To investigate the mechanism of wave trapping, acoustic embedded trapped modes associated with two-resonant-mode interference in two-dimensional duct–cavity structures are calculated by the feedback-loop closure principle, which allows us to analyze the traveling modes that construct the trapped modes. The exact two coexisting resonant modes that underpin an embedded trapped mode in a cavity open to two semi-infinite ducts are numerically demonstrated. At the interface between the cavity segment and a duct, total reflection can occur for a particular combination of two propagative guided waves in the cavity. With a particular cavity length and a particular frequency, total reflection also happens for the two reflected waves at the opposite end of the cavity. In this way, the two coexisting standing waves underpin a trapped mode. It is found that the two standing waves are not two closed-cavity modes. Thus, this work presents a new understanding of such embedded trapped modes as a product of total reflection of two guided waves at the interface between two waveguides, rather than interference between two eigenmodes of a closed cavity. Such total reflection of multiple guide modes is a result of mutual cancellation in transmission to the propagative channel(s) of the ducts. Thus, trapped modes involving more than two standing waves may occur at higher frequencies where more traveling modes in the ducts are propagative. For quasi-trapped modes, the Fano scattering phenomenon owing to the effects of two acoustic channels is also shown.


    Zugriff

    Zugriff prüfen

    Verfügbarkeit in meiner Bibliothek prüfen

    Bestellung bei Subito €


    Exportieren, teilen und zitieren



    Titel :

    Total Reflection of Two Guided Waves for Embedded Trapped Modes


    Beteiligte:
    Dai, Xiwen (Autor:in)

    Erschienen in:

    AIAA Journal ; 59 , 1 ; 131-139


    Erscheinungsdatum :

    2020-10-20


    Format / Umfang :

    9 pages




    Medientyp :

    Aufsatz (Zeitschrift)


    Format :

    Elektronische Ressource


    Sprache :

    Englisch




    Optical sensors utilizing resonant modes in total reflection structures

    Nelson, R.L. / Haus, J.W. / Birchfield, B. et al. | IEEE | 2004


    Optical Sensors Utilizing Resonant Modes in Total Reflection Structures

    Lasers and Electro-optics Society (Institute of Electrical and Electronics Engineers) | British Library Conference Proceedings | 2004


    Trapped Modes at Acoustically Rigid Splices

    Bi, WenPing / Pagneux, Vincent / Lafarge, Denis et al. | AIAA | 2009



    Guided Waves

    British Library Online Contents | 1995