The main objective of the SOTERIA project is to enable nuclear power plant operators, as well as regulators, to better understand and thereby predict the ageing phenomena occurring in reactor pressure vessels and internal steels in order to ensure a safe long-term operation of existing European nuclear power plants.
SOTERIA will thus provide further knowledge and tools to manage the ageing of nuclear power plants by addressing 4 specific technical objectives:
- Carry out experiments assessing neutron flux and fluence effects on reactor pressure vessels and internal steels in pressurised water reactors
- Evaluate the residual lifetime of reactor pressure vessels by taking into account metallurgical heterogeneities
- Assess the effect of the chemical and radiation environment on embrittlement in internals
- Develop models for the assessment of ageing mechanisms in RPV and internals and set of an integrated computer-based platform including the new modelling tools
Besides these technical objectives, SOTERIA also has an educational objective which is to communicate on the project achievements towards the nuclear engineering and research community in order to improve and harmonise the knowledge of ageing phenomena in nuclear power plants. The planned educational activities will be carried out through workshops and training sessions organised during the project.
SOTERIA expects to deliver the following results:
- A deeper understanding of initial microstructure heterogeneities effects on fracture models and radiation-induced degradation of reactor internal steels
- A database collecting the results from the experiments carried out in the project (microstructural characterisation such as defects cluster density/size/shape, chemical segregation, or mechanical properties)
- Guidelines on the integration of experimental data in modelling tools
- Models simulating the evolution of the irradiated microstructure and the mechanical behaviour, taking into account flux effect to transfer radiation-induced phenomena observed in accelerated irradiation facilities towards structural components during service life
- A modelling platform embedding improved ageing models for reactor structural components
- A specific industry-adapted version of the modelling platform to support the evaluation of reactor safety margins, assessed in a user environment
- Guidelines for better use of modelling, material testing reactors, and surveillance data in the prediction of radiation-induced ageing phenomena
In other words, the knowledge and tools generated in SOTERIA will contribute to improve the European nuclear safety policy, to increase the leadership of the EU in safety related equipment and information, as well as to enhance the safety of nuclear power plants worldwide.