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Analysis of the acoustic scattering at variable incidences from an extra thin cylindrical shell bounded by
Touraine1, Haumesser, Decultot
1Laboratoire d'Acoustique Ultrasonore et d'Electronique, LAUE, UPRESA CNRS 6068, Universite du Havre, France.
The Journal of the Acoustical Society of America
|December 7, 2000
Summary
This study examines acoustic backscattering from submerged cylindrical shells with endcaps. Findings reveal how shell geometry influences wave scattering, aiding in the identification of complex underwater objects.
Area of Science:
- Underwater acoustics
- Acoustic wave scattering
- Shell structure analysis
Background:
- Acoustic backscattering is crucial for underwater object identification.
- Complex geometries like shells with endcaps present unique scattering challenges.
- Understanding wave propagation in shells informs sonar and remote sensing.
Purpose of the Study:
- To experimentally investigate acoustic backscattering from air-filled submerged cylindrical shells with hemispherical endcaps.
- To analyze acoustic wave scattering processes at variable incidences.
- To contribute to the identification of geometrically complex underwater objects.
Main Methods:
- Experimental approach using acoustic backscattering measurements.
- Variable incidence angles (axial and normal) were explored.
- Analysis of time and frequency domain data to identify wave types (S0 and T0).
Main Results:
- Distinct angular zones of acoustic response were observed based on excitation.
- Specific echo series were identified and related to wave types (S0, T0).
- Comparison with canonical objects highlighted the influence of endcaps and finite length.
Conclusions:
- The study successfully characterized acoustic scattering from complex shell structures.
- Endcaps and finite length significantly influence the acoustic response of cylindrical shells.
- This research enhances the knowledge base for identifying complex underwater targets using acoustics.
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