Abstract After a LOCA, debris enters the fuel assemblies through the sump strainers of the containment, increasing the pressure drop of the fuel assemblies. Experimental study of the effects of debris passing through the strainers and settling in the reactor core within the fuel elements on the core cooling is crucial. The distribution, attachment and blockage of debris in a fuel assembly are studied by the experiment. The results show that the pressure drop is smaller than the driving head available for core cooling under a simulated cold leg break. Experiments on the AFA2G fuel assembly show that the pressure drop caused by the simultaneous introduction of three types debris into the fuel assembly is remarkable at the same flow rate and debris mass. However, the debris introduced to the fuel assembly in the order of particle debris, fiber de bris, and chemical debris can result in a lower pressure drop.

中文翻译：

---

碎片组合对燃料组件流阻的影响

摘要 发生LOCA后，碎片通过安全壳的油池过滤器进入燃料组件，增加了燃料组件的压降。碎屑通过过滤器并在反应堆堆芯内的燃料元件中沉淀对堆芯冷却的影响的实验研究是至关重要的。通过实验研究了燃料组件中碎片的分布、附着和堵塞。结果表明，在模拟冷断腿情况下，压降小于可用于堆芯冷却的驱动头。在 AFA2G 燃料组件上的实验表明，在相同的流速和碎片质量下，由三种类型的碎片同时引入燃料组件引起的压降是显着的。然而，碎片按颗粒碎片的顺序引入燃料组件，