Ultrasonic Guided-Wave Mode Identification in Pipe by Using Air-Coupled Transducer and Time-Frequency Analysis
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.
Seung-Seok Lee, Joon Hyun Lee, Ik Keun Park, Sung-Jin Song, Man Yong Choi
I. K. Park et al., "Ultrasonic Guided-Wave Mode Identification in Pipe by Using Air-Coupled Transducer and Time-Frequency Analysis", Key Engineering Materials, Vols. 321-323, pp. 804-807, 2006