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Ao lamb mode radiation characteristics of air-coupled transducers in isotropic plates

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Abstract

The fundamental anti-symmetric Lamb mode (Ao) radiation characteristics of air-coupled transducers in isotropic (aluminium) plates were measured experimentally for the first time. To evaluate the radiation characteristics, experiments were performed by fixing the position of one of the transducers (either transmitter or receiver) and then moving other one (either receiver or transmitter) along the circumference of a circle, whose radius was equal to that of the distance of separation between the transducers. Experiments were conducted to evaluate the radiation pattern of 100 kHz, 200 kHz and 500 kHz air-coupled transducers in one mm and three mm thick aluminium plates. It is interesting to note that, Ao Lamb mode radiation pattern emitted by air-coupled transducers in isotropic plates is characterised by Gaussian curve.

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Abbreviations

θ :

orientation of air-coupled probe

ϕ :

direction of propagation of Ao mode or direction of radiation

V air :

acoustic wave velocity in air

V p :

phase velocity of Lamb mode

2h :

plate thickness

d :

distance of separation between transmitter and receiver

f :

frequency of excitation

ω :

circular frequency

k :

wavenumber

C L :

longitudinal wave velocity

C T :

shear wave velocity

A(r, t):

amplitude of Lamb wave at distance r and time t

A s (ϕ):

amplitude at source in ϕ direction

A max (r, ϕ):

peak amplitude at distance r from source in ϕ direction

f(t):

amplitude of signal in time domain

τ :

time

H(t):

imaginary part of Hilbert Transform

F(t):

Hilbert Transform

E(t):

amplitude of F(t)

E max :

peak of the transformed signal

E max ϕ :

peak of the transformed signal, which was captured in ϕ direction

e(ϕ):

normalized amplitude

a, b and c :

parameters in Gaussian distribution

R 2 :

goodness-of-fit

References

  1. Rose, J. L., “Ultrasonic Waves in Solid Media,” Cambridge University Press, pp. 101–128, 1999.

    Google Scholar 

  2. Nayfeh, A. H., “Wave Propagation in Layered Anisotropic Media: With Application to Composites,” Elsevier, 1995.

    Google Scholar 

  3. Castaings, M. and Hosten, B., “The Use of Electrostatic, Ultrasonic, Air-Coupled Transducers to Generate and Receive Lamb Waves in Anisotropic, Viscoelastic Plates,” Ultrasonics, Vol. 36, No. 1, pp. 361–365, 1998.

    Article  Google Scholar 

  4. Castaings, M. and Cawley, P., “The Generation, Propagation, and Detection of Lamb Waves in Plates using Air Coupled Ultrasonic Transducers,” The Journal of the Acoustical Society of America, Vol. 100, No. 5, pp. 3070–3077, 1996.

    Article  Google Scholar 

  5. Castaings, M., Cawley, P., Farlow, R., and Hayward, G., “Single Sided Inspection of Composite Materials Using Air Coupled Ultrasound,” Journal of Nondestructive Evaluation, Vol. 17, No. 1, pp. 37–45, 1998.

    Article  Google Scholar 

  6. Grandia, W., A. and Fortunko, C. M., “NDE Applications of Air-Coupled Ultrasonic Transducers,” Prof. of IEEE Ultrasonics Symposium, Vol. 1, pp. 697–709, 1995.

    Google Scholar 

  7. Kažys, R., Dem礮ko, A., Žukauskas, E., and Mažeika, L., “Air-Coupled Ultrasonic Investigation of Multi-Layered Composite Materials,” Ultrasonics, Vol. 44, No. pp. e819–e822, 2006.

    Article  Google Scholar 

  8. Žukauskas, E. and Kažys, R., “Investigation of the Delamination Type Defects Parameters in Multilayered GLARE3-3/2 Composite Material using Air-Coupled Ultrasonics Technique,” Ultragarsas (Ultrasound), Vol. 62, No. pp. 44–48, 2007.

    Google Scholar 

  9. Ramadas, C., Padiyar, M. J., Balasubramaniam, K., Joshi, M., and Krishnamurthy, C., “Delamination Size Detection using Time of Flight of Anti-Symmetric and Mode Converted Ao Mode of Guided Lamb Waves,” Journal of Intelligent Material Systems and Structures, Vol. 21, No. 8, pp. 817–825, 2010.

    Article  Google Scholar 

  10. Lowe, M. J. S., “Disperse Software Version 2.0. 16b,” Imperial College, 2003.

    Google Scholar 

  11. Kim, H., Jhang, K., Shin, M., and Kim, J., “A Noncontact NDE Method using a Laser Generated Focused-Lamb Wave with Enhanced Defect-Detection Ability and Spatial Resolution,” NDT & E International, Vol. 39, No. 4, pp. 312–319, 2006.

    Article  Google Scholar 

  12. Su, Z. and Ye, L., “Identification of Damage Using Lamb Waves,” Springer, pp. 144–145, 2009.

    Google Scholar 

  13. The MathWorks, Inc., “MATLAB Curve Fitting Toolbox,” 1994–2005.

    Google Scholar 

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Authors and Affiliations

  1. Composites Research Center, R & D E (E), DRDO, Pune, India, 411 015

    Ramadas Chennamsetti & Irfan Khan

Authors
  1. Ramadas Chennamsetti
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  2. Irfan Khan
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Correspondence to Ramadas Chennamsetti.

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Chennamsetti, R., Khan, I. Ao lamb mode radiation characteristics of air-coupled transducers in isotropic plates. Int. J. Precis. Eng. Manuf. 16, 121–125 (2015). https://doi.org/10.1007/s12541-015-0015-3

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  • DOI: https://doi.org/10.1007/s12541-015-0015-3

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