摘要
本文依据远场涡流检测中场的分布特点对远场涡流模型进行了合理的简化,建立了有限元分析模型,并完成了二维及三维有限元数值分析,给出了缺损附近的磁场、涡流及波印亭矢量的分布,预估了远场技术中三维探头的缺损响应,结合实验结果初步解释了由实验观察到的而至今未被理解的一些远场现象。最后着重分析了周向缺损与轴向缺损的探头信号的差异,并对远场技术缺损的检测机理作了较为细致的探讨,得到了一些重要结论。
Based on the characteristics of the field distributions in Remote Field Eddy Current (RFEC), a simplified RFEC model is proposed for the modelling of 3-D defect responses. The magnetic field densities, eddy cunent densities and Poynting vector distributions around defects are given by using 2-D and 3-D FEM calculations. The predictions of 3-D probe responses to the defects oriented circumferentially and axially are also shown respectively. Some remote field phenomena which had not been understood are observed by experimentations and explained with the help of calculated results. Finally, the differences between the probe responses caused by the two kinds of 3-D defects are indicated and the defect detection mechanism of RFEC inspection technique is discussed preliminarily. Some important conclusions have been obtained.
基金
国家自然科学基金
航空科学基金
关键词
缺陷检查
有限元分析
涡旋流动
eddy current testing, defect inspection, finite element analysis, remote field eddy current, defect response
