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Sound source identification and sound radiation modeling in a moving medium using the time-domain equivalent source
Xiao-Zheng Zhang1, Chuan-Xing Bi1, Yong-Bin Zhang1
1Institute of Sound and Vibration Research, Hefei University of Technology, 193 Tunxi Road, Hefei 230009, People's Republic of China.
The Journal of the Acoustical Society of America
|May 22, 2015
Summary
A new time-domain equivalent source method accurately identifies sound sources in moving media by overcoming convection effects. This approach enables precise sound source identification and radiation modeling in both static and dynamic environments.
Area of Science:
- Acoustics
- Fluid Dynamics
- Signal Processing
Background:
- Planar near-field acoustic holography can reconstruct sound fields in moving media.
- Reconstructed fields in moving media are affected by convection, hindering accurate sound source identification.
Purpose of the Study:
- To develop a novel method for accurate sound source identification in moving media.
- To enable reliable sound radiation modeling in both moving and static media.
Main Methods:
- A time-domain equivalent source method is proposed, replacing real sources with time-domain equivalent sources.
- Iterative solving of equivalent source strengths utilizes measured pressure and convective time-domain Green's function.
- Time averaging is employed to mitigate instability during the iterative solving process.
Main Results:
- The solved equivalent source strengths are independent of convection effects.
- Numerical simulations demonstrate the method's robustness against noise.
- Time averaging effectively reduces iterative process instability.
Conclusions:
- The developed method accurately identifies sound sources in moving media.
- The method is suitable for sound radiation modeling in both moving and static media.
- This approach overcomes limitations of traditional acoustic holography in convective environments.
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