Llion Marc Evans

Llion Marc Evans
Swansea University | SWAN · Zienkiewicz Centre for Computational Engineering

BSc 1st (Hons), MSc, PhD

About

29
Publications
13,073
Reads
How we measure 'reads'
A 'read' is counted each time someone views a publication summary (such as the title, abstract, and list of authors), clicks on a figure, or views or downloads the full-text. Learn more
174
Citations
Introduction
Dr Llion Marc Evans holds an EPSRC Manufacturing Research Fellowship (2018-2023) at the College of Engineering, Swansea University. His main research interest is industrial application of the image-based finite element method (IBFEM) in high-value manufacturing (HVM) for Virtual Qualification. Dr Evans completed his PhD at the School of Materials, University of Manchester (2013) as part of the ‘Fusion Doctoral Training Network’. Since 2009 Dr Evans has worked on IBFEM, a process which converts 3D data (e.g. X-ray tomography) into high-res simulations thus capturing features such as manufacturing defects. 2013-2018 he worked at UKAEA applying IBFEM to investigate the manufacturing process for high heat flux components being designed for DEMO, the first demonstrational fusion power plant.
Additional affiliations
February 2018 - present
Swansea University
Position
  • Fellow
September 2017 - present
The University of Manchester
Position
  • Academic Supervisor
Description
  • Academic supervisor of PhD student investigating "Advanced virtual design of 3D printed fusion reactor components"
June 2016 - June 2016
Science and Technology Facilities Council
Position
  • Course co-organiser
Description
  • Hartree Centre Summer School, Engineering Simulation
Education
April 2010 - December 2013
The University of Manchester
Field of study
  • Materials Science
September 2009 - March 2010
The University of York
Field of study
  • Fusion Doctoral Training Network
September 2006 - September 2007
Imperial College London
Field of study
  • Advanced Computational Methods for Aeronautics, Flow Management & Fluid Structure Interaction

