The Strategic Research Agenda (SRA; https://www.ejp-eurad.eu/publications/
eurad-sra) of the European Joint Programme on Radioactive Waste Management
(EURAD; https://www.ejp-eurad.eu/) describes the scientific and technical
domains and sub-domains and knowledge management needs of common
interest between EURAD participant organizations. Theme number 7 is
entitled “Performance assessment, safety case development and safety
analyses.” A list of research and development priorities and activities of
common interest to be addressed within EURAD for theme 7 have been established. Amongst others, the Understanding and modelling of multi-physical
Thermo-Hydro-Mechanical-Chemical coupled processes (THMC) occurring in
radioactive waste disposal is a major and permanent issue to support
optimization of design and safety case abstraction. To tackle this challenge a
research work package entitled “DONUT: Development and improvement of
numerical methods and tools for modelling coupled processes” has been
conducted within the EURAD join programming initiative. The purpose of this
work package is to improve/develop methods or numerical tools in order to go a
step further in development of (i) relevant, performant and cutting-edge numerical
methods that can easily be implemented in existing or new tools, in order to carry
out high-performance computing to facilitate the study of highly coupled
processes in large systems, (ii) numerical scale transition schemes for coupled
processes, (iii) innovative numerical methods to carry out uncertainty and sensitivity
analyses. In this paper the work carried out within the DONUT work package is put
in perspective regarding the existing concept and literature on the field. It does not
pretend to be exhaustive but rather to put emphasis on particular issues tackled
during the project.