Modeling of dynamic processes in nuclear reactors is carried out, mainly, on the basis of the multigroup diffusion approximation for the neutron flux. The basic model includes a multidimensional set of coupled parabolic equations and ordinary differential equations. Dynamic processes are modeled by a successive change of the reactor states, which are characterized by given coefficients of the e...

The safety performance of nuclear power plants (NPPs) is a very important factor in evaluating energy sustainability. Safety analysis passive and active systems have positive influence on reactor transient mitigation. One the common transients primary coolant leg rupture. This study focused guillotine large break loss (LB-LOCA) one vessels, which cold rupture occurred, after establishment stead...

The procedures of validation and cross-verification the newly developed computational code ROK/B are described. main problem solved using is substantiation by calculation coolant density in spent fuel pool (SFP) temperature regime assemblies during a protracted shutdown cooling systems (break supply water). In addition to above, it possible use carry out an accident with discharge from SFP simu...

In this paper the phase formation and mechanical properties of VVER-type reactor pressure vessel (RPV) steels with various Ni (1.57–5.95 wt.%) Mn (0.03–0.76 content after neutron irradiation up to fluences in range (53–120) × 1022 n/m2 at 400 °C were studied. The possibility carbonitride under these conditions is shown. case sufficient (>1.5 (>0.3 Ni-Si-Mn precipitates observed. Their che...