Development and Improvement Of Numerical methods and Tools for modelling coupled processes (DONUT)

‘What’

This WP will develop and improve specific numerical methods and tools that allow efficient modelling coupled processes, considering (i) the versatility of numerical methods with regards to the various tools used by “end-users”; and (ii) a demonstration of robustness and added-value of developments by benchmark of the methods and tools on representative test cases at large repository time and space scales.

‘Why’

The DONUT WP has been selected for the first phase of EURAD as it will address the following activities identified as a high or medium level of common interest in Theme 7 “Performance assessment, safety case development and safety analyses” of the Roadmap: 

• Improved understanding of the upscaling of THMC modelling for coupled hydromechanical-chemical processes in time and space (Phase 1 of the Roadmap). 
• Improved understanding and models for the impact of THMC on the behaviour of the host rock and the buffer materials (Phase 2 of the Roadmap).
• Improved multi-scale reactive transport models (Phase 2 of the Roadmap)
• Improved performance assessment tools (Phases 0 and 1 of the Roadmap).
• Further refinement of methods to make sensitivity and uncertainty analyses (Phases 2 and 3 of the Roadmap)
• Improved computing (Phases 3 and 4 of the Roadmap).

Furthermore, by improving the numerical methods and tools that are able to manage multi-physicals coupled processes, the work conducted in this WP is relevant for better description of site evolution and design optimization. Both can be applied to deep geological and near surface radioactive waste disposal. Finally, by providing efficient numerical means for analysis, DONUT will, contribute to abstraction for safety case (quantification of safety margins, detailed assessment of safety functions allocated to components…).

Major highlights (June - Nov 2022)

- A joint ACED, BEACON, DONUT & MAGIC contribution entitled “MODELLING OF THE LONG-TERM EVOLUTION AND PERFORMANCE OF ENGINEERED BARRIER SYSTEM” has been published in the special issue “Euratom Research and Training in 2022: challenges, achievements and future perspectives” of EJP Nuclear Sciences & Technologies.
- DONUT WP board has been actively involved in the launching of a collection entitled “Digitalisation for Nuclear Waste Management: Predisposal and Disposal” in Environmental Earth Sciences journal. (https://link.springer.com/collections/jfaighjcji). 

Forward look

- Contributing through opinion or research paper to the “Digitalisation for Nuclear Waste Management: Predisposal and Disposal” collection

- Continue to stimulate exchanges during the WP DONUT annual meeting that will be held beginning of  2023 (date under clarification)