Filtered generated 761 hits.
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2013:24 Modelling of nuclear fuel cladding under loss-of-coolant accident conditions
We present a unified model for calculation of zirconium alloy fuel cladding rupture during a postulated loss-of-coolant accident in light water reactors. The model treats the Zr alloy solid-to-solid phase transformation kinetics, cladding creep deformation, oxidation and rupture as a function of temperature and time in an integrated fashion during the transient. The fuel cladding material...
Content type: Publications -
2013:01 Validation of Weld Residual Stress Modeling in the NRC International Round Robin Study
Weld residual stresses (WRS) have a large influence on the behavior of cracks growing under normal operation loads and on the leakage flow from a through-wall crack. Accurate prediction on weld residual stresses is important to make proper decisions when cracks in weld joints are detected. During the latest years, there has been a strong development in both analytical procedures to...
Content type: Publications -
2013:04 Research and Development Program in Reactor Diagnostics and Monitoring with Neutron Noise Methods, Stage 18
The program executed in Stage 18 consists of the following three parts: Application of CoreSim with a two-dimensional model of vibrating fuel assemblies, for the calculation of ex-core detector noise throughout a fuel cycle; An investigation of the neutron noise, induced by propagating perturbations, in various thermal and fast reactor systems, in two-group theory; A consistent derivation of...
Content type: Publications -
2009:16 Influence of Hardening Model on Weld Residual Stress Distribution
Weld residual stresses have a large influence on the behavior of cracks growing under normal operation loads and on the leakage-flow from a through-wall crack. Accurate prediction of these events is important in order to arrive at proper conclusions when assessing detected flaws, for inspection planning and for assessment of leak-before-break margins. Therefore, it is very important to have...
Content type: Publications -
2007:43 ProLBB - A Probabilistic Approach to LeakBefore Break Demonstration
The SKI regulation SKIFS 2004:2 allows for the use of Leak Before Break (LBB) as one way to provide assurance that adequate protection exists against the local dynamic consequences of a pipe break. The way to demonstrate that LBB prevails relies on a deterministic procedure for which a leakage crack is postulated in certain sections of the pipe based on the leak detection capability of the...
Content type: Publications -
2008:30 A model for fission gas release from mixed oxide nuclear fuel
Nuclear fuel containing mixed oxide (MOX) pellets have been used since the 1960´s. MOX fuel pellets are made from a mixture of uranium and plutonium oxide. MOX allows the large quantities of fissile isotopes produced and remaining in spent nuclear fuel from light water reactors to be recycled. Producing MOX fuel can be seen as a method to more efficiently use the natural uranium since...
Content type: Publications -
2007:23 On Safety Management, A Frame of Reference for Studies of Safety Management with Examples From Non-Nuclear Contexts of Relevance for Nuclear Safety
The authors present the theoretical framework. There they also discuss the pros of using the system perspective to build a useful frame of reference of safety management using non- nuclear organizations; this as a way to create models useful for the nuclear power industry but based on general understanding of the concept of safety management. The chosen organizations are used extensively to...
Content type: Publications -
2009:17 Effect of Welding Residual Stresses on Crack Opening Displacement and Crack-Tip Parameters
Weld residual stresses have a large influence on the behavior of cracks growing under normal operation loads and on the leakage-flow from a through-wall crack. Accurate prediction of these events is important in order to arrive at proper conclusions when assessing detected flaws, for inspection planning and for assessment of leak-before-break margins. The fracture mechanical treatment of weld...
Content type: Publications -
SSM Report 2008:01 A combined deterministic and probabilistic procedure for safety assessment of components with cracks – Handbook
SSM has supported research work for the further development of a previously developed procedure/handbook (SKI Report 99:49) for assessment of detected cracks and tolerance for defect analysis. During the operative use of the handbook it was identified needs to update the deterministic part of the procedure and to introduce a new probabilistic flaw evaluation procedure. Another identified need...
Content type: Publications -
1994:08 The content and environmentalimpact from the waste depositoryin Sillamae
The studies of the waste depository in Sillamae, Estonia, shows that the content as well as the wall material is typical tailings from chemical enrichment of uranium ore. The environmental impact from radioactive substances as well as heavy metals has been estimated. Results show the major radiological impact to the population in the Sillamae town is the exposure to radon and its daughter...
Content type: Publications