We show that simulations of polymer rheology at a fluctuating mesoscopicscale and at the macroscopic scale where flow instabilities occur can beachieved at the same time with dissipative particle dynamics (DPD) technique.}We model the visco-elasticity of polymer liquids by introducing a finitefraction of dumbbells in the standard DPD fluid. The stretching and tumblingstatistics of these dumbbells is in agreement with what is known for isolatedpolymers in shear flows. At the same time, the model exhibits behaviourreminiscent of drag reduction in the turbulent state: as the polymer fractionincreases, the onset of turbulence in plane Couette flow is pushed to higherReynolds numbers. The method opens up the possibility to model nontrivialrheological conditions with ensuing coarse grained polymer statistics.
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