Curtin University Homepage
  • Library
  • Help
    • Admin

    espace - Curtin’s institutional repository

    JavaScript is disabled for your browser. Some features of this site may not work without it.
    View Item 
    • espace Home
    • espace
    • Curtin Research Publications
    • View Item
    • espace Home
    • espace
    • Curtin Research Publications
    • View Item

    Wave propagation and attenuation in an infinite periodic structure of asymmetric scatterers

    Access Status
    Fulltext not available
    Authors
    McMahon, Darryl
    Date
    2017
    Type
    Conference Paper
    
    Metadata
    Show full item record
    Citation
    McMahon, D. 2017. Wave propagation and attenuation in an infinite periodic structure of asymmetric scatterers, in Proceedings of the 24th International Congress on Sound and Vibration 2017 (ICSV 24), Jul 23-27 2017, pp. 1836-1843. London, UK: International Institute of Acoustics and Vibration (IIAV).
    Source Title
    IIAV archives & Curran Associates
    Source Conference
    24th International Congress on Sound and Vibration 2017 (ICSV 2017)
    Faculty
    Faculty of Science and Engineering
    School
    School of Earth and Planetary Sciences (EPS)
    URI
    http://hdl.handle.net/20.500.11937/80740
    Collection
    • Curtin Research Publications
    Abstract

    Periodic structures exhibit interesting periodic structure wave (PSW) phenomena although the literature is mostly devoted to symmetric rather than asymmetric systems. Waves in asymmetric structures is a topic of interest for applications where the energy flow needs to be reduced in particular directions. Relatively little has been investigated about wave modes in asymmetric periodic structures that exhibit nonreciprocal wave propagation and attenuation. This paper reports on such an investigation but restricted to an infinite one-dimensional structure of equally spaced nonreciprocal scatterers of structure waves (SW). An infinite structure without boundary effects has wave characteristics the same between every pair (i.e. "cell") of adjacent scatterers, which simplifies the theory to considering only two adjacent cells. It is found that only one type of wave mode, an incoherent energy wave (IEW), can exist in an infinite nonreciprocal periodic structure. In the case of elastic scattering the IEW is a "passing" band in one direction and a "stopping" band in the opposite direction. The IEW is also an allowed mode for symmetric scatterers. However for symmetric scatterers three other modes are also possible for both directions. One is the well-known Bloch-Floquet wave (BFW), which for elastic scattering alternates between passing and stopping bands as a function of wavenumber. The other two "non-BFW" modes result from symmetric moduli of the reflection and transmission scattering coefficients, but asymmetric scattering phase shifts. In the case of elastic scattering one non-BFW is a passing band and the other is a stopping band. In contrast to BFW resulting from multiple reflections and transmissions of a single SW, the IEW and two non-BFW wave modes require two different but correlated SW coupled by scattering.

    Related items

    Showing items related by title, author, creator and subject.

    • Transmission, reflection and energy exchanges for waves in finite one-dimensional PT-symmetric periodic structures
      McMahon, Darryl (2019)
      Time reversibility of waves within a periodic structure constrains their properties but allows both elastic and inelastic scattering. Time reversible elastic scattering leads to Bloch-Floquet waves (BFW) exhibiting passing ...
    • Wave propagation in infinite periodic structures taking into account energy absorption
      McMahon, Darryl (2015)
      This paper explores the possibility of generalised periodic structure waves (PSW) that include the well-known Bloch-Floquet (BF) waves as a special case. We consider two types of structure waves (SW) in an infinite, ...
    • Coherent waves in finite, asymmetric, one dimensional periodic structures
      McMahon, Darryl (2018)
      The wave properties for a one dimensional periodic structure are related to the eigenvalues and eigenvectors of two pairs of 2x2 matrices M and N, E and G. M is the complex scattering matrix of coherent waves by a single ...
    Advanced search

    Browse

    Communities & CollectionsIssue DateAuthorTitleSubjectDocument TypeThis CollectionIssue DateAuthorTitleSubjectDocument Type

    My Account

    Admin

    Statistics

    Most Popular ItemsStatistics by CountryMost Popular Authors

    Follow Curtin

    • 
    • 
    • 
    • 
    • 

    CRICOS Provider Code: 00301JABN: 99 143 842 569TEQSA: PRV12158

    Copyright | Disclaimer | Privacy statement | Accessibility

    Curtin would like to pay respect to the Aboriginal and Torres Strait Islander members of our community by acknowledging the traditional owners of the land on which the Perth campus is located, the Whadjuk people of the Nyungar Nation; and on our Kalgoorlie campus, the Wongutha people of the North-Eastern Goldfields.