Sub-channel analysis of fuel assemblies for innovative reactor design using the MATADOR software

The MATADOR software designed for subchannel thermohydraulic calculations of fuel assemblies with different coolants is being developed at OKB Gidropress JSC. Validation of the program with experimental data on key thermohydraulic parameters in the reactor core is of paramount importance, as it confirms the reliability of the modeling of physical processes and phenomena. The article presents the results of the validation and verification of the MATADOR subchannel program based on a series of experiments with supercritical water cooling of rod bundles conducted in China and at the NACIE-UP test facility in Italy, which has a 19-rod assembly cooled with lead-bismuth coolant. The modeling of rod bundles with wire wrapped spacers was performed using a geometric model. Analysis of the computational studies confirmed the ability of the software to reproduce measurements with acceptable accuracy for engineering practice.