Ultrasonic Guided-Wave Mode Identification in Pipe by Using Air-Coupled Transducer and Time-Frequency Analysis

Abstract:

For efficient NDE of pipes, essential components of power plant facilities, ultrasonic guided waves were generated and received applying an air-coupled transducer and comb one as non-contact technology. Mode generation and selection were predicted based on theoretical dispersive curve and the element space of a comb transducer. In addition, a receiving angle of the air-coupled transducer was determined to acquire the predicted modes by theoretical phase velocity of each mode. Theoretical dispersive curve was compared with the results of the time-frequency spectroscopes based on the wavelet transform and 2D-FFT to identify the characteristics of the received mode. The received modes show a good agreement with the predicted ones.

• Periodical: Key Engineering Materials (Volumes 321-323)
• Pages: 804-807
• DOI: https://doi.org/10.4028/www.scientific.net/KEM.321-323.804
• Online since: October 2006
• Authors: Ik Keun Park, Hyun Mook Kim, Yong Kwon Kim, Yong Sang Cho
• Keywords: 2D-FFT, Air-Coupled Transducer, Guided Wave, Wavelet

References

[1] J. L. Rose and Y. H. Cho : Safety & NDT 95(1995), pp.101-115.

[2] H. J. Shin and J. L. Rose : Journal of Nondestructive Evaluation, Vol. 17-1(1998), pp.27-36.

[3] A. E. Bahrawy : Journal of Sound Vibration, Vol. 170-2(1994), pp.145-160.

[4] B. Djordjevic : Proc. Ultrasonic International-1993(1993), Vienna, Austria.

[5] D. A. Oursler and J. W. Wagner : Material Evaluation, Vol. 53(1995), pp.593-597.

[6] W. M. D. Wright, D. W. Schindel and D. A. Hutchins : Journal of Acoustical Society of America., Vol. 95(1994), pp.2567-2575.