Active particles in linear viscoelastic fluids and the scallop theorem

Gwynn J. Elfring; Eric Lauga

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arXiv · 2009.08514

Active particles in linear viscoelastic fluids and the scallop theorem

Gwynn J. Elfring·Eric Lauga

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Abstract

We derive a general formula for the inertialess dynamics of active particles in linear viscoelastic fluids by means of a modified reciprocal theorem. We then demonstrate that force-free active particles in Maxwell-like linear viscoelastic fluids with no retardation have exactly the same dynamics as in Newtonian fluids. In contrast, active particles in Jeffreys-like fluids with retardation can display markedly different dynamics, including net motion under reciprocal actuation thereby breaking the scallop theorem.

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Gwynn J. Elfring, Eric Lauga. 2020-09-17. Active particles in linear viscoelastic fluids and the scallop theorem. https://arxiv.org/abs/2009.08514

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