Fusion Engineering CDT

Award details

Tritium Breeding Blankets (BBs) are mission-critical in-vessel components in fusion reactors, responsible for breeding tritium, extracting heat, and shielding downstream structures from high-energy neutrons. The success of commercially viable fusion energy will depend heavily on these blankets maintaining their structural and functional integrity over the design lifetime under extreme operating conditions. However, conventional deterministic methods are inadequate for ensuring their reliability, as neither the necessary material property data nor validated empirical safety factors are available for the representative 14 MeV neutron environment—and such data are unlikely to become available in the next around 10 years.

We will investigate the probabilistic approach as a much faster and reliable alternative for structural integrity assessment of BBs. Although the merits of probabilistic schemes for fusion design have been recently identified, the available literature remains at primitive stage - a rigorous comparison between probabilistic and deterministic strategies for real fusion components is missing. Our aim is to devise a probabilistic framework for BB design where brittle fracture due to ductility exhaustion can become enormously sensitive to irradiation dose and manufacturing defects. A particular challenge for BBs is that due to the very large number of modules required in a reactor (above 4000), the probability of brittle fracture amongst all modules can be relatively large even if the probability of brittle fracture in each individual module is low.

We will perform Bayesian/Weibull statistical analysis to address the limited amount of irradiation data for reduced-activation steels at different dpa (for which simple statistical averaging is currently dangerous). We will derive probability density functions associated with material property distribution and thermal-mechanical load distribution at critical BB compartments, e.g. first wall and pressure tubes. We will perform defect tolerance analysis by assuming pre-existing surface defects of statistical size/orientation at critically stressed locations – this will involve the calibration of probability density functions based on existing fracture toughness data (stress intensity) at different dpa and manufacturing data (probability of flaw size). We eventually determine brittle failure probability at critically stressed regions as a function of the uncertainties induced by material-manufacturing-load environment. This will provide essential physical, statistical and computational pointers for developing new design standards as well as developing fusion alloys through design-informed experiments.

The student will enjoy the opportunity to develop strong theoretical and computational modelling skills in solid mechanics and to collaborate with PhD students working in Finite Element modelling of HCPB breeding blankets. Please contact Dr Christos Skamniotis for informal queries about the project. 

This EngD project is funded by the Fusion Engineering CDT and hence the student will be based at Kings College London but should expect to engage fully with the 3-month training programme within the Fusion Engineering CDT at the start of the course. CDT training will be delivered across the CDT partner universities at Sheffield, Manchester, Birmingham and Liverpool. There is also expectation of an up to 6-month work placement at UKAEA, specially aligned to the objectives of this project. For further information about the CDT programme, please visit the website https://www.fusion-engineering-cdt.ac.uk/ or send an email to hello@fusion-engineering-cdt.ac.uk.

Tags: Fusion_cdt

Award value

• Stipend: Tax-free stipend of approximately; £22,780 p.a. with possible inflationary increases after the first year.;
• Tuition fees: UK Home tuition fees 25/26 £5,006 per year
• Bench Fees: TBC

These tuition fees may be subject to additional increases in subsequent years of study, in line with King's terms and conditions.

Other (please outline): Funding for 4 years. Note: A fully funded studentship will only cover what is listed above. Applications should be aware there may be other costs which will not be covered by the studentship, for example, visa fees, healthcare surcharge, relocation costs.

Eligibility criteria

Funding covers UK student tuition fees only.

International candidates are welcome to express interest to Dr Skamniotis and may be eligible for this opportunity, subject to case-by-case assessment of their circumstances and suitability. 

Application process

To be considered for the position candidates must apply via King’s Apply online application system.

Details are available at https://www.kcl.ac.uk/engineering/postgraduate/research-degrees

Please apply for Engineering Research (MPhil/PhD) and indicate Christos Skamniotis as the supervisor and quote the project title in your application and all correspondence.

Please apply for Engineering Research (MPhil/PhD) and indicate Christos Skamniotis as the supervisor and quote the project title in your application and all correspondence.

Please ensure to add the following code [EPSRCEng50%2506/Industry] in the Funding section of the application form.

Please select option 5 ‘I am applying for a funding award or scholarship administered by King’s College London’ and type the code into the ‘Award Scheme Code or Name’ box. Please copy and paste the code exactly.

The selection process will involve a pre-selection on documents and, if selected, will be followed by an invitation to an interview. If successful at the interview, an offer will be provided in due course.

Further information can be found at https://www.kcl.ac.uk/study/postgraduate-research/how-to-apply

Please contact:

christos.skamniotis@kcl.ac.uk for queries about the project.

If you require support with the application process, please contact pgr-engineering@kcl.ac.uk