Hydrodynamics of self-propelled hard rods

Aparna Baskaran; M. Cristina Marchetti

doi:10.1103/physreve.77.011920

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arXiv · 0708.2401

Hydrodynamics of self-propelled hard rods

Aparna Baskaran·M. Cristina Marchetti

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Abstract

Motivated by recent simulations and by experiments on aggregation of gliding bacteria, we study a model of the collective dynamics of self-propelled hard rods on a substrate in two dimensions. The rods have finite size, interact via excluded volume and their dynamics is overdamped by the interaction with the substrate. Starting from a microscopic model with non-thermal noise sources, a continuum description of the system is derived. The hydrodynamic equations are then used to characterize the possible steady states of the systems and their stability as a function of the particles packing fraction and the speed of self propulsion.

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Aparna Baskaran, M. Cristina Marchetti. 2007-08-17. Hydrodynamics of self-propelled hard rods. https://doi.org/10.1103/physreve.77.011920

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