小径管周向裂纹涡流检测仿真与试验研究

Simulation and experimental study on eddy current testing of circumferential cracks in small diameter tubes

通过电磁场仿真软件建立三维仿真模型,分析传统Bobbin探头和横向放置的圆柱形探头在小径管中的涡流场分布,结果表明周向裂纹对后者产生的涡流场扰动更加明显,在裂纹下部能提升40%的平均涡流密度。同时基于仿真研究设计出一种新型的基于横向激励的探头,用所设计的探头对铜管试件的人工周向裂纹进行检测,可以有效地检测出长度为2 mm的周向裂纹,且对更窄的自然周向裂纹具有潜在的高灵敏度。

The three-dimensional simulation model was established through electromagnetic field simulation software to analyze the eddy current field distribution of traditional Bobbin probe and transverse cylindrical probe in small diameter tube.The results show that the circumferential crack has more obvious disturbance to the eddy current field generated by the latter, and the average eddy current density can be increased by 40% under the cracks.And based on the simulation research, a new type of probe based on transverse excitation was designed to detect the artificial circumferential crack of the copper tube specimen with the designed probe, which can effectively detect the circumferential crack with a length of 2 mm, and has potential high sensitivity to the narrower natural circumferential crack.