基于超声导波的管道缺陷量化评估仿真研究

摘要

超声导波是近年新兴的无损检测技术,相比超声检测和漏磁检测等传统方法,它可提供大范围、全面高效的检测,因此受到越来越多的关注.在基于超声导波的管道缺陷检测中,普遍采用脉冲回波方法,即根据反射回波信号的分析结果获取缺陷信息,目前此技术已可实现管道缺陷的识别和定位.但由于实际管道缺陷形态不规则,产生的反射回波信号往往很复杂,目前还不能实现管道缺陷的量化检测.本文针对此问题,通过有限元仿真方法研究超声导波与管道缺陷的交互过程,提出利用缺陷前后边界分别产生的两个反射信号进行缺陷轴向尺寸的量化评估方法,并进一步通过有限元仿真验证了结论.%The ultrasonic guided-waves (UGW) is an emerging non-destructive testing technique in recent years.Compared with conventional inspection techniques, such as ultrasonic inspection and magnetic flux leakage testing, the UGW can enable long-range, comprehensive and efficient inspection, thus arousing more attention, especially for pipe inspection.In pipe inspection based on the UGW, the pulse-echo method is widely used with the defect information obtained by conducting an analysis of the echo signal.The UGW have currently realized the reorganization and location of pipe defects.However, due to the irregular shape of the actual pipe defect, the reflected echo signal is often very complex, and it cannot achieve the quantitative detection of pipe defects.In this paper, the interaction between ultrasonic guided waves and pipe defect is studied by the finite-element (FE) numerical simulation.A quantitative evaluation method for axial length of pipe defect is proposed by concerning two boundary reflection signals generated at the front and rear edges of defects, with the conclusions further verified by the FE simulation test.