Full-scale VVER-1000 model for Monte Carlo calculation of core neutron characteristics. MCU-PD and BIPR-7A results comparison

Application of a Monte Carlo method for simulating of neutron transport in nuclear reactors has more than fifty years of history. Fast progress of computer power and development of more and more perfect algorithms, codes and nuclear data bases allow solving more challenging problems, including three-dimensional calculations of full-scale reactor cores. In a process of verification of MCU-PD code full-scale three-dimensional model of first unit of the Volgodonsk nuclear power plant has been developed. Some critical states were calculated using that model. Those are states at hot zero power level achieved during physical start-up. Power distribution in fuel assemblies throughout core and power distribution throughout fuel assembly height were calculated by MCU-PD and BIPR-7A codes. Concise description of full-scale model developed, annotation of algorithms and methods for the both codes and their results comparison between themselves and with experimental data are presented. (authors)