Computational studies of steady-state sound field and reverberant sound decay in a system of two coupled rooms

• Authors: Mirosław Meissner
• Languages of publication: EN

Abstracts

EN

The acoustical properties of an irregularly shaped room consisting of two connected rectangular subrooms were studied. An eigenmode method supported by a numerical implementation has been used to predict acoustic characteristics of the coupled system, such as the distribution of the sound pressure in steady-state and the reverberation time. In the theoretical model a low-frequency limit was considered. In this case the eigenmodes are lightly damped, thusthey were approximated by normal acoustic modes of a hard-walled room. The eigenfunctions and eigenfrequencies were computed numerically via application of a forced oscillator method with a finite difference algorithm. The influence of coupling between subrooms on acoustic parameters of the enclosure was demonstrated in numerical simulations where different distributions of absorbing materials on the walls of the subrooms and various positions of the sound source were assumed. Calculation results have shown that for large differences in the absorption coefficient in the subrooms the effect of modal localization contributes to peaks of RMS pressure in steady-state and a large increase in the reverberation time.

Keywords

EN

Coupled rooms; modal analysis; reverberation time; modes localization

Discipline

• 43.20.+g: General linear acoustics
• 43.55.+p: Architectural acoustics

• Publisher: De Gruyter Open
• Journal: Open Physics
• Year: 2007
• Volume: 5
• Issue: 3
• Pages: 293-312

Dates

published

1 - 9 - 2007

online

12 - 4 - 2007

Contributors

author

Mirosław Meissner

• Institute of Fundamental Technological Research, Polish Academy of Sciences, PL-00-049, Warsaw, Poland

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Identifiers

DOI

10.2478/s11534-007-0016-7