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Updated: Jan 27, 2026
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Measuring Material Microstructure Under Flow Using 1-2 Plane Flow-Small Angle Neutron Scattering
Published on: February 6, 2014
14.8K
Bubbly flow velocity measurement in multiple scattering regime.
Olivier Lombard1, Lilian D'Hondt2, Matthieu Cavaro3
1Aix-Marseille Univ, CNRS (UPR 7051), Centrale Marseille, LMA, 13402 Marseille, France.
Ultrasonics
|March 22, 2019
Summary
We developed a new acoustic technique to measure bubble cloud velocity using coda correlation of scattered waves. This method accurately tracks particle flow, validated by optical measurements.
Area of Science:
- Acoustics
- Fluid Dynamics
- Wave Scattering
Background:
- Measuring particle flow velocity, such as bubble clouds, is crucial in various scientific and industrial applications.
- Traditional methods may face limitations in complex environments with multiple scattering effects.
Purpose of the Study:
- To introduce and validate a novel acoustic technique for measuring bubble cloud velocity.
- To establish the relationship between coda wave correlation and bubble cloud velocity using diffusion approximation.
Main Methods:
- Utilizing successive recordings of multiple scattered acoustic waves from a bubble cloud.
- Applying coda correlation analysis to predict bubble cloud velocity.
- Validating the acoustic method with simultaneous optical measurements in a controlled water tank environment.
Main Results:
- The proposed coda correlation technique accurately measures bubble cloud velocity.
- Experimental results showed good agreement with optical measurements, with a relative difference below 7%.
Conclusions:
- The developed acoustic technique provides a reliable method for measuring bubble cloud velocity.
- This technique is adaptable for various particle flow velocity measurements involving acoustic multiple scattering.
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