Slip, concentration fluctuations and flow instability in sheared polymer solutions

William B. Black; Michael D. Graham

doi:10.1021/ma0107455

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arXiv · cond-mat/0101356

Slip, concentration fluctuations and flow instability in sheared polymer solutions

William B. Black·Michael D. Graham

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Abstract

Recent experiments suggest that shear-enhanced growth of concentration fluctuations in polymer solutions is strongly influenced by solid boundaries. We analyze the dynamics of a model of a sheared polymer solution, accounting for the effect of stress variations on mass flux and for wall-slip. If (and only if) these effects are present, the flow exhibits a boundary-localized instability consistent with experimental observations. Even in the absence of flow instability, thermally-driven concentration fluctuations are significantly enhanced near the boundary.

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William B. Black, Michael D. Graham. 2001-01-23. Slip, concentration fluctuations and flow instability in sheared polymer solutions. https://doi.org/10.1021/ma0107455

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