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2022:09 Assessment of modelling approaches for axial gas flow inside LWR fuel rods
SSM perspective Background The fuel rod analysis program SCANAIR has been developed by IRSN (Institut de Radioprotection et de Sûreté Nucléaire) for analysis of reactivity initiated accidents (RIA) in light water reactors. The Swedish Radiation Safety Authority (SSM) has access to SCANAIR in exchange for annual contributions for its further development. The development...
Content type: Publications -
2022:08 Geophysical surveys on sub marine land- and rock slides and on alpine glaciers
SSM perspective Background The future climate evolution and the impact it might have on a repository for radioactive waste is important when assessing the long-term safety. In a project funded by SSM (Holmlund et al. 2016), bathymetric data from the Southern Quark area between Sweden and Åland, provided by the Swedish Maritime Administration, were analysed, as well as terrestrial data from...
Content type: Publications -
2022:04 Warm Pre-Stressing mechanisms
SSM perspective Background Swedish nuclear power plants (NPP) were originally designed and analyzed with an assumed operating period of approximately 40 years. As Swedish NPPs reach their original technical design life the safety of the additional operating time has to be verified. With increased operating time, the shift in the fracture toughness curve of the reactor pressure vessel (RPV)...
Content type: Publications -
2022:03 Effect of Neutron Irradiation on the Oxidation and Corrosion of Austenitic Stainless Steels
SSM perspective Background Reactor pressure vessel internal components of austenitic stainless steel located close to the core are subject to a high neutron flux. Irradiation by fast neutrons induces changes in the material that affect microstructure, mechanical properties and microchemistry. These changes eventually lead to an increased susceptibility to irradiation assisted stress corrosion...
Content type: Publications -
2021:28 Analysis of Radon Levels in Swedish Dwellings and Workplaces
SSM perspective Background Exposure to radon is considered the second most important cause of lung cancer next to smoking and is estimated to account for about 500 lung cancer cases per year in Sweden. For this reason, it is important to lower radon concentrations in indoor air, particularly where levels exceed the reference level 200 Bq/m³. In order to be able to update calculations on number...
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2021:21 Region-specific radioecological evaluation of accidental releases of radionuclides from ESS
SSM perspective Background To strengthen the material science research in Europe, the European Spallation Source (ESS) is being built in Lund in the southern part of Sweden. In the spallation process, neutrons are generated when the accelerated protons hit the tungsten target. In addition, a broad range of radioactive by-products are produced that differs from the fission products produced...
Content type: Publications -
2021:20 Effects of additives on UO2 fuel behavior: expanded edition
SSM perspective Background The Swedish Radiation Safety Authority (SSM) follows the development of nuclear fuel closely. Fuel with additives like chromia and gadolinia is used in Swedish reactors and fuel with even better thermal and mechanical properties is under development. This project is an in-depth study of data and models regarding the impact of additives on the properties of uranium...
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2021:19 Importance Sampling Time-Domain Random Walk (ISTIDRAW) Version 1.0 User Guide A Code for Radionuclide Transport in Pathway Networks
SSM perspective Background To support regulatory review of post-closure safety assessments of geological disposal systems it is of importance to possess regulatory independent modelling capacity. Typically, SSM’s independent modelling includes performing simple scoping calculations, utilizing the implementer’s own models with other equation solvers, or defining alternative conceptual models.
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2021:14 Reliability, Feasibility and Significance of Measurements of Conductivity and Transmissivity of the Rock Mass for the Understanding of the Evolution of a Repository of Radioactive Waste
SSM perspective Background The conducted research was part of the international research project DECOVALEX 2019 (DEvelopment of COupled models and their VALidation against EXperiments). DECOVALEX 2019 consisted of seven different research projects called Task A to G. SSM were involved in Task G, which were composed of three different teams from Technical University of Liberec (TUL),...
Content type: Publications -
2021:13 SSM’s external experts’ review of SKB’s safety evaluation SE-SFL
SSM perspective Background In Sweden long-lived low- and intermediate level radioactive waste is planned to be disposed in a repository (SFL) in the Swedish crystalline rock at a depth around 500 m. The waste contains mainly the long-lived wastes from the operation and decommissioning of the Swedish nuclear reactor plants, as well as the long-lived wastes from early research in the Swedish...
Content type: Publications