Abstract
RETRAN-3D,a computer program for transient thermal-hydraulic analysis of complex fluid flow system,has been applied generally to nuclear engineering.The thesis’s content includes the input data calculation and the process of initialization procedure forLungmen RETRAN system model, because that when we do some startup tests or safety analysis on different initial conditions(fuel cycle, power, core flow, pressure etc…), we should guarantee the initial condition’s stability by modifying the base deck using the initialization procedure. Analysis model has been developed for the first advanced boiling water reactor (ABWR) in Taiwan, Lungmen NPP. Especially, Lungmen ABWR has ten reactor internal pumps.Theresearch investigates the plant responses to trips of one and three RIPs(Startup test) and all RIPs(Safety analysis) determines whether the test resultare met with Startup test report and FSAR in these transient simulations.In the event of the all RIPs trip, changing the initial conditions (power and core flow) by previous procedure and checking if scram or not can be done in the set point analysis. The scram signal called rapid core flow coastdown is about the core flow’s change rate. The Core flow measurements have the delayed time so that the delayed time could affect the scram result. At 100% power and core flow initial condition, to do the sensitivity study, tuning this time constant can result the scram or not with different number of RIPs trip.