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Velocity Profiles in Slowly Sheared Bubble Rafts

John Lauridsen·Greg Chanan·Michael Dennin
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Abstract

Measurements of average velocity profiles in a bubble raft subjected to slow, steady-shear demonstrate the coexistence between a flowing state and a jammed state similar to that observed for three-dimensional foams and emulsions [Coussot {\it et al,}, Phys. Rev. Lett. {\bf 88}, 218301 (2002)]. For sufficiently slow shear, the flow is generated by nonlinear topological rearrangements. We report on the connection between this short-time motion of the bubbles and the long-time averages. We find that velocity profiles for individual rearrangement events fluctuate, but a smooth, average velocity is reached after averaging over only a relatively few events.

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John Lauridsen, Greg Chanan, Michael Dennin. 2003-12-05. Velocity Profiles in Slowly Sheared Bubble Rafts. https://doi.org/10.1103/physrevlett.93.018303

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