ISSN:
1013-9826
Source:
Scientific.Net: Materials Science & Technology / Trans Tech Publications Archiv 1984-2008
Topics:
Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
Notes:
In this study, elastic waves of ultrasonic and acoustic emission were used to evaluate thepropagation characteristic of the wave in pipe, and study on mode conversion of the elastic wavedue to the cracks in the pipe was also performed. An acoustic emission (AE) sensor was used toreceive the propagated ultrasonic wave. AE technique has a merit that it can identify the receivedultrasonic wave by the analysis of the AE parameters such as count, energy, frequency, durationtime and amplitude. For transmitting and receiving of the wave, a wedge for universal angle wasmanufactured. The optimum angles for transmitting of ultrasonic wave and signal receiving at theattached AE sensor on the pipe were determined. Theoretical dispersion curve was compared withthe results of the time-frequency analysis based on the wavelet transformation. The received modesshowed a good agreement with theoretical one. The used ultrasonic sensor was 1MHz, and AEsensor was broadband (100kHz – 1200kHz). The artificial cracks were induced in the pipe tomeasure the propagation characteristics of the elastic wave for the cracks. AE parameters for thereceived signals were also varied with the crack types in the pipe. AE parameters of amplitude andduration time were more effective factors than the analysis of mode conversion for evaluation of thecracks in the pipe
Type of Medium:
Electronic Resource
URL:
http://www.tib-hannover.de/fulltexts/2011/0528/01/54/transtech_doi~10.4028%252Fwww.scientific.net%252FKEM.345-346.1323.pdf
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