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Updated: Jan 15, 2026
13:02
Three-dimensional Particle Tracking Velocimetry for Turbulence Applications: Case of a Jet Flow
Published on: February 27, 2016
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Angle-of-arrival fluctuations in a turbulent atmosphere.
Vladimir E Ostashev1, Michael B Muhlestein1, D Keith Wilson1
1U.S. Army Engineer Research and Development Center, 72 Lyme Road, Hanover, New Hampshire 03755, USA.
The Journal of the Acoustical Society of America
|October 8, 2025
Summary
Atmospheric turbulence distorts sound wave angle-of-arrival (AOA), impacting sensor array performance. This study quantifies AOA fluctuation variance, finding it increases with turbulence intensity.
Area of Science:
- Acoustics
- Atmospheric Physics
- Signal Processing
Background:
- Atmospheric turbulence causes angle-of-arrival (AOA) fluctuations in sound waves.
- These fluctuations degrade the performance of sensor arrays for source detection, localization, and identification.
Purpose of the Study:
- To theoretically analyze the variance of AOA fluctuations measured by two microphones.
- To express AOA variance in terms of propagation parameters and turbulence characteristics.
Main Methods:
- Developed a theoretical model for AOA variance.
- Utilized von Kármán and Kolmogorov spectral models for atmospheric turbulence.
- Numerically studied the standard deviation of AOA fluctuations under typical atmospheric conditions.
Main Results:
- AOA variance depends on propagation range, microphone separation, acoustic frequency, and turbulence spectrum.
- Using the Kolmogorov model, variance simplifies to depend on the path-averaged structure-function parameter.
- The standard deviation of AOA fluctuations ranges from fractions of a degree to 1°-2°.
Conclusions:
- AOA fluctuation standard deviation increases with friction velocity and surface heat flux.
- The findings provide insights into sound propagation effects in the atmospheric boundary layer.
- This research is crucial for improving acoustic sensor array performance in turbulent environments.
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