Self-organisation of spermatozoa in bulk suspensions via unsteady elastohydrodynamic interactions

Nanami Taketoshi; Toshihiro Omori; Takuji Ishikawa

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arXiv · 2302.10572

Self-organisation of spermatozoa in bulk suspensions via unsteady elastohydrodynamic interactions

Nanami Taketoshi·Toshihiro Omori·Takuji Ishikawa

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Abstract

We developed a mechanical model of spermatozoal swimming in bulk suspensions. We traced the spatiotemporal elastohydrodynamic interactions and found that spermatozoa engaged in self-organisation: flagellar undulatory motion generated a stable polar order. Conventional microswimmer theories use time-averaged stress fields to predict that the cellular structure is unstable. However, our present results reveal a novel self-organisation mechanism attributable to unsteady hydrodynamic interactions. We thus contribute to the theory of active soft matter dynamics.

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Nanami Taketoshi, Toshihiro Omori, Takuji Ishikawa. 2023-02-21. Self-organisation of spermatozoa in bulk suspensions via unsteady elastohydrodynamic interactions. https://arxiv.org/abs/2302.10572

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