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A method to calculate acoustic radiation modes based on spheroidal wave functions
Yiming Wang1, Yangfan Liu1, J Stuart Bolton1
1Ray W. Herrick Laboratories, School of Mechanical Engineering, Purdue University, 177 South Russell Street, West Lafayette, Indiana 47907-2099, USA wang1679@purdue.edu, yangfan@purdue.edu, bolton@purdue.edu.
JASA Express Letters
|September 26, 2022
Summary
This study introduces a more efficient method for calculating acoustic radiation modes (ARMs) using spheroidal harmonics. This approach offers improved computational speed for noise control engineering applications.
Area of Science:
- Acoustics and Noise Control Engineering
Background:
- Acoustic radiation modes (ARMs) are crucial for noise control.
- The boundary element method (BEM) is commonly used for ARM calculation but is computationally intensive for high frequencies and large structures.
- Previous alternative methods utilized generalized singular value decomposition and spherical harmonic functions.
Purpose of the Study:
- To propose a novel and more efficient method for calculating acoustic radiation modes (ARMs).
- To investigate the use of spheroidal harmonic functions as an alternative to spherical harmonic functions for ARM computation.
- To enhance computational efficiency for structures with specific dimensional characteristics.
Main Methods:
- Utilizing generalized singular value decomposition.
- Employing spheroidal harmonic functions instead of spherical harmonic functions.
- Applying the method to calculate ARMs for arbitrarily shaped radiators.
Main Results:
- The proposed method using spheroidal harmonic functions provides an alternative to BEM for ARM calculation.
- This approach demonstrates potential for increased computational efficiency.
- The efficiency gains are particularly noted for structures where one dimension is significantly larger than the other two.
Conclusions:
- Spheroidal harmonic functions offer a computationally efficient alternative for calculating ARMs.
- The developed method is advantageous for noise control engineering, especially for elongated structures.
- This research contributes to faster and more effective noise control solutions.
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