Mechanics & Industry
Volume 15, Number 4, 2014
|Page(s)||301 - 305|
|Published online||20 June 2014|
CAST3M modelling of a spent fuel assembly bending during a handling accident Rod failure risk evaluation from the experimental results of spent fuel rod bending test
CEA, DEN, DANS, DM2S, SEMT, LM2S, 91191
2 CEA, DEN, DANS, DM2S, SEMT, DYN, 91191 Gif-sur-Yvette, France
3 CEA, DEN, DMN, SEMI, DIR, 91191 Gif-sur-Yvette, France
4 CEA, DEN, DMN, SEMI, LCMI, 91191 Gif-sur-Yvette, France
5 CEA, DEN, DANS, DM2S, SEMT, EMSI, 91191 Gif-sur-Yvette, France
6 EDF, SEPTEN, 69628 Villeurbanne, France
7 EDF, Renardières, 77818 Moret-sur-Loing, France
a Corresponding author: firstname.lastname@example.org
Received: 17 June 2013
Accepted: 25 April 2014
The fuel handling operating rules exclude any accidental risk. However in the framework of the PRECCI R&D project, the bending of a spent fuel assembly resulting from its locking during a translation displacement is taken into account. This enabled us to develop an approach based on experiments and calculations that allows us to simulate the behaviour of an assembly under such loading. This study was carried out in CEA laboratories with the funding and the technical support of EDF. A three points bending test on a spent fuel rod segment was performed at the Laboratory for Mechanical Behaviour of Irradiated Materials (LCMI). From the experimental strength-displacement curve, a maximum failure strain, a maximum failure curvature and an equivalent constitutive equation were determined. CAST3M modelling of the fuel rod taking into account the elasto-plastic behaviour of the clad and the cracking of the UO2 fuel pellets was verified by the experimental results. Consequently, the identification of the respective contributions of the clad and of the pellets to the rod global behaviour was made possible. A two dimensional assembly with beam elements was modelled with CAST3M. The properties of the beams modelling the different parts of the assembly (top and bottom nozzle, grids) were chosen and adjusted according to their materials (zirconium alloys, steel) in order to obtain stiffness, tensile and shear behaviour, sliding and holding functions close to the experimental ones. Assembly bending calculations were performed. In order to obtain a rod integrity estimator, their maximum calculated strains and curvatures as a function of the bending angles can be compared to the failure experimental ones.
Key words: Spent fuel rod / assembly bending / rod integrity / CAST3M
© AFM, EDP Sciences 2014
Current usage metrics show cumulative count of Article Views (full-text article views including HTML views, PDF and ePub downloads, according to the available data) and Abstracts Views on Vision4Press platform.
Data correspond to usage on the plateform after 2015. The current usage metrics is available 48-96 hours after online publication and is updated daily on week days.
Initial download of the metrics may take a while.