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arXiv · 1102.3894

Undulatory swimming in viscoelastic fluids

Xiaoning Shen·P. E. Arratia
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Abstract

The effects of fluid elasticity on the swimming behavior of the nematode \emph{Caenorhabditis elegans} are experimentally investigated by tracking the nematode's motion and measuring the corresponding velocity fields. We find that fluid elasticity hinders self-propulsion. Compared to Newtonian solutions, fluid elasticity leads to 35% slower propulsion speed. Furthermore, self-propulsion decreases as elastic stresses grow in magnitude in the fluid. This decrease in self-propulsion in viscoelastic fluids is related to the stretching of flexible molecules near hyperbolic points in the flow.

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Xiaoning Shen, P. E. Arratia. 2011-05-13. Undulatory swimming in viscoelastic fluids. https://doi.org/10.1103/physrevlett.106.208101

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