Guided acoustic waves at periodically structured edges: Linear modes and nonlinear generation of Lamb and surface waves
- Acoustic waves are investigated which are guided at the edge (apex line) of a wedge-shaped elastic body or at the edge of an elastic plate. The edges contain a periodic sequence of modifications, consisting either of indentations or inclusions with a different elastic material which gives rise to high acoustic mismatch. Dispersion relations are computed with the help of the finite element method.Acoustic waves are investigated which are guided at the edge (apex line) of a wedge-shaped elastic body or at the edge of an elastic plate. The edges contain a periodic sequence of modifications, consisting either of indentations or inclusions with a different elastic material which gives rise to high acoustic mismatch. Dispersion relations are computed with the help of the finite element method. They exhibit zero-group velocity points on the dispersion branches of edge-localized acoustic modes. These special points also occur at Bloch-Floquet wavenumbers away from the Brillouin zone boundary. Deep indentations lead to flat branches corresponding to largely non-interacting, Einstein-oscillator like vibrations of the tongues between the grooves of the periodic structure. Due to the nonlinearity of the elastic media, quantified by their third-order elastic constants, an acoustic mode localized at a periodically modified edge generates a second harmonic which partly consists of surface and plate modes propagating into the elastic medium in the direction vertical to the edge. This acoustic radiation at the second-harmonic frequency is investigated for an elastic plate and a truncated sharp-angle wedge with periodic inclusions at their edges. Unlike nonlinear bulk wave generation by surface acoustic waves in an interdigital structure, surface and plate mode radiation by edge-localized modes can be visualized directly in laser-ultrasound experiments.…
Document Type: | Article (reviewed) |
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Zitierlink: | https://opus.hs-offenburg.de/6618 | Bibliografische Angaben |
Title (English): | Guided acoustic waves at periodically structured edges: Linear modes and nonlinear generation of Lamb and surface waves |
Author: | Ilya Nedospasov, Pavel Dmitrievich PupyrevStaff MemberORCiDGND, Nikolaus BechlerGND, Jingxue Tham, Iren E. Kuznetsova, Andreas MayerStaff MemberGND |
Year of Publication: | 2022 |
Publisher: | Elsevier |
Page Number: | 13 |
Article Number: | 116854 |
Parent Title (English): | Journal of Sound and Vibration |
Volume: | 527 |
ISSN: | 0022-460X (Print) |
ISSN: | 1095-8568 (Online) |
DOI: | https://doi.org/10.1016/j.jsv.2022.116854 |
Language: | English | Inhaltliche Informationen |
Institutes: | Fakultät Maschinenbau und Verfahrenstechnik (M+V) |
Fakultät Wirtschaft (W) | |
Institutes: | Bibliografie |
Tag: | Edge waves; Finite element method; Nonlinearity; Phononic crystal; Wedge waves | Formale Angaben |
Relevance: | Wiss. Zeitschriftenartikel reviewed: Listung in Master Journal List |
Open Access: | Closed |
Licence (German): | Urheberrechtlich geschützt |