Transformational Acoustics Applied to Scattering from a Thin Elastic Shell.

摘要

We investigate the behavior of acoustic cloaks and design an acoustic cloak applied to a thin spherical shell. We begin by examining the acoustic pressure field scattered from a spherical object, consider limiting impedance situations for a homogeneous sphere, and a thin shell. The second part of this thesis is focused on acoustic cloaking theory. Our research in this area concentrated on the application of the transformational acoustics method as a solution to model and characterize physical parameters and fields involved in an acoustics cloak parameterization. A trade-off between an effective cloak and a possible realizable metamaterial dictates the characterization of the anisotropic inertia and stiffness parameters for the cloak design. Two limiting acoustic metafluids properties are explored. Lastly, we analyze the performance of the acoustic cloak when it is applied to scattering from a spherical shell.