Run-and-tumble particles with hydrodynamics: sedimentation, trapping and upstream swimming

R. W. Nash; R. Adhikari; J. Tailleur; M. E. Cates

doi:10.1103/physrevlett.104.258101

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arXiv · 1003.1996

Run-and-tumble particles with hydrodynamics: sedimentation, trapping and upstream swimming

R. W. Nash·R. Adhikari·J. Tailleur·M. E. Cates

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Abstract

We simulate by lattice Boltzmann the nonequilibrium steady states of run-and-tumble particles (inspired by a minimal model of bacteria), interacting by far-field hydrodynamics, subject to confinement. Under gravity, hydrodynamic interactions barely perturb the steady state found without them, but for particles in a harmonic trap such a state is quite changed if the run length is larger than the confinement length: a self-assembled pump is formed. Particles likewise confined in a narrow channel show a generic upstream flux in Poiseuille flow: chiral swimming is not required.

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R. W. Nash, R. Adhikari, J. Tailleur, M. E. Cates. 2010-06-30. Run-and-tumble particles with hydrodynamics: sedimentation, trapping and upstream swimming. https://doi.org/10.1103/physrevlett.104.258101

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