Participants of the WGAMA meeting held in Cadarache, France, on 9-11 September 2024.
The NEA Working Group on the Analysis and Management of Accidents (WGAMA) held its annual meeting in the south of France from 9-11 September 2024, hosted by the CEA (the Alternative Energies and Atomic Energy Commission). Nearly 90 delegates from 19 member countries, along with representatives from the International Atomic Energy Agency (IAEA) and the European Commission, attended.
During the meeting, the group discussed progress on 16 ongoing activities related to nuclear thermal-hydraulics, computational fluid dynamics (CFD) for reactor safety, and severe accidents. Key achievements included the completion of four reports on topics such as:
- analyses of design extension conditions without significant fuel degradation (DEC-A) for operating nuclear power plants, with the (WGFS).
- reactor pressure vessel integrity assessments for in-vessel retention (IVR), with the Working Group on Integrity and Ageing of Components and Structures (WGIAGE).
- applicability of uncertainty quantification methodologies to CFD in the context of nuclear reactor safety studies; and
- a state-of-art-report on the behaviour of combustible gases in severe accidents.
The group also introduced the first of a brochure series, CFD for Deciders, aimed at helping organisations that are new to CFD.
Additionally, the group reviewed proposals for a workshop on passive system performance and a key update and extension of the CSNI Code Validation Matrix for reactor thermal-hydraulic phenomena.
Discussions should continue on how to ensure a more integrated approach in the thermal-hydraulics area, considering proposals for collaborative research, such as the new SYStem THERmal hydraulics (SYSTHER) joint project proposal to address thermal-hydraulic nuclear safety priorities for both existing and advanced reactor designs, including small modular reactors.
Due to the growing worldwide interest in accident-tolerant fuel concepts and the lack of knowledge of the impact of chromium on fission product behaviour under severe accident conditions, a new joint project proposal, called FORESEEN (for fission products behaviour under severe accident with new fuel concepts), was discussed.
CEA and IRSN meeting participants. Credit: S. Poulain CEA
Tours of the CEA and the IRSN (Institute for Radiation Protection and Nuclear Safety) sites in Cadarache included visits to the platforms PLINIUS on severe accidents, THEMA on thermal hydraulics and CHROMIA on fission products.
From left to right: H. Nakamura (JAEA) and F. Barré (IRSN). Credit: S. Poulain CEA
Finally, the group thanked François Barré after a long career dedicated to nuclear safety research, for his commitment to the NEA activities, including as co-chair and bureau member of the WGAMA.
For more information on the working group, click here.
