Wall-anchored semiflexible polymer under large amplitude oscillatory shear flow

Antonio Lamura; Roland G. Winkler; Gerhard Gompper

doi:10.1063/5.0051427

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arXiv · 2112.05968

Wall-anchored semiflexible polymer under large amplitude oscillatory shear flow

Antonio Lamura·Roland G. Winkler·Gerhard Gompper

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Abstract

The properties of semiflexible polymers tethered by one end to an impenetrable wall and exposed to oscillatory shear flow are investigated by mesoscale simulations. A polymer, confined in two dimensions, is described by a linear bead-spring chain, and fluid interactions are incorporated by the Brownian multiparticle collision dynamics approach. At small strains, the polymers follow the applied flow field. However, at high strain, we find a strongly nonlinear response, with major conformational changes. Polymers are stretched along the flow direction and exhibit U-shaped conformations while following the flow. As a consequence of confinement in the half-space, a frequency doubling in the time-dependent polymer properties appears along the direction normal to the wall.

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Antonio Lamura, Roland G. Winkler, Gerhard Gompper. 2021-12-11. Wall-anchored semiflexible polymer under large amplitude oscillatory shear flow. https://doi.org/10.1063/5.0051427

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