A technique for measuring velocity and attenuation of ultrasound in liquid foams

TL;DR

This paper presents an experimental setup and inversion method for measuring ultrasonic velocity and attenuation in liquid foams across a broad frequency range, revealing sensitivity to foam bubble sizes.

Contribution

It introduces a novel experimental setup and inversion technique for ultrasonic property measurement in liquid foams, enabling potential foam characterization via spectroscopy.

Findings

Ultrasonic velocity and attenuation are highly sensitive to foam bubble sizes.

The proposed method successfully measures ultrasonic properties during foam coarsening.

Spectroscopy could be developed for liquid foam analysis.

Abstract

We describe an experimental setup specifically designed for measuring the ultrasonic transmission through liquid foams, over a broad range of frequencies (60-600 kHz). The question of determining the ultrasonic properties of the foam (density, phase velocity and attenuation) from the transmission measurements is addressed. An inversion method is proposed, tested on synthetic data, and applied to a liquid foam at different times during the coarsening. The ultrasonic velocity and attenuation are found to be very sensitive to the foam bubble sizes, suggesting that a spectroscopy technique could be developed for liquid foams.