Acoustical Wave Propagation in Sonic Composites
Journal Title: Analele Universitatii "Eftimie Murgu" Resita. Fascicula de Inginerie - Year 2015, Vol 22, Issue 2
Abstract
The goal of this paper is to discuss the technique of controlling the mechanical properties of sonic composites. The idea is to architecture the scatterers and material from which they are made, their number and geometry in order to obtain special features in their response to external waves. We refer to perfectly reflecting of acoustical waves over a desired range of frequencies or to prohibit their propagation in certain directions, or confining the waves within specified volumes. The internal structure of the material has to be chosen in such a way that to avoid the scattering of acoustical waves inside the material. This is possible if certain band-gaps of frequencies can be generated for which the waves are forbidden to propagate in certain directions. These band-gaps can be extended to cover all possible directions of propagation by resulting a full band-gap. If the band-gaps are not wide enough, their frequency ranges do not overlap. These band-gaps can overlap due to reflections on the surface of thick scatterers, as well as due to wave propagation inside them. growth.
Authors and Affiliations
Iulian Girip, Ruxandra Diana Ilie
Keywords
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