Integral Pressurized Water Reactor (iPWR) are ready to be licensed as new builds because they start from the well-proven and established large Light Water Reactor (LWR) technology, incorporate their operational plant experience/feedback, and include moderate evolutionary design modifications to increase the inherent safety of the plant. However, despite the reinforcement of the first three levels of the Defence-in-Depth (DiD), e.g. with the adoption of passive safety systems, a sound demonstration of iPWR ability to address Severe Accidents (SA) should be carried out (DiD levels 4-5). Therefore, some scenarios that could lead to SAs need to be postulated and deterministically studied. Therefore, the systematic analyses of the applicability and transfer of the current available SA experimental database (developed for current large-LWR) for iPWR safety assessment studies, and the analyses of current codes capabilities to simulate SA phenomena in iPWR are novel topics of current high interests.
In this framework, the key objective of the SASPAM-SA project is to investigate the applicability and transfer of the operating large-LWR reactor knowledge and know-how to the near-term deployment of iPWR, in the view of SA and Emergency Planning Zone (EPZ) European licensing analyses needs.
Key Outcomes of SASPAM-SA :
- To be supportive for the iPWR licensing process by bringing up key elements of the safety demonstration needed;
- To speed up the licensing and siting process of iPWRs in Europe.
The achievement of the overall elements is assured by a consistent and coherent work programme, reflected in the technical Work Packages (WP) structure:
WP1- Coordination;
WP2- Input deck development and hypothetical SA scenarios assessment (SCENARIOS);
WP3 - Applicability and Transfer of the Existing SA experimental database for iPWR Assessment (EXP);
WP4 - Assessment of code capabilities to simulate and evaluate corium retention in iPWRs (IVMR);
WP5 - Assessment of the code capabilities to simulate IPWR containment and characterize mitigation measures efficiency (CONT);
WP6 - Characterization of iPWR EPZ (EPZ);
WP7 - Communication, dissemination and exploitation (DISSE).
In order to maximize the knowledge transferability and impacts of the project two generic design-concepts, characterized by different evolutionary innovations in comparison with larger operating reactor, have been selected for the analyses: a) IPWR characterized by a submerged containment and electric power of about 60 MWe, called design 1; b) IPWR characterized by the use of several passive systems, a dry containment and an electric power of about 300 MWe, called design 2.These two generic reactor concepts include the main iPWR design features, considered in the most promising designs ready to go on the European market, allowing to assess in a wider way the capability of codes (SA and CFD) to simulate the phenomena typical of iPWR. It is not the project’s objective to assess the generic reactor designs selected but, based on the project findings, allow a more general statement on the code’s applicability to currently favored designs under postulated SA conditions.
