快堆燃料组件少孔式管脚替代方案水力实验研究

工程中广泛应用的多孔式管脚在流动特性调节、加工精度方面存在一定缺陷。本文提出了少孔式管脚替代方案，通过水力实验，对比研究了多孔式与少孔式两类管脚的阻力系数分布、流量与压降对应关系等流动特性。结果显示：ø12.0 mm的少孔式管脚与ø6.2 mm的多孔式管脚具有几乎相同的流动特性，均满足设计需求，本文提出的少孔式管脚替代方案可行；少孔式管脚具有更高的流动特性调节效率。本文给出了管脚阻力系数与其结构尺寸间的经验关系式，可供相关实验或工程参考。

Hydraulic Experimental Investigation on Alternative Method of Few-hole Entry Tube for Fast Reactor Fuel Assembly

The multi-hole entry tube widely used in engineering has some shortcomings in adjustment of flow characteristics and processing accuracy. In this paper, an alternative method of few-hole entry tube was proposed. By hydraulic experiment, the flow characteristics of multi-hole and few-hole entry tubes, such as the distribution of resistance coefficient, the corresponding relationship between flow rate and pressure drop, were compared and studied. The results show that the flow characteristic of the few-hole entry tube with 12.0 mm in diameter is almost the same as that of the multi-hole entry tube with 6.2 mm in diameter, which all can meet the design requirements. It is verified that the alternative method of few-hole entry tube proposed in this paper is feasible. In addition, the flow characteristics can be more effectively adjusted by the few-hole entry tube. Moreover, the empirical correlation between the resistance coefficient of the entry tube and its structure parameters is formulated, which can be used in relevant experiment or engineering.