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arXiv · 1103.3567

Tumbling of polymers in semidilute solution under shear flow

C. -C. Huang·G. Sutmann·G. Gompper·R. G. Winkler
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Abstract

The tumbling dynamics of individual polymers in semidilute solution is studied by large-scale non-equilibrium mesoscale hydrodynamic simulations. We find that the tumbling time is equal to the non-equilibrium relaxation time of the polymer end-to-end distance along the flow direction and strongly depends on concentration. In addition, the normalized tumbling frequency as well as the widths of the alignment distribution functions for a given concentration-dependent Weissenberg number exhibit a weak concentration dependence in the cross-over regime from a dilute to a semidilute solution. For semidilute solutions a universal behavior is obtained. This is a consequence of screening of hydrodynamic interactions at polymer concentrations exceeding the overlap concentration.

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C. -C. Huang, G. Sutmann, G. Gompper, R. G. Winkler. 2011-03-18. Tumbling of polymers in semidilute solution under shear flow. https://doi.org/10.1209/0295-5075%2F93%2F54004

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