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Incorporating source directionality into outdoor sound propagation calculations
Sergey N Vecherin1, D Keith Wilson, Vladimir E Ostashev
1United States Army Cold Regions Research and Engineering Laboratory, 72 Lyme Road, Hanover, New Hampshire 03755, USA. Sergey.N.Vecherin@usace.army.mil
The Journal of the Acoustical Society of America
|January 10, 2012
Summary
This study introduces two methods, equivalent source method (ESM) and directional starter method (DSM), to improve long-range sound propagation models for directional sources like aircraft. Both methods accurately predict sound directivity patterns.
Area of Science:
- Acoustics
- Environmental Science
- Engineering
Background:
- Outdoor sound sources like aircraft and vehicles have directional radiation patterns.
- Existing long-range sound propagation algorithms often assume omnidirectional point sources, limiting accuracy.
Purpose of the Study:
- To develop and compare methods for incorporating directional sound sources into long-range propagation algorithms.
- To enhance the accuracy of acoustic modeling for real-world sound sources.
Main Methods:
- Equivalent Source Method (ESM): Reconstructs a directional source using a distribution of omnidirectional point sources.
- Directional Starter Method (DSM): Specifically designed for parabolic equation (PE) algorithms, deriving directional starter fields without explicit source reconstruction.
Main Results:
- Both ESM and DSM successfully reproduce the directivity patterns of directional sound sources.
- DSM offers a simpler and potentially more convenient approach for PE algorithms, especially for limited azimuthal calculations.
Conclusions:
- The study presents effective methods for modeling directional sound sources in long-range acoustic propagation.
- DSM is a valuable alternative to ESM for PE-based acoustic modeling, offering computational advantages in specific scenarios.
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