脉冲涡流检测中参数影响的仿真分析与实验研究

脉冲涡流检测过程中传感器尺寸及激励参数对检测结果影响较大,对其进行优化设计可提高检测系统的性能。在分析矩形脉冲涡流传感器工作原理的基础上,采用ANSYS仿真软件建立了脉冲涡流的仿真模型,仿真分析了传感器尺寸变化对铝板中涡流衰减规律的影响,激励脉冲频率和占空比变化对缺陷检测灵敏度的影响,仿真结果表明:当激励线圈长度增加时,涡流在铝板中的衰减速度变慢,而当激励线圈宽度和高度增加时,涡流在铝板中的衰减速度变快;激励频率与占空比对缺陷检测灵敏度的影响与被测试件厚度有关,对于厚度较大的板材,应适当降低激励频率并提高占空比。最后采用实验的方法对仿真结果进行了验证,实验与仿真结果相一致,证明了仿真结论的正确性。

Simulation Analysis and Experimental Research on Parameter Influence in Pulsed Eddy Current Nondestructive Testing Technique

The dimension of probe and the exciting parameters have an obvious influence on the result of pulsed eddy current (PEC) nondestructive testing, the capability of the PEC inspection system can be improved by optimizing these parameters. Based on the analysis of the principle of PEC, the PEC model is established by ANSYS finite element simulation software to analyze the influence of the variation of probe dimension on the eddy current decay law and that of the change of exciting frequency and duty cycle on the detecting sensitivity. The simulation results show that the attenuation of the eddy current slows down with the increase of exciting coil length, and the attenuation of the eddy current quickens with the increase of exciting coil width and highness. The influence of exciting frequency and duty cycle on the detecting sensitivity of defect has a relationship with the specimen thickness, the exciting frequency should be appropriately decreased and the duty cycle increased in inspecting thick specimen. Finally, the results of simulation are testified by experiment methods, the agreement between simulation and experiment shows the correctness of simulation.