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07:14
A Method to Study Adaptation to Left-Right Reversed Audition
Published on: October 29, 2018
Inversion of spinning sound fields
1Department of Mechanical Engineering, University of Bath, Bath, England. m.j.carley@bath.ac.uk
The Journal of the Acoustical Society of America
|February 12, 2009
Summary
This study introduces a novel method for reconstructing rotating monopole sound sources using sideline acoustic pressure measurements. The technique accurately identifies sound source distributions, crucial for noise control in systems like ducted rotors and cooling fans.
Area of Science:
- Acoustics
- Aeroacoustics
- Noise Control Engineering
Background:
- Identifying and characterizing rotating sound sources is essential for effective noise reduction in various engineering applications.
- Existing methods often require extensive source information or struggle with complex acoustic fields.
- Understanding the acoustic radiation from rotating machinery is critical for designing quieter systems.
Purpose of the Study:
- To develop a robust method for reconstructing rotating monopole source distributions from sideline acoustic measurements.
- To enable accurate source identification without prior assumptions about the source characteristics.
- To validate the method's effectiveness on simulated data from relevant engineering applications.
Main Methods:
- A two-stage reconstruction process involving an intermediate line source derived from acoustic pressures.
- Decomposition of acoustic fields into circumferential modes to handle multiple azimuthal modes.
- Derivation of a far-field radiation integral form to establish reconstruction limits.
Main Results:
- Successful reconstruction of rotating monopole source distributions using sideline acoustic data.
- Demonstrated capability to handle single and multiple azimuthal modes through sequential application.
- Validation with simulated data from a ducted rotor system and an automotive cooling fan.
Conclusions:
- The presented method offers a reliable approach for rotating sound source reconstruction.
- It provides valuable insights for noise source identification and control in rotating machinery.
- The method's effectiveness is confirmed for practical applications in aeroacoustics and fan noise.
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