堆芯功率分布对CCTF试验再淹没现象影响的评价研究

以圆柱形堆芯试验装置（CCTF）为研究对象，采用轻水堆冷却系统事故工况的瞬态行为最佳估算程序（RELAP5）和自主化堆工设计与安全分析程序（LOCUST），开展堆芯功率分布对CCTF C2-SH2（Run54）试验工况再淹没现象影响的评价研究。研究表明:①计算所得下降段压降、堆芯压降、堆芯出口蒸汽质量流量等计算结果与试验结果吻合较好；②对于堆芯1.015 m处平均通道包壳峰值温度的计算，RELAP5和LOCUST程序计算的包壳峰值温度分别为816 K和813 K，试验结果为898 K，计算值比试验值低约82 K，平均通道包壳温度最后稳定在400 K左右，计算结果与试验结果一致。因此，本研究结果表明LOCUST程序能够较好地对大破口失水事故（LBLOCA）中再淹没阶段的瞬态过程进行模拟。 

Analysis on Effect of Control Rod Worth in Extrapolation in Criticality Experiment

The application effect of the control rod worth in the criticality extrapolation experiment is studied. The criticality extrapolation experiment is conducted on a zero power reactor, and the analysis is carried out by 2 extrapolation methods, i.e., with and without the consideration of the control rod worth, based on the neutron count rate data. The results indicate that the control rod worth is with great effect on the extrapolation results in the first few extrapolation steps, and the extrapolation 1/2 adding control rod position would exceed the measured critical control rod position without taking consideration of the control rod worth. The extrapolation method taking the control rod worth into consideration is more precise, with better results.