Development of Identification Method of Defects Embedded in a Body by A.C.Electromagnetic CT Method Using Inverse Analysis of Frequency Response

利用频率响应反分析的交流电磁CT法识别体内缺陷的方法的开发

基本信息

批准号：
07555349
负责人：
KUBO Shiro
金额：
$ 1.41万
依托单位：
Osaka University
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (A)
财政年份：
1995
资助国家：
日本
起止时间：
1995 至 1997
项目状态：
已结题

项目摘要

The present investigators proposed the D.C.electric potential CT (computed tomography) method for identification of two- and three- dimensional cracks embedded in an electric conductive body. The usefulness of the method was shown by numerical simulations and experiments. In this study, by extending the D.C.electric potential CT (computed tomography) method, A.C.electric potential CT defect identification method was proposed, in which electric potential distribution for several A.C.frequencies were used to identify the crack. The main conclusions obtained are summarized in the followings.1. Electromagnetic field of cracked body was analyzed using boundary element method to construct calibration relation between A.C.potential and crack length.2. A.C.electric potential distributions were measured for a body with a through crack. It was found that the calibration relation worked well.3. The electric potential distribution was calculated, in the case that the frequency was high and the skin effect was significant.4. Electric potential distribution in a three-dimensional surface crack was measured. It was found the electric potential distributions in the limits of high and low frequencies may be effective to identify the crack.5. Crack identification was made using full three-dimensional electromagnetic field analysis. It was found that the method was useful.6. For the identification of plural cracks fusion type genetic algorithm was proposed.7. Identifiction of interface crack in dissimilar materials was made by extending the method. Nemerical simulations and experiments showed the usefulness of the method.

本研究人员提出了D.C.电势CT（计算机断层扫描）方法，用于鉴定嵌入在电导体中的二维裂纹和三维裂纹。该方法的有用性通过数值模拟和实验显示。在这项研究中，提出了通过扩展电势CT（计算机断层扫描）方法，提出了电势CT缺陷鉴定方法，其中使用了几种A.C的电势分布。以下内容总结了所获得的主要结论。1。使用边界元素方法分析了破裂体的电磁场，以构建A.C.电位和裂纹长度之间的校准关系。2。 A.C.电势分布是针对具有通过裂纹的身体的。发现校准关系效果很好。3。计算电势分布，如果频率高并且皮肤效应显着。4。测量了三维表面裂纹中的电势分布。发现在高频和低频的范围内的电势分布可能有效地识别裂纹5。使用完整的三维电磁场分析进行裂纹识别。发现该方法很有用。6。为了鉴定复数裂纹融合型遗传算法。7。通过扩展该方法，可以识别不同材料中界面裂纹的识别。 nemerical模拟和实验显示了该方法的有用性。