Main modelling features of the ASTEC V2.1 major version. (July 2016)

• Record Type: Journal Article
• Authors: Chatelard, P.; Belon, S.; Bosland, L.; Carénini, L.; Coindreau, O.; Cousin, F.; Marchetto, C.; Nowack, H.; Piar, L.; Chailan, L.
• Is Part Of: Annals of nuclear energy. Volume 93(2016:Jul.)
• Page Start: 83
• Page End: 93
• Publication Date: 2016-07
• Subjects: ASTEC Accident Source Term Evaluation Code -- BARC Bhabha Atomic Research Centre, India -- BIP Behaviour of Iodine Project -- BWR Boiling Water Reactor -- CATHARE Code Avancé de THermohydraulique pour les Accidents sur les Réacteurs à Eau -- CCI corium concrete interaction -- CEA Commissariat à l'Énergie Atomique et aux Énergies Alternatives, France -- CESAM Code for European Severe Accident Management -- CHIP CHemistry of Iodine in the Primary circuit -- CORDEB CORium/DEBris behaviour in the lower head -- CSNI Committee on Safety of Nuclear Installations -- CT calandria tube -- EC European Commission -- EPICUR Experimental Programme for Iodine Chemistry Under Radiation -- FP fission product -- FP7 7th Framework Programme -- GRS Gesellschaft für Anlagen- und Reaktorsicherheit gGmbH -- IRSN Institut de Radioprotection et de Sûreté Nucléaire -- ISTP International Source Term Programme -- IVMR in-vessel melt retention -- JASMIN Joint Advanced Severe accident Modelling and INtegration for sodium-cooled fast neutron reactors -- KIT Karlsruhe Institute of Technology -- LCDA Limited Core Damage Accident -- LOCA loss of coolant accident -- LWR Light Water Reactor -- MCCI molten core concrete interaction -- MOZART Mesure de l'Oxydation du Zirconium par l'AiR en Température -- NITI Nauchno-Issledovatel'skii Tekhnologicheskii Institute, Russia -- NPP nuclear power plant -- OECD Organisation for Economic Cooperation and Development -- PAR passive autocatalytic recombiner -- PASSAM Passive and Active Systems on Severe Accident source term Mitigation -- PEARL Programme Expérimental Analytique sur le Renoyage des Lits de débris -- PHWR Pressurised Heavy Water Reactor -- PRELUDE Préliminaire sur le Renoyage ExpérimentaL d'Un lit de DEbris -- PSA2 level 2 Probabilistic Safety Assessment -- PT pressure tube -- PWR Pressurised Water Reactor -- RCS reactor coolant system -- SA severe accident -- SAFEST Severe Accident Facilities for European Safety Targets -- SAM Severe Accident Management -- SARNET Severe Accident Research NETwork -- SBLOCA small break LOCA -- SCDA Severe Core Damage Accident -- SM structural materials -- SSWICS Small Scale Water Ingression and Crust Strength -- STEM Experimental programme for study of Source Term and Mitigation -- ST source term -- SUNSET Statistic UNcertainty and Sensitivity Evaluation Tool -- THAI Thermal Hydraulics And Iodine; ASTEC -- Severe accidents -- Code simulation; Nuclear energy -- Periodicals; Nuclear engineering -- Periodicals; 621.4805
• DOI: 10.1016/j.anucene.2015.12.026
• Languages: English
• ISSNs: 0306-4549

Abstract

Highlights: Recent modelling improvements of the ASTEC European severe accident code are outlined. Key new physical models now available in the ASTEC V2.1 major version are described. ASTEC progress towards a multi-design reactor code is illustrated for BWR and PHWR. ASTEC strong link with the on-going EC CESAM FP7 project is emphasized. Main remaining modelling issues (on which IRSN efforts are now directing) are given. Abstract: A new major version of the European severe accident integral code ASTEC, developed by IRSN with some GRS support, was delivered in November 2015 to the ASTEC worldwide community. Main modelling features of this V2.1 version are summarised in this paper. In particular, the in-vessel coupling technique between the reactor coolant system thermal-hydraulics module and the core degradation module has been strongly re-engineered to remove some well-known weaknesses of the former V2.0 series. The V2.1 version also includes new core degradation models specifically addressing BWR and PHWR reactor types, as well as several other physical modelling improvements, notably on reflooding of severely damaged cores, Zircaloy oxidation under air atmosphere, corium coolability during corium concrete interaction and source term evaluation. Moreover, this V2.1 version constitutes the back-bone of the CESAM FP7 project, which final objective is to further improve ASTEC for use in Severe Accident Management analysis of the Gen.II–III nuclear power plants presently under operation or foreseen in near future in Europe. As part of this European project, IRSN efforts to continuously improve both code numerical robustness and computing performances at plant scale as well as users' tools are being intensified. Besides, ASTEC will continue capitalising the whole knowledge on severe accidents phenomenology by progressively keeping physical models at the state of the art through a regular feed-back from the interpretation of the current and future experimental programs performed in the international frame.