This article regards U-bend tube natural-circuit steam generator of Daya Bay Nuclear Power Station as the research target. Drift-flux dynamic model is established for the engineering application according to the characteristics of rising channel boiling section of steam generator. Based on the verification accuracy of steady state characteristic and the key parameters involved in drift-flux theory

the dynamic characteristics of steam generator are simulated and analyzed. The results suggest that the drift-flux theory can be used to predict and reflect the flow and heat transfer characteristics of two-phase flow in the steam generator. With the add of the disturbance

all parameters of steam generator show a reasonable variable trend. And the “false water level” phenomenon is accurately simulated. Meanwhile

the response speed and degree of the water level to disturbance is greater as the load increases.