Higher and sub-harmonic Lamb wave mode generation due to debond-induced contact nonlinearity
| Autor: | C. R. Bijudas, Anurup Guha |
|---|---|
| Rok vydání: | 2016 |
| Předmět: |
Signal processing
Materials science Acoustics Fast Fourier transform 02 engineering and technology 021001 nanoscience & nanotechnology 01 natural sciences Piezoelectricity symbols.namesake Lamb waves Amplitude Fourier transform 0103 physical sciences Harmonic symbols 0210 nano-technology 010301 acoustics Excitation |
| Zdroj: | SPIE Proceedings. |
| ISSN: | 0277-786X |
| DOI: | 10.1117/12.2218611 |
| Popis: | Non-cumulative higher and sub-harmonic Lamb wave mode generation as a result of partial-debond of piezoelectric wafer transducers (PWT) bonded onto an Aluminium plate, is numerically investigated and experimentally validated. The influence of excitation frequency on the extent of nonlinearity due to clapping mechanism of the partially-debonded PWTs is discussed. A set of specific frequency range is arrived at based on the Eigen-value and Harmonic analyses of PWTs used in the model. It is found that, at these frequencies, which are integral multiple of the first width-direction mode of a PWT, significantly higher amplitudes of higher-harmonics are observed. It is also seen that at specific debond-positions and lengths, sharp sub-harmonics in addition to higher-harmonics are present. Signal processing is carried out using Fast Fourier transform, which is normalized for comparisons. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
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