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Fabrication and Operation of Acoustofluidic Devices Supporting Bulk Acoustic Standing Waves for Sheathless Focusing of Particles
Published on: March 6, 2016
Broadband cylindrical acoustic cloak for linear surface waves in a fluid
M Farhat1, S Enoch, S Guenneau
1Institut Fresnel, CNRS, Aix-Marseille Université, Campus Universitaire de Saint-Jérôme, 13013 Marseille, France.
Physical Review Letters
|October 15, 2008
Summary
Researchers created a cylindrical cloak that guides surface liquid waves around an object. This metamaterial cloaks acoustic sources by reducing wave scattering, demonstrating a novel application in wave manipulation.
Area of Science:
- Acoustics
- Metamaterials
- Fluid Dynamics
Background:
- Surface liquid waves are crucial in various physical phenomena.
- Controlling wave propagation is a significant challenge in acoustics and fluid dynamics.
- Metamaterials offer unique properties for manipulating wave phenomena.
Purpose of the Study:
- To practically realize a cylindrical cloak for linear surface liquid waves.
- To demonstrate the cloaking mechanism using homogenization theory and numerical simulations.
- To experimentally verify the cloak's effectiveness in reducing wave backscattering.
Main Methods:
- Theoretical demonstration using homogenization theory.
- Development of a structured metamaterial cloak.
- Numerical simulations for validating the homogenized cloak model.
- Experimental analysis of wave scattering with a low-viscosity fluid.
Main Results:
- The cloak effectively bends surface waves around a cylindrical obstacle.
- Homogenization theory reveals the cloak acts as an effective anisotropic fluid.
- Numerical simulations confirm the homogenized cloak's behavior matches the structured cloak.
- Experimental tests show decreased backscattering from the cloaked obstacle.
Conclusions:
- The first practical cylindrical cloak for surface liquid waves has been achieved.
- The cloak operates by creating an effective anisotropic fluid with low azimuthal viscosity.
- The study validates the theoretical model and demonstrates experimental effectiveness in reducing wave scattering.
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