An Analysis of Criticality Achievement Process

29th Symposium of AER on VVER Reactor Physics and Reactor Safety (2019, Energoland, Mochovce NPP, Slovakia)
[3] fuel management issues


J.Bajgl, M.Bárta


The implementation of the Low Leakage Loading Pattern (L3P) in Dukovany NPP (VVER-440) led to high differences between expected undercriticality during criticality achievement process and measured one. There was formulated a new approach to the undercriticality inspection during criticality achievement process in previous paper in 2014. This method has been used during start-up in Dukovany NPP since 2012.
Non-uniform distributions of spontaneous fission sources in different loading patterns are described in this paper. There is presented and discussed a new correction function formulation used during the criticality achievement process assessment.