Skip to main content

Research Repository

Advanced Search

A Boundary Element Method (BEM) Solver for Low Frequency Room Modes

Cicero, Andrea; Hargreaves, Jonathan A.

A Boundary Element Method (BEM) Solver for Low Frequency Room Modes Thumbnail


Authors

Andrea Cicero



Abstract

Room modes are known to be problematic in small critical listening environments. They degrade the acoustic quality at low frequencies, producing peaks and nulls in the frequency domain and ringing in the time domain. The Finite Element Method (FEM) is currently the easiest way to predict such resonances for arbitrarily shaped rooms. This solves for mode frequencies and shapes, as well as Q-factors and decay rates. Such 'eigenfrequency' solvers are commonplace in FEM, but FEM has the disadvantage of needing to mesh the entire air volume in the room. The Boundary Element Method (BEM) avoids this and only requires a simple boundary mesh, but solution of its eigenfrequency problems is much more challenging and appears in only a few academic papers. Here we transfer those approaches to Room Acoustics. We implement the block Sakurai-Sugiura method, which uses a contour integral in the complex frequency plane to convert the BEM eigenfrequency problem, which is usually non-linear in wavenumber, into a standard linear eigenfrequency problem that is straightforward to solve. The method is demonstrated through application to a cuboid room and an irregularly shaped room, both with impedance boundary conditions. Results are validated against FEM and discussed.

Citation

Cicero, A., & Hargreaves, J. A. (2022, August). A Boundary Element Method (BEM) Solver for Low Frequency Room Modes. Presented at Internoise 2022, Glasgow, Scotland

Presentation Conference Type Other
Conference Name Internoise 2022
Conference Location Glasgow, Scotland
Start Date Aug 21, 2022
End Date Aug 24, 2022
Publication Date Aug 22, 2022
Deposit Date Oct 6, 2022
Publicly Available Date Mar 28, 2024
DOI https://doi.org/10.3397/in_2022_0347
Keywords Applied Mathematics, General Mathematics
Publisher URL https://internoise2022.org/
Additional Information Event Type : Conference

Files





You might also like



Downloadable Citations