Development of reactor internals for next generation BWR

During development of the reactor internals for the next generation BWRs, an improved separator and dryer system was studied. As the results of the air-water experiments, the steam dryer unit of the vane angle 90 degree-2 wave has 11% carry over compared to the present 120 degree-4 wave unit with almost the same pressure drop. By using the 90 degree-2 wave steam dryer unit which is 0.8 m shorter than the present one in combination with the steam separator which is 0.8 m taller and has 30 degree swirler angle, high droplet removal efficiency and a low pressure drop system can be realized. This improved steam dryer and separator system saves pump power and increases the operating water level range. In addition, it has the possibility of reducing the carry over of radioactivity to the turbine system. These merits result in the easy operation and lower cost for the next generation BWRs