Computer modelling of coupled spaces: variations of eigenmodes frequency due to a change in coupling area

• Autorzy: Meissner M.
• Języki publikacji: EN

Abstrakty

EN

Acoustically coupled spaces have recently been drawing more and more attention in the architectural acoustics community, thus a determination of shapes and frequencies of eigenmodes in these room systems from computer-based models has become increasingly significant. In this investigation, an eigenvalue problem was solved numerically for a simple room system consisting of two connected rectangular spaces. In a numerical procedure, the forced oscillator method with a finite difference algorithm was applied. In order to determine the influence of irregularity of system shape on eigenmodes frequency, a modal behaviour in the coupled spaces was studied for several sizes of coupling area. Calculation results have shown that with the exception of a fundamental mode, the changes in resonant frequencies were relatively small. However, an increase in a system irregularity led to a coincidence of frequencies of neighbouring modes and variations in a sequence of modes on a frequency axis, which both contributed to a degeneration of eigenmodes.

Słowa kluczowe

EN

coupled spaces; modal analysis; degenerate modes; mode localization

• Wydawca: Instytut Podstawowych Problemów Techniki PAN ; Polska Akademia Nauk
• Czasopismo: Archives of Acoustics
• Rocznik: 2009
• Tom: Vol. 34, No. 2
• Strony: 157--168
• Opis fizyczny: Bibliogr 20 poz., rys., tab.

Twórcy

autor

Meissner M.

• Institute of Fundamental Technological Research, Polish Academy of Sciences, Pawińskiego 5b, 02-106 Warszawa, Poland,

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