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arXiv · 0805.1925

Shearing active gels close to the isotropic-nematic transition

M. E. Cates·S. M. Fielding·D. Marenduzzo·E. Orlandini·J. M. Yeomans
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Abstract

We study numerically the rheological properties of a slab of active gel close o the isotropic-nematic transition. The flow behavior shows strong dependence on sample size, boundary conditions, and on the bulk constitutive curve, which, on entering the nematic phase, acquires an activity-induced discontinuity at the origin. The precursor of this within the metastable isotropic phase for contractile systems ({\em e.g.,} actomyosin gels) gives a viscosity divergence; its counterpart for extensile ({\em e.g.,} {\em B. subtilis}) suspensions admits instead a shear-banded flow with zero apparent viscosity.

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M. E. Cates, S. M. Fielding, D. Marenduzzo, E. Orlandini, J. M. Yeomans. 2008-05-13. Shearing active gels close to the isotropic-nematic transition. https://doi.org/10.1103/physrevlett.101.068102

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