NEA CFD-Task Group members at a meeting in Chatou, France on 10-11 June 2025.
The Computational Fluid Dynamics (CFD) of the NEA Working Group on Analysis and Management of Accidents (WGAMA) completed its 6th phase on 10-11 June 2025 with a meeting in Chatou, France. The event, hosted by EDF, gathered nearly 40 experts from 13 countries to discuss activities related to the expanded use of CFD for nuclear reactor safety.
During the meeting, the group discussed the importance of data preservation. Large volumes of experimental data are needed to support the safe operation of nuclear installations. The application of CFD introduces new and more stringent requirements for experimental data. Therefore, it is essential to identify and assess databases that can support the validation of CFD codes, ensuring their relevance and applicability to nuclear safety applications. This effort will be carried out together with the ongoing update and expansion of the CSNI Code Validation Matrix (CCVM).
The task group also discussed the next workshop on computational fluid dynamics for nuclear power plant safety: the CFD4NRS-10. This activity aims to establish a forum where numerical analysts, modelers and experimentalists can exchange information on CFD applications for nuclear safety and advanced reactor issues. This workshop will be co-organised with the Japan Atomic Energy Agency (JAEA) and will be held in Mito, Japan on 10-12 December 2025.
Following discussions, the group finalised a brochure for system code users, the second in a series of three. These technical documents aim to enable end users to assess whether the CFD approach is appropriate.
Finally, results of the open and blind phase of the benchmark and experimental validation on thermal mixing and fatigue in a T-junction with a dead leg were presented and discussed among the participants. At the end of the meeting, participants visited the dead legs experiments in Chatou EDF Lab.
