On the cross-streamline lift of microswimmers in viscoelastic flows


The current work studies the dynamics of a microswimmer in the pressure-driven flow of a weakly viscoelastic fluid. Employing the second-order fluid model, we show that the self-propelling swimmer experiences a viscoelastic swimming lift in addition to the well-known passive lift that arises from its resistance to shear flow. Using the reciprocal theorem, we evaluate analytical expressions for the swimming lift experienced by neutral and pusher/puller-type swimmers and show that they depend on the hydrodynamic signature associated with the swimming mechanism. We find that, in comparison to passive particles, the focusing of} neutral swimmers towards the centerline can be significantly accelerated, while for force-dipole swimmers no net modification in cross-streamline migration occurs.

Supplementary files

Article information

Article type
15 Sep 2021
24 Nov 2021
First published
24 Nov 2021
This article is Open Access
Creative Commons BY license

Soft Matter, 2021, Accepted Manuscript

On the cross-streamline lift of microswimmers in viscoelastic flows

A. Choudhary and H. Stark, Soft Matter, 2021, Accepted Manuscript , DOI: 10.1039/D1SM01339D

This article is licensed under a Creative Commons Attribution 3.0 Unported Licence. You can use material from this article in other publications without requesting further permissions from the RSC, provided that the correct acknowledgement is given.

Read more about how to correctly acknowledge RSC content.

Social activity