Comparative Analysis of Thermal Hydraulic Parameters of AP-1000 and VVER-1200 Nuclear Reactor for Turbine Trip Concurrent with Anticipated Transient Without SCRAM (ATWS)

Generation III+ type nuclear reactors have highly reliable active and passive safety systems with some inherent safety characteristics for attaining proper operating conditions, preventing any chance of accidents, or minimizing after-effects if any accident occurs to ensure that workers, the public and the environment are safe from undue radiation hazards. In this paper, Simulations of turbine trip along with Anticipated Transient Without Scram (ATWS) of AP-1000 and VVER-1200 reactors are analyzed to clarify their characteristics and compare their thermal-hydraulics parameters. To simulate the transient responses for the combination of malfunctions Personal Computer Transient Analyzer (PCTRAN) has been used. The results are showing all important parameters including pressure, temperature and void fraction of the Reactor Coolant System (RCS), water level and pressure of the pressurizer, Departure from Nucleate Boiling Ratio (DNBR), are found to be within the safety limit for both AP-1000 and VVER-1200 reactor. Thus, the results are in good agreement with the Primary Safety Analysis Safety report (PSAR) for both reactors.