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arXiv · 1110.4338

Banding, Excitability and Chaos in Active Nematic Suspensions

L. Giomi·L. Mahadevan·B. Chakraborty·M. F. Hagan
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Abstract

Motivated by the observation of highly unstable flowing states in suspensions of microtubules and kinesin, we analyze a model of mutually-propelled filaments suspended in a solvent. The system undergoes a mean-field isotropic-nematic transition for large enough filament concentrations when the nematic order parameter is allowed to vary in space and time. We analyze the model in two contexts: a quasi-one-dimensional channel with no-slip walls and a two-dimensional box with periodic boundaries. Using stability analysis and numerical calculations we show that the interplay between non-uniform nematic order, activity, and flow results in a variety of complex scenarios that include spontaneous banded laminar flow, relaxation oscillations, and chaos.

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L. Giomi, L. Mahadevan, B. Chakraborty, M. F. Hagan. 2011-10-19. Banding, Excitability and Chaos in Active Nematic Suspensions. https://doi.org/10.1088/0951-7715%2F25%2F8%2F2245

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