Study of neutron-physical characteristics of VVER-1200 considering feedbacks using MCU Monte Carlo code

Abstract The purpose of the work is to calculate VVER-1200 neutron-physical characteristics that are important for safety using MCU Monte Carlo code for an independent verification of the accuracy of design calculations of the first fuel cycle. The calculations were carried out before the startup of the first VVER-1200 power unit. A full-scale computer model of VVER-1200 was developed using the design documentation of the fuel assemblies and the reactor facility. Special attention was given to the accurate specification of the geometry and material description of the core and its immediate environment. The full-scale VVER-1200 model allows performing Monte Carlo calculation of some safety-relevant characteristics for which it is impossible or extremely difficult to carry out full-scale reactor experiments. In total, more than 110 different states were calculated; five states were calculated taking feedbacks into account. For all calculations, the neutron-physical characteristics obtained by means of the M...