Identification and categorisation of safety issues for ESNII reactor concepts. Part I: Common phenomena related to materials

International audience; With the aim to develop a joint proposal for a harmonised European methodology for safety assessment of advanced reactors with fast neutron spectrum, SARGEN-IV (Safety Assessment for Reactors of Gen IV) Euratom coordination action project gathered together twenty-two partners' safety experts from twelve EU Member States. The group consisted of eight European Technical Safety Organisations involved in the European Technical Safety Organisation Network (ETSON), European Commission's Joint Research Centre (JRC), system designers, industrial vendors as well as research and development (RandD) organisations. To support the methodology development, key safety features of four fast neutron spectrum reactor concepts considered in Deployment Strategy of the Sustainable Nuclear Energy Technology Platform (SNETP) were reviewed. In particular, outcomes from running European Sustainable Nuclear Industrial Initiative (ESNII) system projects and related Euratom collaborative projects for Sodium-cooled Fast Reactors, Lead-cooled Fast Reactors, Gas-cooled Fast Reactors, and the lead-bismuth eutectic cooled Fast Spectrum Transmutation Experimental Facility were gathered and critically assessed. To allow a consistent build-up of safety architecture for the ESNII reactor concepts, the safety issues were further categorised to identify common phenomena related to materials. Outcomes of the present work also provided guidance for the identification and prioritisation of further RandD needs respective to the identified safety issues. © 2015 The Authors. Published by Elsevier Ltd. This is an open access article under the CC BY-NC-NDlicense

Spallation reactions. A successful interplay between modeling and applications

The spallation reactions are a type of nuclear reaction which occur in space by interaction of the cosmic rays with interstellar bodies. The first spallation reactions induced with an accelerator took place in 1947 at the Berkeley cyclotron (University of California) with 200 MeV deuterons and 400 MeV alpha beams. They highlighted the multiple emission of neutrons and charged particles and the production of a large number of residual nuclei far different from the target nuclei. The same year R. Serber describes the reaction in two steps: a first and fast one with high-energy particle emission leading to an excited remnant nucleus, and a second one, much slower, the de-excitation of the remnant. In 2010 IAEA organized a worskhop to present the results of the most widely used spallation codes within a benchmark of spallation models. If one of the goals was to understand the deficiencies, if any, in each code, one remarkable outcome points out the overall high-quality level of some models and so the great improvements achieved since Serber. Particle transport codes can then rely on such spallation models to treat the reactions between a light particle and an atomic nucleus with energies spanning from few tens of MeV up to some GeV. An overview of the spallation reactions modeling is presented in order to point out the incomparable contribution of models based on basic physics to numerous applications where such reactions occur. Validations or benchmarks, which are necessary steps in the improvement process, are also addressed, as well as the potential future domains of development. Spallation reactions modeling is a representative case of continuous studies aiming at understanding a reaction mechanism and which end up in a powerful tool.Comment: 59 pages, 54 figures, Revie

Production of radiotoxic isotopes in LBE spallation targets: recent extensions of the INCL4 model and experimental validation

Recent extensions of the Liège intranuclear cascade (INCL) model concerning the mean field of the baryons, the pion sector and a refinement of the Pauli blocking for the first collision have led to an improved description of the production of radiotoxic isotopes induced by protons in thin targets. In this paper we have investigated the production of some highly radiotoxic isotopes in thick target. With this aim, the INCL4 model implemented in the MCNPX code has been modified. We have adapted the ALEPH code to perform the evolution of a spallation target. The standard INCL4 model and our modified INCL4 version were compared to the experimental results measured at PSI with a stack of lead and bismuth disks. The same conclusion drawn from thin target results is also obtained. In thin and in thick spallation targets, the production of the highly radiotoxic 209Po and 208Po isotopes is reduced. In thick targets, the production of 210Po and of 210mBi are feeded by (n,γ) reactions and are not affected by the recent extensions

Influence of nucleon and pion mean fields of the description of spallation reactions

Intranuclear cascade plus evaporation models are able to describe spallation reactions using very few input, among which a mean field for nucleons and for pions, generally under the form of crude potential wells. The influence of this ingredient, especially of the isospin and the energy-dependence of the nucleon mean field is investigated. The influence of the presence of a pion mean field is also studied

Intra-nuclear cascade models at low energy?

