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arXiv · 1503.05785

Three-dimensional foam flow resolved by fast X-ray tomographic microscopy

Christophe Raufaste·Benjamin Dollet·Kevin Mader·Stéphane Santucci·Rajmund Mokso
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Abstract

Thanks to ultra fast and high resolution X-ray tomography, we managed to capture the evolution of the local structure of the bubble network of a 3D foam flowing around a sphere. As for the 2D foam flow around a circular obstacle, we observed an axisymmetric velocity field with a recirculation zone, and indications of a negative wake downstream the obstacle. The bubble deformations, quantified by a shape tensor, are smaller than in 2D, due to a purely 3D feature: the azimuthal bubble shape variation. Moreover, we were able to detect plastic rearrangements, characterized by the neighbor-swapping of four bubbles. Their spatial structure suggest that rearrangements are triggered when films faces get smaller than a characteristic area.

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Christophe Raufaste, Benjamin Dollet, Kevin Mader, Stéphane Santucci, Rajmund Mokso. 2015-03-19. Three-dimensional foam flow resolved by fast X-ray tomographic microscopy. https://doi.org/10.1209/0295-5075/111/38004

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