Analyses of design extension conditions without significant fuel degradation for operating nuclear power plants: An OECD/NEA review

• Published in: Nuclear engineering and design Vol. 425; p. 113320
• Main Authors: Zhang, J., Havet, M., Zheng, J., Bousbia Salah, A., Ševeček, M., Kral, P., Krhounkova, J., Guba, A., Hozer, Z., Bersano, A., Mascari, F., Cherubini, M., Nemec, T., Sánchez, M., Mendizábal, R., Queral, C., Herranz, L.E., Adorni, M., Bales, M.
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 15.08.2024
• Subjects: Design extension conditions; Deterministic safety analysis; Good practices; Probabilistic safety analysis; Safety improvement; DBA; LOCA; WENRA; SLB; DSA; OECD; IAEA; BEPU; SBLOCA; WGRISK; Safety improvement; FSAR; PSA; EUR; PWR; STGR; WGAMA; PKL; R&D; TSO; WGFS; ELAP; IET; SMR; Probabilistic safety analysis; MSTGR; DiD; CFD; PCT; NPPs; Good practices; BE; OAT; SET; Design extension conditions; ATLAS; ATWS; RHRS; SIPs; AOO; LBLOCA; SBO; DEC; CCF; NEA; TH; POSRVs; RLs; Deterministic safety analysis
• ISSN: 0029-5493; 1872-759X
• DOI: 10.1016/j.nucengdes.2024.113320

•Review of the EUR, WENRA, and IAEA definitions and requirements of the DEC-A analysis;•Review of the current level of knowledge and modeling capabilities for DEC-A relevant phenomena;•Review of good practices for DEC-A analysis in OECD/NEA member countries and partners. Since 2012, many NEA member countries have implemented deterministic safety analyses for operating nuclear power plants under design extension conditions without significant fuel degradation or core melt (DEC-A). However, variations persist among these countries in defining DEC-A scenarios and acceptance criteria, validation and application of computer codes, development and application of deterministic safety analysis methods. Furthermore, there is a dearth of shared international experience and methodologies among various stakeholders, including regulatory authorities, technical safety or support organizations, utilities, engineering and consulting companies. To address these gaps, the OECD/NEA initiated a project in 2021, titled “Good Practices for Analyses of Design Extension Conditions without Significant Fuel Degradation for Operating Nuclear Power Plants” (or “DEC-A”), under the auspices of the Working Group on Accident Management and Analysis (WGAMA) and the Working Group on Fuel Safety (WGFS). The DEC-A project aims to review and summarize the current requirements, knowledge status, and best practices in NEA member countries. This paper outlines the objectives and scope of the OECD/NEA DEC-A project, and presents the findings from the review and discussions for each task.