One path to acoustic cloaking
Steven A. Cummer,David Schurig +1 more
Reads0
Chats0
TLDR
In this paper, it was shown that the acoustic equations in a fluid are identical in form to the single polarization Maxwell equations via a variable exchange that also preserves boundary conditions, and the existence of transformation-type solutions for the 2D acoustic equations with anisotropic mass via time harmonic simulations of acoustic cloaking.Abstract:
A complete analysis of coordinate transformations in elastic media by Milton et al has shown that, in general, the equations of motion are not form invariant and thus do not admit transformation-type solutions of the type discovered by Pendry et al for electromagnetics. However, in a two-dimensional (2D) geometry, the acoustic equations in a fluid are identical in form to the single polarization Maxwell equations via a variable exchange that also preserves boundary conditions. We confirm the existence of transformation-type solutions for the 2D acoustic equations with anisotropic mass via time harmonic simulations of acoustic cloaking. We discuss the possibilities of experimentally demonstrating acoustic cloaking and analyse why this special equivalence of acoustics and electromagnetics occurs only in 2D.read more
Citations
More filters
Journal ArticleDOI
Homogeneous material based acoustic concentrators and rotators with linear coordinate transformation.
TL;DR: In this paper, the authors report the design of acoustic concentrator and rotator facilitated by linear coordinate transformation, which can focus and rotate the acoustic field in a given region while keeping the outside region unchanged.
Transformational acoustics applied to scattering from a thin elastic shell
TL;DR: In this article, the authors investigated the behavior of acoustic cloaks and designed an acoustic cloak applied to a thin spherical shell, and analyzed the performance of the acoustic cloak when it is applied to scattering from a spherical shell.
Tailoring Acoustic Metamaterials to Aeroacoustic Applications
TL;DR: In this paper, the authors investigate the applicability of metamaterials in the aero-acoustic domain and present an original approach to extend the existing theory to the analysis of moving media and obstacles.
Journal ArticleDOI
Bi-objective topology optimization for direct current concentration and heat flux cloaking using adaptive weighting method
Proceedings ArticleDOI
Optimized cloaking design in moving fluid based on the scattering analysis method
Siyang Zhong,Xun Huang +1 more
TL;DR: In this paper, a theoretical framework was developed to analyze acoustic cloak's scattering in a moving environment and the equivalent sound source induced by the moving environment local to the cloak was constructed and estimated using Born approximation.
References
More filters
Journal ArticleDOI
Magnetism from conductors and enhanced nonlinear phenomena
TL;DR: In this paper, it was shown that microstructures built from nonmagnetic conducting sheets exhibit an effective magnetic permeability /spl mu/sub eff/, which can be tuned to values not accessible in naturally occurring materials.
Journal ArticleDOI
Controlling Electromagnetic Fields
TL;DR: This work shows how electromagnetic fields can be redirected at will and proposes a design strategy that has relevance to exotic lens design and to the cloaking of objects from electromagnetic fields.
Journal ArticleDOI
Metamaterial Electromagnetic Cloak at Microwave Frequencies
David Schurig,Jack J. Mock,B.J. Justice,Steven A. Cummer,John B. Pendry,Anthony F. Starr,David R. Smith +6 more
TL;DR: This work describes here the first practical realization of a cloak of invisibility, constructed with the use of artificially structured metamaterials, designed for operation over a band of microwave frequencies.
Journal ArticleDOI
Optical Conformal Mapping
TL;DR: A general recipe for the design of media that create perfect invisibility within the accuracy of geometrical optics is developed, which can be applied to escape detection by other electromagnetic waves or sound.
Journal ArticleDOI
Ultrasonic metamaterials with negative modulus
Nicholas X. Fang,Dongjuan Xi,Jianyi Xu,Muralidhar Ambati,Werayut Srituravanich,Cheng Sun,Xiang Zhang +6 more
TL;DR: A new class of ultrasonic metamaterials consisting of an array of subwavelength Helmholtz resonators with designed acoustic inductance and capacitance with an effective dynamic modulus with negative values near the resonance frequency is reported.