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Liquid foams are assemblies of bubbles inside a continuous liquid
phase. The liquid is mostly confined inside microchannels, called
Plateau borders, found at the contact between three bubbles. These
liquid channels are sustained by capillary forces at the liquid-gas
interfaces, are not sensitive to the Plateau-Rayleigh instability, but
are flexible and deformable. When a foam is subjected to stresses the
liquid inside the channels might reorganize. A specific setup was
devoted to create one single liquid channel and to study its
spatio-temporal dynamics to mechanical forcing. This includes
drop-injected, bubble-burst or forced oscillations experiments. We
could show that the dynamics is driven by capillarity and this latter
is strong enough to trigger inertial flows even at the sub-millimetric
scale of the channels. Interesting flow geometries and features are
observed.
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