eMEANSS Work Packages
Work Package 1 - Reactor Physics
UK lead: Prof. Parks and Prof. Nuttall
India lead: Dr. Umasankari
Using benchmark PWR LOCA as a basis for investigations…
WP1.1 – Determine whether two independent teams arrive at similar conclusions.
WP1.2 – More fully understand the ways in which multiple uncertainties can cascade, hence give rise to different whole-system outcomes.
WP1.3 – Identify a set of isotopes and neutron energies for which nuclear data uncertainty should be reduced. This will be used as a pointer to a planned future Round VI Indo UK project dedicated specifically to ‘nuclear data’.
WP1.4 – Increase understanding the importance of thermal (Doppler) effects in reactor physics uncertainties – this will relate back to the Round VI nuclear data plans.
Work Package 2 - Structural Component Integrity
UK lead: Prof. Marrow
India lead: Dr. Khan
WP2.1 – Utilise the Electro-Thermal Mechanical Testing (ETMT) at the UK Diamond Light Source (beamline I12 and DIAD) to design and conduct critical experiments, using X-ray diffraction and digital image correlation of radiographs, that simultaneously study, in situ, the interactions between cyclic load and temperature (up to 1000°C).
WP2.2 – Develop an Abaqus UMAT that describes data from Task 1, on the stress and strain relationships in advanced nuclear graphites, developed by Dr. Khan at BARC. Numerical studies will be conducted (at BARC) to predict useful service life of some of the critical core components of Indian HTRs. Using state-of-the-art Monte-Carlo methods, Oxford/Bristol will then assess the potential effects of scatter in non-linear properties and the uncertainties associated with the load sequencing on the safety margin.
WP2.3 – Implement a new framework for uncertainty modelling using the outputs from working with the outputs of WP2.1 and WP2.2, and develop a simplified engineering model for fatigue life assessment. The work will be done with non-irradiated graphite, but will develop a methodology that could be applied to irradiated graphites in due course.
Work Package 3 - Nuclear Fuel Performance
UK lead: Dr. Middleburgh
India lead: Dr. Khan
WP3.1 – Complexities in predicting fuel performance arise once fuel is operated vs fresh fuel. These will thus be reviewed and a statistical approach adopted to address the various uncertainties arising especially at high discharge burn-up, particularly when crudding of the fuel is evident.
WP3.2 – A similar methodology will be applied to (U,Gd)O2 fuel, as such doped fuels are being used in commercial reactors to provide suppression of activity at the beginning of operational life. Considering the paucity of test data and limitations in existing models, higher safety margins are currently adopted. In this task density functional theory (DFT) will be employed to develop accurate potential functions that can be used for higher scale simulations. The impact on uncertainty that such multi-scale methods have, will help to reduce the need for expensive in-reactor experiments and post-irradiation examinations (PIE).
WP3.3 – This multi-scale methodology will then be applied to a commercially untested fuel. The UK team will focus on composite fuels (e.g. TRISO). Continuum-scale models will be generated using state-of-the-art understanding gained from other fuels already accepted for commercial operation. Targeted testing will then be proposed, which will be determined using the uncertainty analysis methodology developed for both UO2 and (U,Gd)O2.
Work Package 4 - Synthesis and Dissemination
UK leads: Dr. Patelli and Prof. Nuttall
India lead: Dr. Gupta and Dr. Prasad
WP4.1 – Identify, build and share commonalities, and the linkages between different models and methods developed in WP1, 2 and 3.
WP4.1 – Through this WP, the dissemination and clear communication of methods to industry and the general public will also be undertaken.