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arXiv · 2008.03389

Transport barriers to self-propelled particles in fluid flows

Simon A. Berman·John Buggeln·David A. Brantley·Kevin Mitchell·Thomas H. Solomon
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Abstract

We present theory and experiments demonstrating the existence of invariant manifolds that impede the motion of microswimmers in two-dimensional fluid flows. One-way barriers are apparent in a hyperbolic fluid flow that block the swimming of both smooth-swimming and run-and-tumble \emph{Bacillus subtilis} bacteria. We identify key phase-space structures, called swimming invariant manifolds (SwIMs), that serve as separatrices between different regions of long-time swimmer behavior. When projected into $xy$-space, the edges of the SwIMs act as one-way barriers, consistent with the experiments.

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Simon A. Berman, John Buggeln, David A. Brantley, Kevin Mitchell, Thomas H. Solomon. 2020-08-07. Transport barriers to self-propelled particles in fluid flows. https://doi.org/10.1103/physrevfluids.6.l012501

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