Time‐resolved ultrasonic spectroscopy for bubbles

Abstract

We show that ultrasound can provide time‐resolved measurements of the size distribution and the concentration of bubbles in a liquid. The potential of the technique is demonstrated by following disappearance of bubbles having an average radius of 20 μm with a 10 ms time resolution. We show that our technique can detect small concentrations of bubbles, with a large spectrum of accessible bubble radii (from 80 nm to 40 μm for a gas volume fraction of ), and with a sub‐millisecond time resolution. This new technique could be a valuable tool for investigating rapid processes such as nucleation or dissolution of bubbles. © 2017 American Institute of Chemical Engineers AIChE J, 63: 4666–4672, 2017

Particle elastic modulus analysis of waterborne polyurethane nanoparticles by ultrasound scattering method

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Relation between quadrupole ultrasonic resonance and shear viscoelasticity of polymer droplets with different glass transition temperatures

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Detailed characterization of aeration in lubricating oils by an ultrasonic approach

“…In this work, we use the ISA to extract information on the bubbles from the 5 MHz transmission measurements. Details on the model and how to use it for monitoring a bubble population can be found in [15]. Therefore, we only give here an overview of the procedure.…”

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