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arXiv · 1003.4895

Polymer rheology simulations at the meso- and macroscopic scale

Eric Sultan·Jan-Willem Van De Meent·Ellak Somfai·Alexander N. Morozov·Wim Van Saarloos
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Abstract

We show that simulations of polymer rheology at a fluctuating mesoscopic scale and at the macroscopic scale where flow instabilities occur can be achieved at the same time with dissipative particle dynamics (DPD) technique.} We model the visco-elasticity of polymer liquids by introducing a finite fraction of dumbbells in the standard DPD fluid. The stretching and tumbling statistics of these dumbbells is in agreement with what is known for isolated polymers in shear flows. At the same time, the model exhibits behaviour reminiscent of drag reduction in the turbulent state: as the polymer fraction increases, the onset of turbulence in plane Couette flow is pushed to higher Reynolds numbers. The method opens up the possibility to model nontrivial rheological conditions with ensuing coarse grained polymer statistics.

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Eric Sultan, Jan-Willem Van De Meent, Ellak Somfai, Alexander N. Morozov, Wim Van Saarloos. 2010-06-06. Polymer rheology simulations at the meso- and macroscopic scale. https://doi.org/10.1209/0295-5075%2F90%2F64002

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