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Title: Frequency-Wavenumber Domain Filtering for Improved Damage Visualization

Abstract

This paper presents a technique for the analysis of full wavefield data in the wavenumber/frequency domain as an effective tool for damage detection, visualization and characterization. Full wavefield data contain a wealth of information regarding the space and time variation of propagating waves in damaged structural components. Such information can be used to evaluate the response spectrum in the frequency/wavenumber domain, which effectively separates incident waves from reflections caused by discontinuities encountered along the wave paths. This allows removing the injected wave from the overall response through simple filtering strategies, thus highlighting the presence of reflections associated to damage. The concept is first illustrated on analytical and numerically simulated data, and then tested on experimental results. In the experiments, full wavefield measurements are conveniently obtained using a Scanning Laser Doppler Vibrometer, which allows the detection of displacements and/or velocities over a user-defined grid, and it is able to provide the required spatial and time information in a timely manner. Tests performed on a simple aluminum plate with artificially seeded slits simulating longitudinal cracks, and on a disbonded tongue and groove joint show the effectiveness of the technique and its potential for application to the inspection of a variety of structuralmore » components.« less

Authors:
 [1]
  1. School of Aerospace Engineering, Georgia Institute of Technology, Atlanta, GA 30332 (United States)
Publication Date:
OSTI Identifier:
21054949
Resource Type:
Journal Article
Resource Relation:
Journal Name: AIP Conference Proceedings; Journal Volume: 894; Journal Issue: 1; Conference: Conference on review of progress in quantitative nondestructive evaluation, Portland, OR (United States), 30 Jul - 4 Aug 2006; Other Information: DOI: 10.1063/1.2718150; (c) 2007 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; ALUMINIUM; ALUMINIUM ALLOYS; COMPUTERIZED SIMULATION; CRACKS; DAMAGE; DETECTION; FILTERS; LASER RADIATION; NONDESTRUCTIVE TESTING; PLATES; REFLECTION; VARIATIONS; VELOCITY; WAVE PROPAGATION; WAVEGUIDES

Citation Formats

Ruzzene, M. Frequency-Wavenumber Domain Filtering for Improved Damage Visualization. United States: N. p., 2007. Web. doi:10.1063/1.2718150.
Ruzzene, M. Frequency-Wavenumber Domain Filtering for Improved Damage Visualization. United States. doi:10.1063/1.2718150.
Ruzzene, M. Wed . "Frequency-Wavenumber Domain Filtering for Improved Damage Visualization". United States. doi:10.1063/1.2718150.
@article{osti_21054949,
title = {Frequency-Wavenumber Domain Filtering for Improved Damage Visualization},
author = {Ruzzene, M.},
abstractNote = {This paper presents a technique for the analysis of full wavefield data in the wavenumber/frequency domain as an effective tool for damage detection, visualization and characterization. Full wavefield data contain a wealth of information regarding the space and time variation of propagating waves in damaged structural components. Such information can be used to evaluate the response spectrum in the frequency/wavenumber domain, which effectively separates incident waves from reflections caused by discontinuities encountered along the wave paths. This allows removing the injected wave from the overall response through simple filtering strategies, thus highlighting the presence of reflections associated to damage. The concept is first illustrated on analytical and numerically simulated data, and then tested on experimental results. In the experiments, full wavefield measurements are conveniently obtained using a Scanning Laser Doppler Vibrometer, which allows the detection of displacements and/or velocities over a user-defined grid, and it is able to provide the required spatial and time information in a timely manner. Tests performed on a simple aluminum plate with artificially seeded slits simulating longitudinal cracks, and on a disbonded tongue and groove joint show the effectiveness of the technique and its potential for application to the inspection of a variety of structural components.},
doi = {10.1063/1.2718150},
journal = {AIP Conference Proceedings},
number = 1,
volume = 894,
place = {United States},
year = {Wed Mar 21 00:00:00 EDT 2007},
month = {Wed Mar 21 00:00:00 EDT 2007}
}
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