管道焊缝区不同类型缺陷的导波检测有限元仿真

Finite Element Simulation of Guided Wave Detection of Different Defects in Pipeline Weld Zone

对于用常规的无损检测方法不能够有效地检测出管道焊缝中缺陷的问题,提出将展开法与时间反转法相结合,对焊缝中不同类型的缺陷进行检测。首先通过导波在管道上传播的位移-时程曲线确定焊缝的轴向位置,然后通过展开法判断焊缝中是否存在缺陷以及确定缺陷的周向位置。对焊缝中的小缺陷不容易识别的问题,运用时间反转法进行能量聚焦处理。数值模拟结果表明,展开法与时间反转法相结合能够对焊缝中的缺陷进行有效的识别。

Because conventional non-destructive testing methods cannot effectively detect defects in welds of pipeline,the expansion method combined with the time reversal method to detect different types of defects in the weld was proposed.Firstly, the axial position of the weld was determined by the displacement time history curve of the guided wave propagating on the pipeline, and then the expansion method was used to determine whether there are defects in the weld and the circumferential position of the defect. For the small defects in the weld which is difficult to identify, the time reversal method was used for energy focusing processing. The numerical simulation results show that the combination of expansion method and time reversal method can effectively identify defects in welds.