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Fracture source location in thin plates using the wavelet transform of dispersive waves
1Div. of Mech. Eng., Wonkwang Univ., Jeonbuk, Korea. hjjeong@wonnms.wonkwang.ac.kr
Summary
This study introduces a new signal processing method using wavelet transform (WT) for accurate acoustic emission source location in thin plates. The WT method precisely determines wave arrival times, improving fracture location accuracy.
Area of Science:
- Acoustics
- Signal Processing
- Materials Science
Background:
- Accurate source location is crucial for analyzing material failures.
- Wave propagation in dispersive media, like thin plates, complicates traditional location methods.
- Dispersive waves exhibit frequency-dependent behavior, impacting signal arrival times.
Purpose of the Study:
- To develop and validate a novel signal processing approach for acoustic emission source location.
- To leverage dispersive wave characteristics for enhanced location accuracy.
- To compare the effectiveness of the proposed method with existing techniques.
Main Methods:
- Utilized the wavelet transform (WT) to analyze time-frequency data of acoustic emission signals.
- Identified and tracked specific frequency components of dispersive waves (S(0) and A(0) Lamb waves).
- Measured frequency-dependent arrival times and group velocities of Lamb waves.
Main Results:
- The wavelet transform method accurately determined frequency-dependent arrival times.
- Group velocities for S(0) and A(0) Lamb waves were precisely measured on an aluminum plate.
- Source location results obtained using WT showed strong agreement with true source locations.
- WT method performance was comparable to the cross-correlation technique.
Conclusions:
- The wavelet transform provides an effective method for acoustic emission source location in thin plates.
- Utilizing dispersive wave properties significantly improves location accuracy.
- The WT approach offers a reliable alternative to traditional methods like cross-correlation.
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