Jung Do-Yun, Choi Young-Chul, Chung Byun-Young
Korea Atomic Energy Research Institute, Daejeon 34057, Republic of Korea.
Sensors (Basel). 2024 Nov 22;24(23):7456. doi: 10.3390/s24237456.
This study presents a method to add a crack analysis algorithm to the Acoustic Leak Monitoring System (ALMS) to detect and evaluate the crack growth process in the primary system piping of nuclear power plants. To achieve this, a fracture test was conducted by applying stepwise loading to welded specimens that simulate the cold leg section, and acoustic emission (AE) signals were measured in relation to the increase in strain using an AE testing system. The experimental results indicated that the stability and instability of cracks could be assessed through the Kaiser effect and the Felicity effect when detecting crack growth using AE signals. Additionally, by utilizing both root mean square (RMS) and amplitude parameters simultaneously to calculate the -value, it was confirmed that the RMS-based -value minimizes the effects of AE signal attenuation and allows for a more stable assessment of crack progression. This demonstrates that the RMS, which reflects signal energy, is effective for real-time monitoring of the crack growth state. Finally, the results of this study suggest the potential for real-time crack monitoring using AE data in piping systems of critical structures, such as nuclear power plants; by adding a simple AE analysis method to the ALMS system, a practical approach has been derived that enhances the safety of the structure and allows for quantitative assessment of crack progression. Future research is expected to further refine the AE parameters and algorithms, leading to the advancement of safety monitoring systems in various industrial settings.
本研究提出了一种在声学泄漏监测系统（ALMS）中添加裂纹分析算法的方法，以检测和评估核电站一回路系统管道中的裂纹扩展过程。为此，通过对模拟冷段的焊接试样施加逐步加载进行断裂试验，并使用声发射（AE）测试系统测量与应变增加相关的声发射信号。实验结果表明，在使用声发射信号检测裂纹扩展时，可通过凯泽效应和费利西蒂效应评估裂纹的稳定性和失稳情况。此外，通过同时利用均方根（RMS）和幅度参数来计算 - 值，证实基于均方根的 - 值可将声发射信号衰减的影响降至最低，并能更稳定地评估裂纹扩展情况。这表明反映信号能量的均方根对于实时监测裂纹扩展状态是有效的。最后，本研究结果表明在核电站等关键结构的管道系统中利用声发射数据进行实时裂纹监测具有潜力；通过在ALMS系统中添加一种简单的声发射分析方法，得出了一种实用方法，可提高结构安全性并实现对裂纹扩展的定量评估。未来的研究有望进一步完善声发射参数和算法，推动各种工业环境中安全监测系统的发展。
