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Subcritical finite-amplitude solutions in plane Couette flow of visco-elastic fluids

Alexander N. Morozov·Wim van Saarloos
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Abstract

Plane Couette flow of visco-elastic fluids is shown to exhibit a purely elastic subcritical instability in spite of being linearly stable. The mechanism of this instability is proposed and the nonlinear stability analysis of plane Couette flow of the Upper-Convected Maxwell fluid is presented. It is found that above the critical Weissenberg number, a small finite-size perturbation is sufficient to create a secondary flow, and the threshold value for the amplitude of the perturbation decreases as the Weissenberg number increases. The results suggest a scenario for weakly turbulent visco-elastic flow which is similar to the one for Newtonian fluids as a function of Reynolds number.

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Alexander N. Morozov, Wim van Saarloos. 2004-11-10. Subcritical finite-amplitude solutions in plane Couette flow of visco-elastic fluids. https://arxiv.org/abs/cond-mat/0411243

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