Propagation of waves in nonlocal-periodic systems
| Autor: | Alexander Hvatov, Antonio Carcaterra, A.S. Rezaei, Federica Mezzani, Sergey Sorokin |
|---|---|
| Jazyk: | angličtina |
| Rok vydání: | 2021 |
| Předmět: |
Floquet theory
Acoustics and Ultrasonics Wave propagation graph theory Periodic structures periodic structures wave propagation long-range interactions floquet theory eigenfrequency analysis insertion losses graph theory 02 engineering and technology 01 natural sciences law.invention 0203 mechanical engineering law 0103 physical sciences insertion losses Dispersion (water waves) 010301 acoustics Physics Plane (geometry) Mechanical Engineering Mathematical analysis Condensed Matter Physics Eigenfrequency analysis Graph theory Long-range interactions 020303 mechanical engineering & transports Mechanics of Materials Frequency domain Group velocity Insertion losses Waveguide Longitudinal wave |
| Zdroj: | Rezaei, A S, Carcaterra, A, Sorokin, S, Hvatov, A & Mezzani, F 2021, ' Propagation of waves in nonlocal-periodic systems ', Journal of Sound and Vibration, vol. 506, 116156 . https://doi.org/10.1016/j.jsv.2021.116156 |
| DOI: | 10.1016/j.jsv.2021.116156 |
| Popis: | This paper is concerned with emergence of novel effects in wave propagation in one-dimensional waveguides, when integrated with periodic nonlocalities. The nonlocalities are introduced by a connectivity superimposed to a conventional waveguide and depicted as a graph with trees and leaves, each with its own periodicity. Merging nonlocality and periodicity notions induces a distinction between homogenous and non-homogenous periodic configurations. Specifically, various unconventional phenomena linked to the presence of nonlocalities result in disruption of the energy transmission in such systems, disclosing new opportunities for vibration isolation applications. To demonstrate these effects, simple models of propagation of plane extension/compression waves in a uniform infinite rod equipped with co-axial spring-like elements is used. The homogenous case is analysed by a direct double, space and time, Fourier transform, leading to discussion of unusual dispersion effects, including vanishing and negative group velocity. In the non-homogeneous case, the canonical Floquet theory is used to identify stopbands and control their positions in the frequency domain. The results are compared with eigenfrequency analysis of unit periodicity cells and finite structures. Next, the forcing problem is considered and the insertion losses in a semi-infinite rod with nonlocal spring effects are computed to corroborate predictions of Floquet theory, providing physical explanations of the obtained results. Finally, possibilities to employ the non-local interaction forces in an active control format to generate stopbands at arbitrarily low frequencies are highlighted. |
| Databáze: | OpenAIRE |
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