Effect of Check Valve on Consequences of Coolant Pump Rotor Seizure Accident for EPR Reactor

Counter current flow phenomenon would appear during reactor coolant pump rotor seizure accident.Present work analyzes the coolant pump rotor seizure accident for European Pressurized Reactor（EPR）.The accident safety analysis results of model with check valve and without check valve are compared.It can be found that the check valve can increase the core inlet flow rate of model about 4%.The increasing of coolant flow rate is beneficial to the reactor core cooling.Check valve can increase the minimum departure from nucleate boiling ratio（DNBR）,reduce the departure from nucleate boiling（DNB） fraction and the fuel rod cladding temperature about 14℃ during coolant pump rotor seizure accident.The analyses results show that the model with check valve can maintain the integrity of nuclear fuel rod effectively during reactor coolant pump rotor seizure accident.