Analysis of wave propagation in anisotropic materials and application to NDE

各向异性材料中的波传播分析及其在无损检测中的应用

• 批准号: 09650527
• 负责人: HIROSE Sohichi
• 金额: $ 2.24万
• 依托单位: Tokyo Institute of Technology (1998-1999)Okayama University (1997)
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (C)
• 财政年份: 1997
• 资助国家: 日本
• 起止时间: 1997 至 1999
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-09650527/
• 关键词: anisotropic media; scattering; boundary element method; fundamental solution; NDE; angled beam ultrasonic testing; numerical simulation; 異方性; 入射パターン; 散乱解析; き裂; 超音波実験; 定量的非破壊評価; 異方弾性体; 波動解析; 可視化; 散乱パターン; グリーン関数; 選点法; ガラーキン法; 水浸超音波法

Dynamic behaviors of elastic waves in anisotropic media are much different from those in isotropic media since elastic wave speeds depend on the directions of wave propagation. It is, therefore, necessary to develop the analysis for scattering and propagation of elastic waves for quantitative ultrasonic nondestructive evaluation for anisotropic materials. In this paper, numerical and experimental approaches are pursued to investigate the effect of anisotropy on the characteristics of elastic waves and are applied to the ultrasonic testing to detect quantitatively a defect in a thick anisotropic plate. The main results are obtained as follows: 1. The program code is developed to analyze the dynamic behaviors of elastic waves by a volumetric defect in an anisotropic solid of infinite extent. The method is based on a time domain boundary integral equation in conjunction with a collocation point method. Numerical results are visualized for scattering and propagation around defects subjected to various conditions of incident waves and material constants. 2. A boundary integral equation method is also developed for the scattering problem by a crack in an anisotropic solid, where the hypersingular integrals are regularized using the Galerkin method. 3. Ultrasonic experiments with angled beam transducers are carried out for a thick steel plate with artificial cylindrical defects. It is shown that as the incident wave angle increases, the effect of anisotropy increases, which implies that the accuracy of the nondestructive testing may decrease unless appropriate remedy is given. 4. All processes of ultrasonic experiments including incidence, scattering and radiation are numerically simulated. Good agreement is obtained between theory and experiment, which will give useful information for quantitative ultrasonic evaluation for anisotropic materials.

各向异性介质中弹性波的动态行为与各向同性介质中的动态行为有很大不同，因为弹性波速度取决于波传播的方向。因此，有必要发展弹性波的散射和传播分析方法，对各向异性材料进行定量超声无损评价。本文采用数值和实验方法来研究各向异性对弹性波特性的影响，并将其应用于超声检测以定量检测各向异性厚板中的缺陷。主要研究结果如下： 1.开发了程序代码来分析无限范围各向异性固体中体积缺陷引起的弹性波的动力行为。该方法基于时域边界积分方程和搭配点法。在各种入射波和材料常数条件下，缺陷周围的散射和传播的数值结果可视化。 2.针对各向异性固体中裂纹的散射问题，还提出了边界积分方程方法，其中超奇异积分采用伽辽金法进行正则化。 3.对具有人工圆柱形缺陷的厚钢板进行斜波束换能器超声实验。结果表明，随着入射波角度的增加，各向异性的影响增加，这意味着除非采取适当的补救措施，否则无损检测的精度可能会降低。 4.对超声波实验的入射、散射、辐射等全过程进行数值模拟。理论与实验取得了良好的一致性，为各向异性材料的定量超声评价提供了有用的信息。

项目成果

桂健太郎,廣瀬壮一: "弾性波動の散乱特性に及ぼす異方性の影響"第27回土木学会関東支部技術研究発表会概要集. (2000)

Kentaro Katsura、Soichi Hirose：“各向异性对弹性波散射特性的影响”第 27 届日本土木学会关东分会技术研究报告摘要集（2000 年）。

S. Hirose: "Dynamic analysis for a crack in anisotropic elastic solid"Proc. 16th Japan National Symp. on Boundary Element Methods, JACOME. 16. 13-17 (1999)

S. Hirose：“各向异性弹性固体中裂纹的动态分析”Proc。

S. Hirose: "Simulation of ultrasonic wave scattering and inverse analysis using integral equations"J. Japanese Soc. Non-destructive Inspection. 47. 300-306 (1998)

S. Hirose：“利用积分方程模拟超声波散射和反分析”J。

廣瀬壮一: "異方弾性体中のき裂に対する動的解析"境界要素法論文集. 第16巻. 13-17 (1999)

Soichi Hirose：“各向异性弹性体裂纹的动态分析”边界元法论文，第 16 卷，13-17 (1999)。

S.Hirose and K.Katsura: "Elastic wave scattering by various defects in anisotropic materials"Review of Progress in Quantitative Nondestructive Evaluation. 第19巻. (2000)

S. Hirose 和 K. Katsura：“各向异性材料中各种缺陷引起的弹性波散射”定量无损评估进展回顾第 19 卷（2000 年）。