Determination of the Fast Neutron Fluence on a VVER-1200 Vessel Using a Computational Model Including the Monte Carlo Method

摘要

The possibility of using the Monte Carlo method for high-speed calculations of the fast-neutron fluence on a VVER-1200 vessel during some time interval is substantiated. In the model developed, the flow attenuation behind the core is described using the MCU-PD code in a computational regime at low power with an external source set alternately in the FA at the periphery of the core. The distribution of a time-varying source of fast neutron over the core is determined, in the diffusion approximation by means of the DYN3D engineering code, for actual reactor operation. The source irregularity along the FA profile is described in the x and y directions in the P1 approximation.