In 1991 the OECD published the first State-of-the-Art Report (SOAR) on In-Vessel Core Degradation, NEA/CSNI/R(91)12, updated to June 1995 under the Euratom 3rd FWP, EUR 16695 EN, 1996. This report covered phenomena, experimental programmes, material data, main modelling codes, code assessments, identification of modelling needs, and conclusions/recommendations including the needs for further research. Such knowledge is relevant to such safety issues as in-vessel retention of the core, recovery of the core by water reflood, hydrogen generation and fission product release.
The aim here is to update these reports considering relevant work done in the intervening 20 years, producing a new detailed SOAR and publishing the results in the open literature.
DESCRIPTION OF WORK
- The technical issues are those covered in the previous CSNI SOAR and its EC update, and in the OECD/CSNI Validation Matrix of 2000, with particular attention being paid to the results of Phébus FP and relevant ISTC, OECD and national projects, code benchmarks, and the concluding reports of the two SARNET EC projects, including consideration of research priorities;
- It considers the experimental database and the major severe accident analysis codes used in Europe for severe accident analysis in operating water-cooled reactors;
- It is consistent with the 2015 NUGENIA global vision roadmap;
- Therefore particular attention will be paid to in-vessel melt retention, including BWR-specific aspects (in view of Fukushima), and link with H2020 IVMR project on in-vessel melt retention, a high priority research issue within NUGENIA/SARNET Technical Area N°2 (severe accidents);
- Thermophysical databases will be specifically treated;
- Other features treated for the first time are CANDU-specific matters, VVER-specific matters, and the important industry severe accident analysis code MAAP, used widely for PSA level 2 studies.
Particular attention being paid to the results of Phébus FP and relevant ISTC (Russian collaboration), OECD and national projects, code benchmarks, and the concluding reports of the two SARNET EC projects, including consideration of research priorities.
MAIN RESULTS / HIGHLIGHTS
The chapter on the need for further research on in-vessel core degradation.
1 July 2016 – 30 June 2018
IRSN / EDF / GRS / IKE Stuttgart / JRC/ITU / KIT / CEA
KTH / MTA EK / NUBIKI / PSI
Technical Project Leader: Tim Haste (IRSN) firstname.lastname@example.org