Owing to some backward objective conditions such as experimental facilities and laboratory space, flow excursion experiment has not been activated temporarily.

The experimental results show that in the process of flow excursion the mass flow rate and the inlet temperature decreases, while the exit temperature increases smoothly.

Based on homogeneous model and with the application of nonlinear bifurcation theory, this paper presents prediction of static bifurcation (flow excursion) diagram of two-phase natural circulation.