Efficient calculation of the three-dimensional sound pressure field around a slab track
Journal article, 2024

The wavenumber domain Boundary Element (2.5D BE) method is well suited to calculate the acoustic sound field around structures with a constant cross-section along one dimension, such as noise barriers or railway track. By expressing the sound field along this dimension in wavenumber domain, the numerical model is reduced from a 3D model to 2D model at each wavenumber. A consequence of the required discrete Fourier domain representation is that the sound field is represented by periodically repeating sections, of which only one section is physically meaningful. The resolution and the number of required wavenumbers increases with the desired length and spatial discretisation of this section. Describing the sound field adequately to auralise the sound without disturbing artefacts requires a large number of wavenumbers (and thus 2D BE computations), which is not feasible for large geometries. Here, a method is introduced that allows the calculation of the 3D sound field by solving a single 2D BE problem for a dense frequency spectrum and interpolating at higher wavenumbers. The calculation efficiency is further increased by precalculating the acoustic transfer functions between each BE surface element and receiver positions. Combining these two methods allows for efficient calculation of the 3D sound field around acoustically rigid structures such as slab tracks. The numerical approach is validated by comparison with a standard 2.5D BEM calculation and an analytical solution. Precalculated transfer functions to calculate the sound radiation from railway track, which are made available online, are illustrated. An example application is presented.

Acoustic sound field

2.5D BE

Railway track

Acoustic transfer functions

Numerical methods

Author

Jannik Theyssen

Chalmers, Architecture and Civil Engineering, Applied Acoustics

Astrid Pieringer

Chalmers, Architecture and Civil Engineering, Applied Acoustics

Wolfgang Kropp

Chalmers, Architecture and Civil Engineering, Applied Acoustics

Acta Acustica

10224793 (ISSN) 26814617 (eISSN)

Vol. 8 4

Driving research and innovation to push Europe's rail system forward (IN2TRACK3)

European Commission (EC) (EC/H2020/101012456), 2021-01-01 -- 2023-12-31.

Swedish Transport Administration (2021/19114), 2021-01-01 -- 2023-12-31.

Areas of Advance

Transport

Subject Categories

Applied Mechanics

Fluid Mechanics and Acoustics

DOI

10.1051/aacus/2023068

More information

Latest update

2/2/2024 1