Calculated wind noise for an infrasonic wind noise enclosure
JohnPaul Abbott1, Richard Raspet1
1Department of Physics and Astronomy and National Center for Physical Acoustics, The University of Mississippi, P.O. Box 1848, 145 Hill Drive, University, Mississippi 38677, USA.
The Journal of the Acoustical Society of America
|August 3, 2015
Summary
A new model accurately predicts wind noise inside porous enclosures by combining internal and external turbulence interactions. This calculation method offers a ±5 dB agreement with measured wind noise, improving acoustic predictions.
Area of Science:
- Acoustics
- Fluid Dynamics
- Environmental Engineering
Background:
- Wind noise in porous structures poses challenges for acoustic monitoring.
- Understanding noise generation mechanisms is crucial for mitigation strategies.
Purpose of the Study:
- To develop a simple calculation model for wind noise at the center of a large porous wind fence enclosure.
- To accurately predict wind noise by accounting for various turbulence interactions.
Main Methods:
- Combining wind noise contributions from internal turbulence-turbulence, turbulence-shear interactions, surface turbulence interactions, and external turbulence-shear interactions.
- Utilizing measured turbulence spectra, velocity profiles, correlation lengths, and mean velocities.
- Verifying the model by comparing calculated estimates with measured wind noise.
Main Results:
- The developed calculation model shows good agreement with measured wind noise, within ±5 dB.
- The model successfully quantifies contributions from different interaction types.
- Verification confirmed the model's predictive capability.
Conclusions:
- A simplified calculation model effectively predicts wind noise in porous enclosures.
- The model's accuracy validates the approach of combining diverse turbulence interaction contributions.
- This method enhances the understanding and prediction of acoustic environments within such structures.
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