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arXiv · 2602.16408

Three dimensional contractile droplet under confinement

Adriano Tiribocchi·Marco Lauricella·Andrea Montessori·Sauro Succi
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Abstract

We numerically study the dynamics of a three-dimensional contractile fluid droplet in the bulk and under confinement. We show that varying activity leads to a variety of shapes and motile regimes whose motion is driven by an interplay between spontaneous flows and elasticity. In the bulk the droplet self-propels unidirectionally, acquiring either an almost spherical shape at intermediate activity or a peanut-like geometry for larger values. Under confinement, the droplet exhibits a previously unreported oscillating dynamics characterized by periodic hits against opposite walls of a microchannel while moving forward. These results could be of interest for the study of artificial microswimmers and their biological analogs, such as living cells.

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Adriano Tiribocchi, Marco Lauricella, Andrea Montessori, Sauro Succi. 2026-02-18. Three dimensional contractile droplet under confinement. https://arxiv.org/abs/2602.16408

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