Dr K P Travis

Dr Karl P Travis

Reader in Computational Physics and Nuclear Waste Disposal

Telephone: +44 (0) 114 222 5483
Fax: +44 (0) 114 222 5943
Email: k.travis@sheffield.ac.uk

Address: Department of Materials Science and Engineering
Sir Robert Hadfield Building, Mappin Street, Sheffield, S1 3JD

Karl joined the Department in 2003 from the University of Bradford, where he was the A. H. Marks Lecturer in Physical Chemistry 2000-2. Before that he undertook postdoctoral appointments at Imperial College (with Dr David Nicholson), North Carolina State and Cornell Universities (with Prof Keith Gubbins) and the Australian National University (with Prof Denis Evans). He obtained both his PhD and BSc in Chemistry from UMIST, where he also won the Reynolds Prize, UMIST´s premier undergraduate prize.

Professional activities and recognition

  • Member of the Royal Society of Chemistry Statistical Mechanics and Thermodynamics Group (2011 – present)
  • EPSRC Peer Review College Member
  • Co-organiser of Joint CCP5-RSC Workshop: Advances in Theory and Simulation of non-equilibrium Systems, Imperial College, London (2013).
  • Co-organiser of inaugural “ NEMD School” to be held annually, starting 2014 at Imperial College London.

Research themes

Alternative Disposal Concepts: Deep Borehole Disposal
Geological disposal of HLW and spent nuclear fuel (SNF) in very deep boreholes is a concept whose time has come. The alternative – disposal in a mined, engineered repository is beset with difficulties not least of which are the constraints placed upon the engineered barriers by the high thermal loading.
The deep borehole concept offers a potentially safer, faster and more cost-effective solution. The deep borehole research group at Sheffield (Travis and Gibb) is at the forefront of international efforts to develop this concept. We are currently working with Sandia National Labs on a program leading to the drilling of pilot borehole in the USA. Our work includes: developing sealing and support matrices, rock welding and deployment mechanisms, and employs a combination of experiment and continuum modeling (Finite differences and Smooth Particle Applied Mechanics).

Behaviour of Materials under extreme conditions
Our main focus here is on wasteform performance. The detrimental effects of self-irradiation (mostly alpha decay) of immobilised radionuclides include: swelling, amorphisation and crack formation in ceramics and de-vitrification in glasses. We use computational methods (mainly molecular dynamics and topological modeling) and statistical mechanics to examine the consequences of alpha recoil damage and understand the recovery pathways in these materials. Recent research is aimed at understanding why some materials have a greater resistance to radiation-induced amorphisation. The use of Smooth Particle Applied Mechanics in understanding how materials fail under mechanical and thermal loading is another area of interest.

Simulation Methodology
Software Packages certainly have a role to play in the Materials Science and Engineering community, but new research often requires new methods of simulation that are not supported by off-the-shelf codes. Developing new simulation methods and codes is a key area of interest for this research group.
Previous research in this area includes the development of configurational thermostats and barostats for molecular simulation and a method which allows an unambiguous determination of the role played by intramolecular flexibility on transport properties of liquids. Recent work in collaboration with Bill and Carol Hoover, has lead to a new algorithm for simulating Joule-Thomson expansion of gases.

Postdoctoral research associates
Dr Nick Collier (Development of a geothermal cement for use in Deep Borehole Disposal)

PHD Students

  • Mr James Miller (Predictive models for glass viscosity)
  • Miss Emma Pyle (Modelling microstructure of Nickel based superalloys)
  • Mr Chris Williams (Multiscale modeling of a pertechnetate-SAMMs adsorbent)
  • Mr Zakk Griffiths (Modelling radiation damage in glass-ceramic composites)
  • Mr Nikos Galanakis (Modelling radiation damage in iron phosphate glasses)
  • Mr Adam Squires (Mathematical modeling of waste package deployment rates)
  • Mr Matthew Killeen (Modelling clogging of sand filters by colloids)

Recent publications

  • Patrick Brady, Susan Altman, Palmer Vaughn, Dennis Nielson, Joon Lee, Fergus Gibb, Paul Mariner, Karl Travis, William Halsey, John Beswick, and Jack Tillman, ”Deep Borehole Disposal Research: Demonstration Site Selection Guidelines, Borehole Seals Design, and RD&D Needs”, Report to US Department of Energy. SAND2013-9490P (2013).
  • K. P. Travis and T. Hiddleston, “Multiscale Modelling of Material Failure using Particles” , Molecular Simulation 40, 141-153 (2014).
  • W. G. Hoover, C. G. Hoover and K. P. Travis, “Shockwave compression Joule-Thomson Expansion”, arXiv:1311.1717 , (2013).
  • Gunther M, Jivkov AJ, Travis KP, “Site-bond modelling of porous quasi-brittle media”, Mineralogical Magazine, 76, 2969-2974 (2013).
  • Gibb FGF, Travis KP, “Deep borehole disposal of higher burn up spent nuclear fuels”, Mineralogical Magazine, 76, 3003-3017 (2013).
  • H. R. Foxhall, K. P. Travis, L. Hobbs, S. Rich and S. Owens, “Understanding the radiation-induced amorphization of zirconolite using molecular dynamics and connectivity topology analysis” Philosophical Magazine , 93, 328-355 (2013).
  • C. Braga and K. P. Travis, “Computer simulation of the role of torsional flexibility on mass and momentum transport for a series of linear alkanes”, J. Chem. Phys., 137 , 064116 (2012).
  • Gunn DSD, Allen NL, Foxhall H, Harding J, Purton JA, Smith W, Stein MJ Todorov, IT and Travis KP, “Novel potentials for modelling defect formation and oxygen vacancy migration in Gd2Ti2O7 and Gd2Zr2O7 pyrochlores”, J. Mat. Chem., 22, 4675-4680 (2012).