Increased interest in development of nuclear power engineering, first of all in non-nuclear countries, puts an emphasis on the designing of small and medium nuclear power plants and determines the growth in nuclear technology export from countries with advanced nuclear industries. It accentuates the issue of reduction of the nuclear material proliferation risk, which was repeatedly raised on the national an international levels (materials of INPRO, GNEP, IAEA).

The paper presents a description of benchmark cases, achieved results, analysis of possible reasons of differences of calculation results obtained by various neutronic codes. The comparative analysis is presented showing the benchmark–results obtained with reference and design codes by Russian specialists (WIMS-D, JAR-HTGR, UNK, MCU, MCNP5-MONTEBURNS1.0-ORIGEN2.0), by French specialists (APOLLO2, TRIPOLI4 codes), and by Korean specialists (HELIOS, MASTER, MCNP5 codes). The analysis of possible reasons for deviations was carried out, which was aimed at the decrease of uncertainties in calculated characteristics. This additional investigation was conducted with the use of 2D models of a fuel assembly cell and a reactor plane section.