Publications

Publications (29)
Poster
Full-text available
WebCT is a browser-based tool to run interactive X-ray simulations and tomographic reconstructions with a focus on rapid and accurate results. Leveraging existing open-source technologies such as gVirtualXRay for GPU-based X-ray simulations, alongside spekpy and xpecgen for spectra generation with CCPi's CIL library for tomographic reconstruction,...
Article
Full-text available
The divertor target plates are the most exposed in-vessel components to high heat flux loads in a fusion reactor due to a combination of plasma bombardment, radiation and nuclear heating. Reliable exhaust systems of such a huge thermal power required a robust and durable divertor target with a sufficiently large heat removal capability and lifetime...
Article
Full-text available
In this work, the potential of carrying out inverse problems with linear and non-linear behaviour is investigated using deep learning methods. In inverse problems, the boundary conditions are determined using sparse measurement of a variable such as velocity or temperature. Although this is mathematically tractable for simple problems, it can be ex...
Conference Paper
Full-text available
Material nonlinearity is implemented in finite element programs using mathematical models of material behaviour. These are typically defined by a set of parameters whose values are determined from experimental data. These constitutive models are phenomenological; that is they describe nonlinear material behaviour, but do not explicitly model the ph...
Article
Functional materials' properties are influenced by microstructures which can be changed during manufacturing. A technique is presented which digitises graphite foam via X-ray tomography and converts it into image-based models to determine properties in silico. By simulating a laser flash analysis its effective thermal conductivity is predicted. Res...
Article
Full-text available
Neutron Tomography (NT) is a non-destructive technique to investigate the inner structure of a wide range of objects and, in some cases, provides valuable results in comparison to the more common X-ray imaging techniques. However, NT is time consuming and scanning a set of similar objects during a beamtime leads to data redundancy and long acquisit...
Conference Paper
Full-text available
This paper presents the application of the image-based finite element method (IBFEM) to quantify the impact of micro-structure caused by manufacturing processes on the performance of fusion energy heat exchangers. The components, containing tungsten, were imaged with high-power lab-based X-ray CT and neutron CT. Volume data was converted into part-...
Article
Virtual engineering is being widely adopted in diverse technical fields and has the potential to accelerate the realization of tokamak fusion energy. In this paper, we demonstrate, for the first time, the use of virtual engineering techniques to enhance the development cycle of a water-cooled divertor plasma facing component. The divertor concept u...
Article
Within a tokamak fusion energy device, the performance and lifespan of a divertor monoblock under high heat flux cycles is of particular interest. Key to this is the quality of manufacture, especially the material joining interfaces. Presented here is a comparative study between X-ray and neutron tomography to investigate the quality of manufacture...
Article
Full-text available
The design and development of a novel plasma facing component (for fusion power plants) is described. The component uses the existing 'monoblock' construction which consists of a tungsten 'block' joined via a copper interlayer to a through CuCrZr cooling pipe. In the new concept the interlayer stiffness and conductivity properties are tuned so that...
Conference Paper
Full-text available
Plasma exhaust and protection of the plasma-facing components are critical aspects of DEMO-class devices, so there needs to be high confidence in solutions for the plasma and the materials and components. A special feature of fusion is the choice to take large steps (JET to ITER to DEMO in the EU) to control the time and cost of the development of...
Presentation
Full-text available
Presented as an invited talk at the Fusion Workshop at IYNC2016, this presentation gave an introductory overview on the current status and future roadmap for global fusion energy research with particular emphasis from the European perspective.
Poster
Full-text available
Components designed to be used within the nuclear sector (both fission and fusion) are required to withstand extreme environments. Depending on the component’s function they may be exposed to a number of demands such as high levels of radiation, temperature, pressure etc. Future generation nuclear power plants aim to increase output and efficiency...
Conference Paper
Full-text available
Finite element methods (FEM) modelling of materials with complex microstructures is typically achieved by homogenisation and applying effective material properties. This work investigated the use of a technique whereby 3D X-ray tomography images of such materials are converted directly into image-based FEM (IBFEM) models. In this instance IBFEM was...
Conference Paper
Full-text available
Nuclear materials are subjected to demanding environments, encountering high temperature gradients and fast neutron fluxes that gradually damage its structure and therefore change the material properties. Some components of a nuclear reactor determine its lifetime , such as the graphite core and steel pressure vessel for fission reactors. In case o...
Article
Full-text available
The extreme environments found within the nuclear sector impose large safety factors on modelling analyses to ensure components operate in their desired manner. Improving analysis accuracy has clear value of increasing the design space that could lead to greater efficiency and reliability. Novel materials for new reactor designs often exhibit non-...
Article
Full-text available
As-received and annealed tungsten samples were irradiated at a temperature of 400 °C with Re and W ions to peak concentrations of 1600 appm (atomic parts per million) and damage levels of 40 dpa (displacements per atom). Mechanical properties were investigated using nanoindentation, and the orientation and depth dependence of irradiation damage was...
Presentation
Full-text available
The extreme environments found within the nuclear sector will be even more demanding as future generation power-plants strive for further efficiency and increased output. It is required that components not only withstand such conditions but operate in their desired manner, thus large safety factors are imposed on modelling analyses. Improving analy...
Conference Paper
Full-text available
Explicit strategies for the solution of finite element problems, such as crash simulation, scale well on computing platforms with thousands of cores. In contrast, it is a widely held view that implicit analysis is not suited to parallel computing. The purpose of this paper is to challenge that belief. The open source parallel finite element softwar...
Article
Full-text available
The thermal performance of a carbon fibre composite-copper monoblock, a sub-component of a fusion reactor divertor, was investigated by finite element analysis. High-accuracy simulations were created using an emerging technique, image-based finite element modelling, which converts X-ray tomography data into micro-structurally faithful models, captu...
Conference Paper
Full-text available
The authors are the lead developers in the ParaFEM project. ParaFEM is an open source platform for parallel finite element analysis that builds on the serial codes provided with the text book Smith, Griffiths and Margetts “Programming the Finite Element Method”, 5th Edition, Wiley, 2014. The latest version of the code provides parallel programs for...
Article
Full-text available
This work investigates the thermal performance of four novel CFC–Cu joining techniques. Two involve direct casting and brazing of Cu onto a chromium modified CFC surface, the other two pre-coat a brazing alloy with chromium using galvanisation and sputtering processes. The chromium carbide layer at the interface has been shown to improve adhesion....
Presentation
This work presents ongoing software development activities that are being carried out to enable the predictive modeling of components in both Nuclear Fission and Fusion reactors. Of particular interest is the role material micro-structures play in controlling the performance of engineering materials under extreme conditions. Our models are derived...
Presentation
PARAFEM: Open source software for predictive modeling of nuclear materials with spatially variable properties and complex architectures
Conference Paper
Full-text available
This paper describes progress in the development of open source parallel finite element software for solving time-dependent heat flow problems with billions of degrees of freedom. The motivation comes from the need to characterize the bulk thermal properties of composite materials employed in nuclear fission and nuclear fusion reactors. The modell...
Poster
Simulating thermal diffusivity of a SiCf/SiC composite for fusion applications using a finite element model created from an x-ray tomographic image
Article
Full-text available
In interdisciplinary subjects such as fusion energy, training PhD students is a complex task. Llion Marc Evans describes how being part of the Fusion Doctoral Training Network has helped him develop as a researcher.

Network

Cited By

Projects

Project (1)
Project
https://ibsim.co.uk/events Our aim is that the activities of IBSim-4i will facilitate a wider adoption of image-based simulation and provide a platform to discuss the cutting-edge developments in the field. These series of events will be the ideal forum for the fostering of ideas and the establishing of new collaborative links, helping to build strong networks within UK and at an international level. The event is intended for academic researchers and industry professionals interested in learning about applications of image-based simulation in manufacturing and new exciting ways it may be coupled with machine learning to drive digital twin technology.