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Elastic Convection in Vibrated Viscoplastic Fluids

Hayato Shiba·Jori Ruppert-Felsot·Yoshiki Takahashi·Yoshihiro Murayama·Qi Ouyang·Masaki Sano
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Abstract

We observe a new type of behavior in a shear thinning yield stress fluid: freestanding convection rolls driven by vertical oscillation. The convection occurs without the constraint of container boundaries yet the diameter of the rolls is spontaneously selected for a wide range of parameters. The transition to the convecting state occurs without hysteresis when the amplitude of the plate acceleration exceeds a critical value. We find that a non-dimensional stress, the stress due to the inertia of the fluid normalized by the yield stress, governs the onset of the convective motion.

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Hayato Shiba, Jori Ruppert-Felsot, Yoshiki Takahashi, Yoshihiro Murayama, Qi Ouyang, Masaki Sano. 2006-08-07. Elastic Convection in Vibrated Viscoplastic Fluids. https://doi.org/10.1103/physrevlett.98.044501

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