Converging super-elliptic torsional shear waves in a bounded transverse isotropic viscoelastic material with nonhomogeneous outer boundary

• Main Authors: Caratelli, D. (Author), Guidetti, M. (Author), Royston, T.J (Author)
• Format: Article
• Language: English
• Published: Acoustical Society of America 2019
• Subjects: Elliptic coordinates; Isotropic property; Shear flow; Shear wave patterns; Shear waves; Theoretical approach; Torsional motion; Torsional shear; Transverse isotropic; Visco-elastic material; Viscoelasticity
• Online Access: View Fulltext in Publisher
• ISBN: 00014966 (ISSN)
• DOI: 10.1121/1.5134657

A theoretical approach was recently introduced [Guidetti and Royston, J. Acoust. Soc. Am. 144, 2312-2323 (2018)] for the radially converging slow shear wave pattern in transverse isotropic materials subjected to axisymmetric excitation normal to the axis of isotropy at the outer boundary of the material. This approach is enabled via transformation to an elliptic coordinate system with isotropic properties. The approach is extended to converging fast shear waves driven by axisymmetric torsional motion polarized in a plane containing the axis of isotropy. The approach involves transformation to a super-elliptic shape with isotropic properties and use of a numerically efficient boundary value approximation. © 2019 Acoustical Society of America.