Simple model squirmers with tunable velocity

TL;DR

This paper introduces a simple model of self-propelling liquid droplets, called squirmers, which mimic protozoal locomotion and allow control over velocity and flow mode through parameter variation.

Contribution

It presents a novel, tunable squirmer model with weak medium interaction, enabling control over propulsion velocity and flow patterns.

Findings

Velocity and flow mode can be independently controlled.

Locomotion paths are not self-avoiding due to weak medium interaction.

Model closely mimics protozoal movement.

Abstract

We present a scheme of self-propelling liquid droplets which closely mimics the locomotion of some protozoal organisms, so-called squirmers. In contrast to other schemes proposed earlier, locomotion paths are not self-avoiding, since the effect of the squirmer on the surrounding medium is weak. Our results suggest that not only the velocity, but also the mode of operation (i.e., the spherical harmonics of the flow field) can be controlled by appropriate variation of parameters.