Development and verification of the TR-BN software for substantiation of normal operation modes of BN reactors

Substantiation of design parameters of sodium-cooled fast reactor facilities (BN RF) in normal operation modes represent an important task solution of which is necessary for determining safe and optimal reactor operation conditions. Software tools existing for the purpose allow implementing calculation analysis of separate types of equipment (for example, steam generators) or of circulation loops (secondary and tertiary cooling loops). The TR-BN software developed for the purpose of complex analysis of thermal hydraulic parameters is intended for determination of the main design characteristics (temperature, pressure) for all heat removing loops (including the primary cooling circuit) and for optimization of algorithms of BN RF operation in normal operation modes on different power levels.Brief description of the software and of the calculation methodology, as well as of possible calculation options depending on the steam generator design is given. Verification and cross-verification of the TR-BN software were implemented by way of comparison of calculated results with operational characteristics of BN-600 reactor facility and with results of calculation of BN-800 steam generator obtained using the Korsar/GP computer code. Analysis of the obtained results demonstrated satisfactory agreement with maximum discrepancy for temperature not exceeding 7.5% for sodium and 14.2% for steam. Standard uncertainties of parameters calculated using the TR-BN software and characterizing the accuracy of the performed calculations were determined. Possibility was demonstrated to use the software in the normal operation modes in the substantiation of safety of the BN RF.