几何结构对快堆控制棒组件管脚流动特性的影响

控制棒组件是快堆的重要安全构件，其管脚几何结构对于流动特性具有显著影响。通过水力实验研究了板式节流件管脚的流动特性，并对流体-结构耦合数值模拟方法进行了验证。结果显示：减小节流板厚度、增加连杆直径均可提高管脚节流能力；无量纲厚径比Ha=0.5、连杆直径20 mm的板式节流件管脚具有最优的流动特性。针对板式节流件管脚在实验中存在的缺陷，提出了孔板节流件作为替代方案，经验证，两类管脚速度、压力分布基本一致，该替代方案可行。

Geometrical Structure Effect on Entry-tube Flow Characteristic of Fast Reactor Control Assembly

The control assembly is an important safety component of sodium-cooled fast reactor. The entry-tube geometrical structure has a significant effect on flow characteristics. The flow characteristics of plate-throttle entry-tube were investigated by hydraulic experiment, and the fluid-structure coupling numerical simulation was verified by experiment data. The results show that reducing the thickness of throttle plate and increasing the diameter of connecting rod can effectively improve the entry-tube throttling capacity. Considering the limitation of flow velocity, the dimensionless thickness-diameter ratio of 0.5 and connecting rod diameter of 20 mm are regarded as the optimum structure parameters of entry-tube. Due to the shortage of plate-throttle entry-tube in experiment, an alternative project of square-groove entry-tube was proposed. It is verified that this project is feasible with the similar flow velocity and pressure distribution in two types of entry-tubes.