Modeling a spheroidal microswimmer and cooperative swimming in thin films

TL;DR

This paper introduces an analytically solvable hydrodynamic model for spheroidal microswimmers with surface velocity modes, and explores their cooperative behavior through simulations, revealing stable wedge-like formations.

Contribution

It develops a new spheroidal squirmer model that generalizes spherical models and demonstrates cooperative swimming behavior through multiparticle collision dynamics simulations.

Findings

The model reduces to classical spherical squirmer models in specific limits.

Simulations show stable cooperative wedge formations among pullers.

The model provides insights into microswimmer interactions in confined geometries.

Abstract

We propose a hydrodynamic model for a spheroidal microswimmer with two tangential surface velocity modes. This model is analytically solvable and reduces to Lighthill's and Blake's spherical squirmer model in the limit of equal major and minor semi-axes. Furthermore, we present an implementation of such a spheroidal squirmer by means of multiparticle collision dynamics simulations. We investigate its properties as well as the scattering of two spheroidal squirmers in a slit geometry. Thereby we find a stable fixed point, where two pullers swim cooperatively forming a wedge-like conformation with a small constant angle.