Calculation Modeling of Detector Activity in the VVER/Pressurized Water Reactor Vessel Surveillance

Calculation modeling of detector activity in a VVER/pressurized water reactor pressure vessel surveillance program, necessary for neutron fluence assessments, is developed. The detector activity for certain detectors could be obtained by solving the neutron transport equation by the appropriate activity source taking into consideration the time-dependent local power distribution. The presented results demonstrate the importance of accounting for local power variations.