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Acoustic scattering from a fluid cylinder with Willis constitutive properties.

ABSTRACT: A material that exhibits Willis coupling has constitutive equations that couple the pressure-strain and momentum-velocity relationships. This coupling arises from subwavelength asymmetry and non-locality in heterogeneous media. This paper considers the problem of the scattering of a plane wave by a cylinder exhibiting Willis coupling using both analytical and numerical approaches. First, a perturbation method is used to describe the influence of Willis coupling on the scattered field to a first-order approximation. A higher order analysis of the scattering based on generalized impedances is then derived. Finally, a finite-element method-based numerical scheme for calculating the scattered field is presented. These three analyses are compared and show strong agreement for low to moderate levels of Willis coupling.

SUBMITTER: Muhlestein MB

PROVIDER: S-EPMC6304021 | biostudies-literature | 2018 Dec

REPOSITORIES: biostudies-literature

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Acoustic scattering from a fluid cylinder with Willis constitutive properties.

Muhlestein Michael B MB Goldsberry Benjamin M BM Norris Andrew N AN Haberman Michael R MR

Proceedings. Mathematical, physical, and engineering sciences 20181212 2220

A material that exhibits Willis coupling has constitutive equations that couple the pressure-strain and momentum-velocity relationships. This coupling arises from subwavelength asymmetry and non-locality in heterogeneous media. This paper considers the problem of the scattering of a plane wave by a cylinder exhibiting Willis coupling using both analytical and numerical approaches. First, a perturbation method is used to describe the influence of Willis coupling on the scattered field to a first- ...[more]

PMID: 30602938

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