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Acoustic scattering by a spherical obstacle: modification to the analytical long-wavelength solution for the
Valerie J Pinfield1, Richard E Challis
1Applied Ultrasonics Laboratory, Electrical Systems and Optics Division, Faculty of Engineering, University of Nottingham, Tower Building, University Park, Nottingham NG7 2RD, United Kingdom. valerie.pinfield@nottingham.ac.uk
The Journal of the Acoustical Society of America
|April 12, 2011
Summary
Approximate solutions for acoustic wave scattering by liquid particles differ from full solutions, impacting particle size estimates. Separating real and imaginary parts of a key coefficient improves approximation accuracy for acoustic wave scattering.
Area of Science:
- Acoustics
- Fluid Dynamics
- Materials Science
Background:
- Classical approximations for acoustic wave scattering by liquid particles in emulsions exhibit discrepancies with full solutions at specific low and high frequency ranges (k(c)a < 0.01 and k(c)a > 0.1).
- These discrepancies can lead to inaccuracies in estimating dispersed particle sizes using compression wave attenuation measurements.
Purpose of the Study:
- To explain the origin of differences between approximate and full solutions in acoustic wave scattering by liquid particles.
- To propose an improved approximation method for acoustic wave scattering calculations.
Main Methods:
- Analysis of classical long wavelength approximate solutions for acoustic wave scattering.
- Examination of the significance of terms within the modulus of the complex zero-order partial wave coefficient, A(0).
Main Results:
- Differences between approximate and full solutions arise from approximations in the modulus of the complex zero-order partial wave coefficient, A(0).
- The study identifies specific low and high frequency regimes where these differences are most pronounced.
Conclusions:
- A more accurate approximation for acoustic wave scattering can be achieved by considering the real and imaginary parts of the complex zero-order partial wave coefficient separately.
- This refined approach is crucial for improving the accuracy of dispersed particle size estimations based on acoustic attenuation.
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