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Showing 1 to 12 of 12 for “"Acoustic Metamaterial"”.
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Acoustic metamaterial design and applications
The explosion of interest in metamaterials is due to the dramatically increased manipulation ability over light as well as sound waves. This material research was stimulated by the opportunity to develop an artificial media with negative refractive index and the application in superlens which …
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An Investigation on Acoustic Metamaterial Physics to Inspire the Design of Novel Aircraft Engine Liners
… of quiet aircraft. This thesis investigates acoustic metamaterials and their ability to achieve superior transmission loss characteristics not found in traditional honeycomb liners. The acoustic metamaterials investigated are an array of Helmholtz resonators with and without coupled cavities …
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Investigation of defects on acoustic scattering in cloak by molding process
… was developed in order to replicate the acoustic cloak. The metal was cast into a stretchable PDMS mold, which was cast from micromachined aluminum cloak. For the PDMS mold, the mold release agent, trichlorosilane ([tridecafluoro-1,1,2,2-tetrahydrooctyl] trichlorosilane), was enhanced to …
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Acoustic Metamaterials at the Microscale
… ratio, or strength. However, dynamic and acoustic properties of micro-architected materials remain largely unexplored, partially because it is challenging to measure their response at these scales. Dispersion resulting from Bragg scattering occurs at wavelengths which are dictated by the …
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Wavefront Engineering and Computational Sensing with Acoustic Metamaterials
<p>Acoustic metamaterials are a family of engineered materials that can be designed to possess flexible acoustic properties. They are composed of subwavelength periodic structures that can be homogenized as effective materials within the designed frequency bands. Acoustic wave controlling devices …
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Design and Experimental Applications of Acoustic Metamaterials
<p>Acoustic metamaterials are engineered materials that were extensively investigated over the last years mainly because they promise properties otherwise hard or impossible to find in nature. Consequently, they open the door for improved or completely new applications (e.g. acoustic superlens that …
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Theoretical and experimental studies of the dynamics and acoustics of forced ordered granular networks
… exists there is complete absence of linear acoustics in ordered granular media, which results in zero speed of sound as defined in the sense of linear acoustics through the classical wave equation; thus, these media have been characterized as “sonic vacua”. However, various nonlinear waves …
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Acoustic metamaterials comprised of dead-end pores and black hole effect for low frequency sound absorption in linear and nonlinear regimes
The aim of this work is to design and test acoustic metamaterial absorbers particularly for mitigation of low frequency sound of high intensity. The absorbers designed are formed of a series of plates with a central perforation, separated by air cavities. Two types of structures are investigated: …
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Low Frequency Noise Reduction Using Novel Poro-Elastic Acoustic Metamaterials
… sound absorption and transmission loss using acoustic metamaterials. The acoustic metamaterials investigated consist of poro-elastic acoustic heterogeneous (HG) metamaterials and microperforated (MPP) acoustic metamaterials. HG metamaterials consist of poro-elastic material with a periodic …
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Turbulent Boundary Layers over Rough Surfaces: Large Structure Velocity Scaling and Driver Implications for Acoustic Metamaterials
Turbulent boundary layer and metamaterial properties were explored to initiate the viability of controlling acoustic waves driven by pressure fluctuations from flow. A turbulent boundary layer scaling analysis was performed on zero-pressure-gradient turbulent boundary layers over rough surfaces, …
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Strongly nonlinear dynamics and acoustics of coupled granular sonic vacua: theoretical and experimental studies
… of highly discontinuous and adaptive granular acoustic metamaterials for shock wave redirection and control are discussed. Then we focus on another class of granular acoustic metamaterials, namely, one-dimensional single or coupled granular chains embedded in elastic matrix, and present …