Issue 36

T. Fekete, Frattura ed Integrità Strutturale, 36 (2016) 99-111; DOI: 10.3221/IGF-ESIS.36.10

o a model designed for elastic calculations; the geometrical model is composed from two sub-models: 1. a 3D Finite Element (FE) model of a lower-cylindrical part of the vessel with the bottom; the purpose of the model was the calculation of through wall temperature, stress and strain distributions occurring during PTS transients, and provide inputs to subsequent fracture mechanics calculations. The FE mesh models the welds, and includes quadratic, iso-parametric brick-type elements with 20 nodal points, but does not model the crack in the mesh. The developed model contains 58240 elements and 247405 nodal points. The geometrical model is presented on Fig. 1.

Figure 1 : 3D Finite Element model of a lower cylindrical part, bottom and welds of a VVER-440 RPV.

2. 3D models of the main coolant pipeline nozzles  492; the purpose of the models was to calculate through wall temperature, stress and strain distributions occurring during PTS transients, and provide inputs to subsequent fracture mechanics calculations. The FE mesh includes quadratic, iso-parametric brick-type elements with 20 nodal points. The developed model contains 7320 elements and 34144 nodal points. The geometrical model is presented on Fig. 2.

Figure 2 : 3D Finite Element model of a main coolant pipeline nozzle  492.

105