中国物理B ›› 2016, Vol. 25 ›› Issue (12): 124304-124304.doi: 10.1088/1674-1056/25/12/124304

• SPECIAL TOPIC—Acoustics • 上一篇    下一篇

Quantitative damage imaging using Lamb wave diffraction tomography

Hai-Yan Zhang(张海燕), Min Ruan(阮敏), Wen-Fa Zhu(朱文发), Xiao-Dong Chai(柴晓冬)   

  1. 1. School of Communication and Information Engineering, Shanghai University, Shanghai 200444, China;
    2. School of Urban Railway Transportation, Shanghai University of Engineering Science, Shanghai 201620, China
  • 收稿日期:2016-07-05 修回日期:2016-08-07 出版日期:2016-12-05 发布日期:2016-12-05
  • 通讯作者: Hai-Yan Zhang, Wen-Fa Zhu E-mail:hyzh@shu.edu.cn;zhuwenfa1986@163.com
  • 基金资助:

    Project supported by the National Natural Science Foundation of China (Grant Nos. 11474195, 11274226, 11674214, and 51478258).

Quantitative damage imaging using Lamb wave diffraction tomography

Hai-Yan Zhang(张海燕)1, Min Ruan(阮敏)1, Wen-Fa Zhu(朱文发)1,2, Xiao-Dong Chai(柴晓冬)2   

  1. 1. School of Communication and Information Engineering, Shanghai University, Shanghai 200444, China;
    2. School of Urban Railway Transportation, Shanghai University of Engineering Science, Shanghai 201620, China
  • Received:2016-07-05 Revised:2016-08-07 Online:2016-12-05 Published:2016-12-05
  • Contact: Hai-Yan Zhang, Wen-Fa Zhu E-mail:hyzh@shu.edu.cn;zhuwenfa1986@163.com
  • Supported by:

    Project supported by the National Natural Science Foundation of China (Grant Nos. 11474195, 11274226, 11674214, and 51478258).

摘要:

In this paper, we investigate the diffraction tomography for quantitative imaging damages of partly through-thickness holes with various shapes in isotropic plates by using converted and non-converted scattered Lamb waves generated numerically. Finite element simulations are carried out to provide the scattered wave data. The validity of the finite element model is confirmed by the comparison of scattering directivity pattern (SDP) of circle blind hole damage between the finite element simulations and the analytical results. The imaging method is based on a theoretical relation between the one-dimensional (1D) Fourier transform of the scattered projection and two-dimensional (2D) spatial Fourier transform of the scattering object. A quantitative image of the damage is obtained by carrying out the 2D inverse Fourier transform of the scattering object. The proposed approach employs a circle transducer network containing forward and backward projections, which lead to so-called transmission mode (TMDT) and reflection mode diffraction tomography (RMDT), respectively. The reconstructed results of the two projections for a non-converted S0 scattered mode are investigated to illuminate the influence of the scattering field data. The results show that Lamb wave diffraction tomography using the combination of TMDT and RMDT improves the imaging effect compared with by using only the TMDT or RMDT. The scattered data of the converted A0 mode are also used to assess the performance of the diffraction tomography method. It is found that the circle and elliptical shaped damages can still be reasonably identified from the reconstructed images while the reconstructed results of other complex shaped damages like crisscross rectangles and racecourse are relatively poor.

关键词: Lamb waves, diffraction tomography, damage identification, Fourier diffraction theorem

Abstract:

In this paper, we investigate the diffraction tomography for quantitative imaging damages of partly through-thickness holes with various shapes in isotropic plates by using converted and non-converted scattered Lamb waves generated numerically. Finite element simulations are carried out to provide the scattered wave data. The validity of the finite element model is confirmed by the comparison of scattering directivity pattern (SDP) of circle blind hole damage between the finite element simulations and the analytical results. The imaging method is based on a theoretical relation between the one-dimensional (1D) Fourier transform of the scattered projection and two-dimensional (2D) spatial Fourier transform of the scattering object. A quantitative image of the damage is obtained by carrying out the 2D inverse Fourier transform of the scattering object. The proposed approach employs a circle transducer network containing forward and backward projections, which lead to so-called transmission mode (TMDT) and reflection mode diffraction tomography (RMDT), respectively. The reconstructed results of the two projections for a non-converted S0 scattered mode are investigated to illuminate the influence of the scattering field data. The results show that Lamb wave diffraction tomography using the combination of TMDT and RMDT improves the imaging effect compared with by using only the TMDT or RMDT. The scattered data of the converted A0 mode are also used to assess the performance of the diffraction tomography method. It is found that the circle and elliptical shaped damages can still be reasonably identified from the reconstructed images while the reconstructed results of other complex shaped damages like crisscross rectangles and racecourse are relatively poor.

Key words: Lamb waves, diffraction tomography, damage identification, Fourier diffraction theorem

中图分类号:  (General linear acoustics)

  • 43.20.+g
43.35.+d (Ultrasonics, quantum acoustics, and physical effects of sound)