+78136960367 korsar@niti.ru

The KORSAR code is intended for numerically simulating the VVER reactor dynamics during normal operation, operational failures of the primary and secondary system equipment, and design basis and beyond design basis accidents. It can also be used to model thermal-hydraulics of test facilities with water-cooled reactors.  The KORSAR code provides for coupled numerical modeling of transient neutronic and thermal-hydraulic processes in VVER reactors under normal and abnormal operating conditions with/without consideration of noncondensable gas behavior in the coolant water.

In particular, KORSAR can be used for

  • numerical safety assessment of operating VVER NPPs including those under modernization processes;
  • calculation of VVER dynamics at the basic and detailed design stages;
  • deterministic calculations of transient and accident conditions in VVERs (as part of PSA);
  • numerical analysis of VVER design basis conditions in support of accident management procedure development;
  • testing of software being developed for VVER simulators, training simulators, and simulator systems;
  • modeling of thermal-hydraulic processes in water-cooled prototype reactor plants and test facilities.
    • Application limitations:
  • thermal-hydraulic processes in the VVER secondary system are only simulated for the regions upstream of the turbine stop and control valves;
  • analysis of beyond design basis accidents does not apply to core melt scenarios with deformation of the flow geometry;
  • initial dynamic conditions are limited to normal operational states at nominal and intermediate power levels and reactor shutdown.
    • Parameters:
  • coolant – mixture of water (with dissolved boron and noncondensables) and vapor-gas phase (with an arbitrary proportion of vapor and noncondensables);
  • boron concentration in the liquid phase – from 0 to the saturation point at a given temperature;
  • noncondensable gases – hydrogen (Н2), oxygen (О2), nitrogen (N2), helium (Не);
  • pressure – from 0.1 to 22.0 MPa;
  • liquid phase temperature – from 20°С to 374.12°С;
  • vapor-gas phase temperature – from 20°С to 1200°С;
  • temperature of structural materials – below the melting point;
  • fuel:
  • uranium-based and regenerated uranium-based oxide fuel;
  • uranium-based fuel with gadolinium burnable poison;
  • control rods:
  • control rod cluster;
  • emergency control rod assembly (in VVER-440 design);
  • control rod materials – boron, dysprosium, hafnium;
  • burnable poison rod materials – boron and gadolinium;
  • nuclear chain reacting medium:
  • water to uranium ratio – from 1.5 to 2.5;
  • fuel enrichment level – up to 6%;
  • Gd2O3 content in gadolinium fuel rods – up to 8%;
  • fuel burnup – up to 70 MV×day/kg;
  • boron concentration – from 0 to 16 g/kg;
  • coolant density in the core – from 200 to 1000 kg/m3.