涡流检测中识别缺陷形状的一种新方法

基金项目: 国家自然科学基金资助项目(10371096)

New Algorithm of Identifying the Shape of Flaws or Cracks in Eddy Current Testing

摘要: 涡流检测反演技术是一种非常重要的反演缺陷形状尺寸的无损检测方法．运用Dirichlet边界条件下涡流检测反演的远场区域导数，构造了反演缺陷形状的一种新算法，并且给出了二维及三维的算例，数值反演的结果与实际缺陷吻合得较好．从而说明了:对较小的波数,即使用较少的入射和观测方向的远场测量信息,亦可得到未知缺陷形状的一个合理的重构,算法是可行的、正确的．
- 涡流检测 /
- 区域导数 /
- Nystr?m方法
Abstract: Eddy-current inverse technique is a very important method to reconstruct the shape of flaws or cracks.Using the domain derivative of the far-field pattern for eddy-current inverse problem with Dirichlet boundary condition,a new algorithm to recover the shape of cracks was constructed and some numerical examples were given.The algorithm demonstrates that the algorithm is feasible and correct for obtaining a reasonable reconstruction of a shape of flaws or cracks from the far-field measurements even though using less data of directions of incidence and observations for fewer wave numbers are gived.
- eddy current /
- domain derivative /
- Nystrê method

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