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arXiv · 1006.4485

Migration of semiflexible polymers in microcapillary flow

Raghunath Chelakkot·Roland. G. Winkler·Gerhard Gompper
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Abstract

The non-equilibrium structural and dynamical properties of a semiflexible polymer confined in a cylindrical microchannel and exposed to a Poiseuille flow is studied by mesoscale hydrodynamic simulations. For a polymer with a length half of its persistence length, large variations in orientation and conformations are found as a function of radial distance and flow strength. In particular, the polymer exhibits U-shaped conformations near the channel center. Hydrodynamic interactions lead to strong cross-streamline migration. Outward migration is governed by the polymer orientation and the corresponding anisotropy in its diffusivity. Strong tumbling motion is observed, with a tumbling time which exhibits the same dependence on Peclet number as a polymer in shear flow.

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Raghunath Chelakkot, Roland. G. Winkler, Gerhard Gompper. 2010-06-23. Migration of semiflexible polymers in microcapillary flow. https://doi.org/10.1209/0295-5075%2F91%2F14001

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