The effect of evanescent modes on low-frequency sound field in rectangular rooms

• Autorzy: Meissner Mirosław

Identyfikatory

DOI

10.21008/j.0860-6897.2023.2.05

• Języki publikacji: EN

Abstrakty

EN

The paper investigates the sound field excited by a boundary pure-tone source in rigid-walled rectangular rooms. This approach is applicable in the low-frequency range, where sound absorption by wall surfaces can be considered negligible. The sound pressure was theoretically determined by applying the Green's function based on the cut-on and evanescent modes expansion instead of the usual normal mode expansion. The theoretical model was used to predict the spatial distribution of the sound pressure level at different source frequencies. The calculation results have shown that for audible frequencies below the cut-off frequency, the plane wave mode and evanescent modes strongly interfere which results in an interference pattern with large dips in the pressure level forming a continuous curve. A shape of this curve is highly dependent on the excitation frequency. These dips have been found to occur when the sound associated with the plane wave mode is cancelled by the sound produced by evanescent modes.

Słowa kluczowe

EN

rectangular room; evanescent modes; plane wave mode; sound cancellation; sound intensity

PL

pomieszczenie prostokątne; mody zanikające; tłumienie dźwięków; natężenie dźwięku

• Wydawca: Poznan University of Technology. Institute of Applied Mechanics
• Czasopismo: Vibrations in Physical Systems
• Rocznik: 2023
• Tom: Vol. 34, nr 2
• Strony: art. no. 2023205
• Opis fizyczny: Bibliogr. 12 poz., 1 rys., wykr.

Twórcy

autor

Meissner Mirosław

• Institute of Fundamental Technological Research, Polish Academy of Sciences, Pawińskiego 5B, 02-106 Warsaw

• https://orcid.org/0000-0003-3885-0273

Bibliografia

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• 12. M. Meissner; Spectral characteristics and localization of modes in acoustically coupled enclosures; Acta. Acoust. United Acust., 2009, 95(2), 300-305; DOI: 10.3813/AAA.918152

Uwagi

Opracowanie rekordu ze środków MNiSW, umowa nr SONP/SP/546092/2022 w ramach programu "Społeczna odpowiedzialność nauki" - moduł: Popularyzacja nauki i promocja sportu (2024).