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04:54
A Stable Phantom Material for Optical and Acoustic Imaging
Published on: June 16, 2023
Coherent reflection from surface gravity water waves during reciprocal acoustic transmissions
Mohsen Badiey1, Aijun Song, Kevin B Smith
1College of Earth, Ocean, and Environment, University of Delaware, 007 Robinson Hall, Newark, Delaware 19716, USA. badiey@udel.edu
The Journal of the Acoustical Society of America
|October 9, 2012
Summary
Moving surface waves create intense underwater acoustic signals. A new model accurately simulates these dynamic sea surface acoustic returns, enhancing ocean acoustics understanding.
Area of Science:
- Oceanography
- Acoustics
- Wave dynamics
Background:
- Underwater acoustic propagation is influenced by sea surface conditions.
- Previous models did not fully capture dynamic sea surface effects on acoustics.
Purpose of the Study:
- To investigate the acoustic returns generated by moving surface waves.
- To develop and validate a model for dynamic sea surface acoustic interactions.
Main Methods:
- Conducted reciprocal acoustic transmissions between seafloor transceivers at 100m depth.
- Utilized a two-dimensional parabolic equation model incorporating an evolving sea surface.
Main Results:
- Observed focused, intense coherent acoustic returns correlated with surface wave crests.
- Demonstrated that acoustic delay varied with propagation direction relative to wave crests.
- The parabolic equation model showed qualitative agreement with experimental data.
Conclusions:
- Moving surface waves are a significant source of dynamic acoustic returns.
- The developed model provides a viable approach for simulating sea surface acoustic effects.
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