VVER-440 Reactor Vessel Exposure Monitoring in the Czech Republic

Abstract

A short review of the current reactor pressure vessel fast neutron fluence monitoring and evaluation methodology is presented. The reactor pressure vessel exposure must be evaluated for every fuel cycle combining calculations, surveillance monitors, exvessel (cavity) monitors and other experimental results. The series of WER-440 mock-up experiments were carried out in the LR-0 experimental reactor in the Nuclear Research Institute. The results were revised and the authorized data files were completed. A recommended practice for the use of mock-up results in fluence monitoring system was prepared. A database consisting of the surveillance and exvessel fast monitor data and the mock-up results is used to increase the reliability of the reactor pressure vessel exposure evaluation.