Members of FIDES-II meeting in France. Photo: CEA.
Members of the Second Framework for Irradiation Experiments (FIDES-II) joint undertaking gathered on 7-11 April 2025 in Aix-en-Provence, France, for the Technical Advisory Group and Governing Board meetings hosted by CEA (Commissariat à l'Énergie Atomique et aux Énergies Alternatives). The FIDES-II Framework aims to ensure and foster competences in experimental nuclear fuel and structural materials in-reactor experiments through a diverse set of Joint Experimental Programmes, JEEPs.
The latest FIDES-II meeting gathered more than 100 members of the consortium coming from 13 countries and the European Commission.
The main focus of the meeting was the review of the process of the ongoing JEEPs. The second three-year term of the Framework, which started in April 2024, has nine ongoing JEEPs:
- P2M aiming to perform power ramp experiments;
- HERA and LOC-HBU performing accident simulations;
- INCA and MCA-ATF with cladding irradiations to study irradiation creep;
- ATOMIC to investigate various novel fuel forms;
- INCREASE phases 1 and 2 to irradiate light water reactor structural materials; and
- HITEC to irradiate advanced reactor structural materials.
First irradiations of cladding materials and reactivity tests for fuel have been performed in previous years, and the year 2025 will see the start of several in-reactor experiments.
The Framework has several cross-cutting activities that are carried out concurrently to the experiments. Modelling and simulation activities are actively pursued within projects, with the exercises using non-proprietary data also open to participants outside of FIDES-II community. An Instrumentation Centre of Expertise has been established under FIDES-II, and the group has begun a fruitful collaboration to support the instrumentation needs of various experiments. As the in-core experiments rely on specialised instrumentation capable of performing in challenging conditions, the international collaboration was set up to share experiences and best practices amongst the research reactor operators. The group has already addressed several topics and is meanwhile considered vital to get the best out of the experiments.
Technical tour of the meeting included a visit to Jules Horowitz Reactor currently under construction. Photo: CEA.
In addition to the technical discussions, the meeting included a tour of several nuclear safety related experimental facilities at CEA’s Cadarache site. These included tours at LECA-STAR hot cells, where test segments used in P2M power ramps are being manufactured, as well as Jules Horowitz Reactor construction site, the CABRI reactor and the PLINIUS experimental facilities for investigating severe accidents.
This meeting also marked the start of preparations for the next FIDES-II term, due to begin in early 2027. Fifteen project ideas were presented to the Technical Advisory Group, and these will be developed into the proposed Programme of Work during the next year. The proposed projects would both continue the ongoing research, as well as extend the current work to cover new topics and new research reactors.
