Rheology of active suspensions with hydrodynamic interactions

M. Moradi

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arXiv · 1701.08691

Rheology of active suspensions with hydrodynamic interactions

M. Moradi

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Abstract

Using a simple model of self-propelled particle, the effective shear viscosity of a dilute, spatially homogeneous suspension of active particles is studied. We use formulation of non-linear Fokker-Planck equation to drive a kinetic description, including the effect of external flow field, rotary diffusion, and particle-particle hydrodynamic interactions in two dimensions. Analytical expressions are obtained for the stress tensor at small Peclet numbers, in a simple shear flow, up to second order of volume fraction of the swimmers, which shows the explicit dependence of shear viscosity on the details of the swimming mechanism.

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M. Moradi. 2017-01-30. Rheology of active suspensions with hydrodynamic interactions. https://arxiv.org/abs/1701.08691

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