During the long-term cooling (LTC) phase of a loss-of-coolant accident (LOCA) in a pressurized water reactor (PWR), water is supplied from the containment sump to the reactor coolant system (RCS) by the flooded sump water to the Reactor Vessel (RV) through the broken pipes. As part of the technical efforts for resolving GSI-191 [( Reid and Crytzer, May. 2007) 1, consideration is needed for the consequences of debris penetrating the sump screen and propagating downstream into the RV. Injection of debris (fiberglass) into the RV during the LTC recirculation phase needs special attention to assure that reactor core cooling is maintained. The point of concern is the potential for debris to adversely affect the reactor core flow paths or heat transfer [2]. However, all the experiments for proving the coolability of RV have been done with the assumption of the most of debris would be transferred to the RV and the bottom nozzle of the FAs.

The purpose of the tests is to quantify the amount of the debris that would be accumulated at the lower plenum and the debris that passes through the FAs since non-conservatism of other researches assumptions that have been used in the past experimental or analytical programs.

在压水反应堆 (PWR) 中冷却剂损失事故 (LOCA) 的长期冷却 (LTC) 阶段，水从安全壳水槽通过溢流水槽水供应到反应堆冷却剂系统 (RCS)通过破损的管道到达反应堆容器 (RV)。作为解决 GSI-191 [（Reid 和 Crytzer，2007 年 5 月）1 技术工作的一部分，需要考虑碎片穿透集水槽筛网并向下游传播到 RV 中的后果。在 LTC 再循环阶段将碎片（玻璃纤维）注入 RV 需要特别注意以确保维持反应堆堆芯冷却。关注点是碎片可能对反应堆堆芯流动路径或热传递产生不利影响 [2]。然而，

测试的目的是量化将在下部压力通风系统中积聚的碎片数量以及由于过去实验或分析程序中使用的其他研究假设的非保守性而穿过 FA 的碎片数量。