These activities are of crosscutting nature addressing both Light Water Reactors (LWRs) as well as Small Modular Reactors (SMRs) and Generation IV systems.
The JRC uses a set of numerical tools to study the safety of current operating LWR as well as innovative reactor designs (Generation IV and SMRs). These studies include core physics assessment with MCNP and CFD calculations of specific components, system analysis performed with RELAP and TRACE and Severe Accident (SA) simulations using ASTEC and MAAP codes. Historical experimental data on SA are stored in the STRESA database that belongs to the JRC.
Laboratory scale studies using miniaturised and accelerated testing are important to predict the structural integrity, the safe performance of reactor components as well as screening new nuclear material for advanced applications. The experimental campaigns in the JRC EMMA laboratories allows for translating materials degradation mechanism into component ageing and its impact on plant life management for both current operating LWRs as well as innovative reactor systems. The materials data produced by the JRC are stored in JRC’s material database MatDB.
Safety and Long-term operation of Light Water Reactors (LWR)
Those European countries keeping nuclear power in their energy mix are aiming at operating their Nuclear Power Plants (NPPs) longer than their initial planned life and to maintain high safety standards, licensees continuously refurbish and modernize their NPPs to meet strict regulatory requirements. They implement aging management programs to address the degradation of passive structures, systems, and components (SSCs), as well as In-Service Inspection (ISI) procedures to detect flaws in these components early. These programs are continuously improved based on research and development programs and initiatives.
The experimental campaigns of the JRC's AMALIA (Aging of Materials and Life Assessment) laboratory are aimed at identifying degradation and mitigation mechanisms of SSCs, to test and screen advanced cladding materials, coatings as well as test pieces produced with advanced manufacturing techniques for resistance to combined corrosion, thermal, and mechanical loads. The AMALIA results are incorporated into practices for lifetime assessment, ISI, and codes and standards.
The JRC activities align with the needs of member states represented in SNETP - NUGENIA, and contribute to strategic documents, position papers, technical reports, and guidance & best practice documents, such as ENIQ Recommended Practices.
The JRC conducts also research on severe accident management, focusing on uncertainty analyses for improving the ASTEC code, which is the reference computational tool.
Innovative Reactor Systems (SMRs, Generation IV)
Small Modular Reactors (SMR), are increasingly receiving attention worldwide as potential contributors in helping climate change mitigation and improving energy security in combination with renewable and other energy sources. Many SMR designs are LWR and Generation IV type and propose enhanced safety features together with attractive technical and economic characteristics, provided by compact and integrated designs, innovative materials, components and manufacturing techniques, all of which are yet to be qualified in view of licensing. The JRC studies on SMRs address the safety of various types of SMRs (water, gas, liquid metal and molten salt cooled) taking into account their reduced power level and individual design specifics.
The deployment of innovative reactors requires standardisation efforts that are accompanied by pre-normative research. As an example, the JRC collaborates into pre-normative research activities with its Liquid Lead Laboratory (LILLA) to harmonise testing procedures and produce materials data needed for the needed update of the design codes.
The JRC activities in this field are aligned with the roadmaps of SNETP-ESNII and NC2I as well as EERA JPNM and GIF and will be of interest to the recently created Industrial Alliance. Feasibility and impact of non-electric applications of SMR, strategic input to committees in SNETP, GIF, IAEA and OECD/NEA has been delivered.
Materials Deployment Acceleration Platform
The deployment of new materials or new manufacturing technologies as well as innovative reactor designs require pre-normative research to improve the design codes and allow for their licensing. However, standard qualification procedures are costly and require several tens of years until a specific material or component is fully qualified. In order to reduce time and costs a materials acceleration platform that includes standard and new test methods, AI driven data reduction schemes and models are developed.
The JRC approach foresees to bridge time and length scale through sample miniaturisation and mechanistic evaluation of materials behaviour. The experimental suite includes small punch, nano-indentation and in-situ indentation in combination with plasma-FIB/SEM dual beam. Development of advanced testing methods simulating reactor conditions as the membrane bulge tests with digital image correlation (TRIAS) or LILLA are also part of the platform. Complementary analytical and numerical simulations help translate results from small scale to component scale.
The experimental/numerical platform is part of the Open Access scheme, hosting visiting scientists from member states to perform research using JRC infrastructure and technical support and is fully embedded in the Co-funded European Partnership for research in nuclear materials.