Thin film models for active gels

Abstract

In this study we present a free-boundary problem for an active liquid crystal based on the Beris-Edwards theory that uses a tensorial order parameter and includes active contributions to the stress tensor to analyse the rich defect structure observed in applications such as the Adenosinetriphosphate (ATP) driven motion of a thin film of an actin filament network. The small aspect ratio of the film geometry allows for an asymptotic approximation of the free-boundary problem in the limit of weak elasticity of the network and strong active terms. The new thin film model captures the defect dynamcs in the bulk as well as wall defects and thus presents a significant extension of previous models based on the Lesli-Erickson-Parodi theory. Analytic expression are derived that reveal the interplay of anchoring conditions, film thickness and active terms and their control of transitions of flow structure.

33 pages, 3 figures

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Cited by in corpus (5)

• Onsager's variational principle in active soft matter
• Thin-Film Modelling of Resting and Moving Active Droplets
• Tractionless Self-Propulsion of Active Drops
• How many ways a cell can move: the modes of self-propulsion of an active drop
• Symmetry-breaking, motion and bistability of active drops through polarization-surface coupling