Basic assumptions of the INC models are ``revisited'' in order to examine their applicability limits at low energies. Details of implementations of INC important at low energies are discussed

Improvements of INCL4 in view of more reliable predictions for RIB facilities

Some improvements of the Intra-Nuclear Cascade code INCL4 for low energy projectiles are presented and discussed

The INCL Model for Spallation Reactions Below 10 GeV

The Liège intranuclear cascade (INCL) model is shortly presented. The predictive power of its standard version concerning the description of nucleon-induced spallation reactions in the 200 MeV to ~2 GeV range of incident energy is indicated. Current improvements of the model, in particular its extension to higher energies, are emphasized. The capabilities of the model for possible applications in astrophysics, space research and protontherapy are pointed out

Identification and Categorisation of Safety Issues for ESNII Reactor Concepts. Part I: Common phenomena related to materials

With the aim to develop a joint proposal for a harmonised European methodology for safety assessment of advanced reactors with fast neutron spectrum, SARGEN_IV (Safety Assessment for Reactors of Gen IV) Euratom coordination action project gathered together 22 partners’ safety experts from 12 EU Member States. The group consisted of eight European Technical Safety Organisations involved in the European Technical Safety Organisation Network (ETSON), European Commission’s Joint Research Centre (JRC), system designers, industrial vendors as well as research & development (R&D) organisations. To support the methodology development, key safety features of four fast neutron spectrum reactor concepts considered in Deployment Strategy of the Sustainable Nuclear Energy Technology Platform (SNETP) were reviewed. In particular, outcomes from running European Sustainable Nuclear Industrial Initiative (ESNII) system projects and related Euratom collaborative projects for Sodium-cooled Fast Reactors, Lead-cooled Fact Reactors, Gas-cooled Fast Reactors, and the lead-bismuth eutectic cooled Fast Spectrum Transmutation Experimental Facility were gathered and critically assessed. To allow a consistent build-up of safety architecture for ESNII reactor concepts, the safety issues were further categorised to identify common phenomena related to materials. Outcomes of the present work also provided guidance for identification and prioritisation of further R&D needs respective to the identified safety issues.JRC.F.5-Nuclear Reactor Safety Assessmen

Identification and categorisation of safety issues for ESNII reactor concepts. Part I: Common phenomena related to materials

International audienceWith the aim to develop a joint proposal for a harmonised European methodology for safety assessment of advanced reactors with fast neutron spectrum, SARGEN-IV (Safety Assessment for Reactors of Gen IV) Euratom coordination action project gathered together twenty-two partners' safety experts from twelve EU Member States. The group consisted of eight European Technical Safety Organisations involved in the European Technical Safety Organisation Network (ETSON), European Commission's Joint Research Centre (JRC), system designers, industrial vendors as well as research and development (RandD) organisations. To support the methodology development, key safety features of four fast neutron spectrum reactor concepts considered in Deployment Strategy of the Sustainable Nuclear Energy Technology Platform (SNETP) were reviewed. In particular, outcomes from running European Sustainable Nuclear Industrial Initiative (ESNII) system projects and related Euratom collaborative projects for Sodium-cooled Fast Reactors, Lead-cooled Fast Reactors, Gas-cooled Fast Reactors, and the lead-bismuth eutectic cooled Fast Spectrum Transmutation Experimental Facility were gathered and critically assessed. To allow a consistent build-up of safety architecture for the ESNII reactor concepts, the safety issues were further categorised to identify common phenomena related to materials. Outcomes of the present work also provided guidance for the identification and prioritisation of further RandD needs respective to the identified safety issues. © 2015 The Authors. Published by Elsevier Ltd. This is an open access article under the CC BY-NC-NDlicense