc Nguyen-Manh Saryu Jindal Fensin Enrique Martinez Osman El-Atwani
We present a Density Functional Theory-based cluster expansion model to predict the configurational energy of a multicomponent W-Ta-Cr-V-Hf quinary alloy. Coupled with Monte Carlo simulations we show that the model reproduces experimental observations. We analyze the thermodynamic properties of the W.31Ta.34Cr.05V.27Hf.03 system and observe two ph…
PreprintHelen Brooks Stephen Dixon Andrew Davis
We present new two applications, AURORA and Achlys, developed using the MOOSE framework for finite element analysis, intended to facilitate engineering analysis for fusion reactors. Respectively these couple neutronics and tritium transport to native MOOSE physics modules including heat conduction and tensor mechanics. We outline steps taken to pe…
PreprintBin Zhu Nathanael Leung Winfried Kockelmann Saurabh Kabra Andrew J. London Michael Gorley Mark J. Whiting Yiqiang Wang Tan Sui
Eurofer97 steel is a primary structural material for the plasma facing-components of future fusion reactors. Laser welding is a promising technique that can overcome the challenges of remote handling and maintenance. However, the interaction of the induced residual stress distribution with the heterogeneous microstructure may degrade the mechanical…
Preprint PurchaseAndrew R. Warwick Max Boleininger Sergei L. Dudarev
Using atomistic simulations based on the creation-relaxation algorithm, we explore the evolution of microstructure in irradiated zirconium over a broad range of radiation exposure. In agreement with experimental observations, we find that at relatively low temperatures, microstructure evolves towards an asymptotic dynamic steady state forming at…
Preprint PublishedPhillip Gopon James O. Douglas Frederick Meisenkothen Jaspreet Singh Andrew J. London Michael P. Moody
Using a combination of simulated data and pyrite isotopic reference materials, we have refined a methodology to obtain quantitative δ34S measurements from atom probe tomography (APT) datasets. This study builds on previous attempts to characterize relative 34S/32S ratios in gold containing pyrite using APT. We have also improved our understand…
PreprintMarkus Kuhbach Andrew J. London Jing Wang Daniel K. Schreiber FranciscaMendez-Martin Iman Ghamarian Huma Bilal Anna Ceguerra
Atom probe tomography and related methods probe the 3D architecture of a material. Which software tools microscopists use and how these tools are connected into work flows makes a substantial contribution to the accuracy and precision of a materials characterization experiment. Typically, the tools of a specific community adapt results and methods …
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