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Updated: May 31, 2026
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Published on: February 17, 2019
Sound scattering by free surface piercing and fluid-loaded cylindrical shells.
1School of Engineering and Materials, Queen Mary University of London, London E1 4NS, UK.
Summary
Acoustic invisibility is achievable for a flexible cylindrical shell in shallow water. This can be attained by applying a specific oscillating pressure load to the shell, minimizing sound scattering and transmission.
Area of Science:
- Acoustics
- Structural Dynamics
- Fluid Mechanics
Background:
- Underwater acoustic applications often involve sound scattering from submerged structures.
- Controlling sound scattering is crucial for applications requiring stealth or enhanced acoustic communication.
Purpose of the Study:
- To investigate the theoretical possibility of achieving acoustic invisibility for a flexible cylindrical shell in shallow water.
- To determine the conditions under which sound scattering and transmission can be minimized.
Main Methods:
- Acoustic and structural dynamics models were employed to analyze sound scattering.
- A Fourier transform was used for tangential and vertical directions, coupled with a collocation technique and orthogonalization for edge conditions.
Main Results:
- Zero sound scattering, indicative of acoustic invisibility, is theoretically attainable.
- A continuous oscillating pressure load on the shell's wall can achieve acoustic invisibility.
- Zero sound transmission into the shell's inner fluid is also achievable.
Conclusions:
- Acoustic invisibility is a feasible concept for flexible cylindrical shells in shallow water.
- The application of a precisely controlled oscillating pressure load is key to achieving this phenomenon.
- Further research can explore discrete pressure load distributions for practical applications.
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