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arXiv · 1109.5046

Geometric scaling of purely-elastic flow instabilities

J. Zilz·R. J. Poole·M. A. Alves·D. Bartolo·B. Levache·A. Lindner
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Abstract

We present a combined experimental, numerical and theoretical investigation of the geometric scaling of the onset of a purely-elastic flow instability in a serpentine channel. Good qualitative agreement is obtained between experiments, using dilute solutions of flexible polymers in microfluidic devices, and two-dimensional numerical simulations using the UCM model. The results are confirmed by a simple theoretical analysis, based on the dimensionless criterion proposed by Pakdel-McKinley for onset of a purely-elastic instability.

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J. Zilz, R. J. Poole, M. A. Alves, D. Bartolo, B. Levache, A. Lindner. 2011-09-23. Geometric scaling of purely-elastic flow instabilities. https://doi.org/10.1017/jfm.2012.411

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