Simulation analysis of inlet flow field for air flow path of Passive Containment Cooling System

For the purpose of simulating annulus of Passive Containment Cooling System (PCCS) of AP type nuclear power plant, the flow field simulated by the similar structure of test facility (sub-scaled) should be similar with the actual PCS. Compared with the actual PCS, the downward air flow path of annulus usually isn't implemented in the test facility. The flow field near the entrance of upward air flow path for actual PCS and sub-scaled test facility has been analyzed, in order to optimize the design of this structure designed in the test facility. The result shows the effect of flow deflector of upward air flow path entrance is obviously well. The flow field distribution of upward air flow path entrance is very uniform. By the simulating result, the entrance flow field of rising segment is uneven distribution, due to the flow reversal. The optimized result suggests that the deflector angle of 30° makes the entrance flow field of test and the actual PCS in good agreement, and suitable for test measurement. (author)