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04:54
A Stable Phantom Material for Optical and Acoustic Imaging
Published on: June 16, 2023
Reflection of underwater sound from surface waves.
Chris T Tindle1, Grant B Deane, James C Preisig
1Physics Department, University of Auckland, Bag, Auckland, New Zealand.
The Journal of the Acoustical Society of America
|January 29, 2009
Summary
Underwater sound reflection from surface waves causes complex waveform variations. Wavefront modeling accurately predicts these interference patterns, matching experimental results.
Area of Science:
- Acoustics
- Oceanography
- Wave physics
Background:
- Surface waves significantly impact underwater sound propagation.
- Understanding sound reflection is crucial for sonar and underwater communication.
Purpose of the Study:
- To experimentally measure and theoretically model underwater sound reflection from surface waves.
- To analyze the effects of wave crests on sound focusing and waveform complexity.
Main Methods:
- Tank experiment to record sound reflection.
- Wavefront modeling to simulate sound propagation and interference.
- Comparison of theoretical predictions with experimental data.
Main Results:
- Surface wave reflection causes focusing and caustics, leading to rapid waveform changes.
- Theoretical modeling shows interference of three surface-reflected eigenrays per wave crest.
- Experimental and theoretical results show good agreement, even in shadow zones.
Conclusions:
- Surface wave dynamics critically influence underwater acoustic signals.
- Wavefront modeling provides a reliable tool for predicting complex reflection phenomena.
- The study validates theoretical predictions against experimental observations in challenging acoustic environments.
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