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arXiv · 2006.08895

Reciprocal microswimmers in a viscoelastic fluid

Kento Yasuda·Mizuki Kuroda·Shigeyuki Komura
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Abstract

We suggest several reciprocal swimming mechanisms that lead to a locomotion only in viscoelastic fluids. The first situation is to have a difference between the two amplitudes of the oscillatory arm motion for a three-sphere microswimmer. The second situation is when one of the frequencies of the arm motion is twice as large as the other one for a three-sphere microswimmer. The third situation is when the sphere sizes are different for a two-sphere microswimmer. In all these three cases, the average velocity is proportional to the imaginary part of the complex shear viscosity of a surrounding viscoelastic medium. It is essential for a micromachine to break its structural symmetry in order to swim in a viscoelastic fluid by performing reciprocal body motions.

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Kento Yasuda, Mizuki Kuroda, Shigeyuki Komura. 2020-06-16. Reciprocal microswimmers in a viscoelastic fluid. https://doi.org/10.1063/5.0018540

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