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Non-equilibrium clustering of self-propelled rods

F. Peruani·A. Deutsch·M. Baer
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Abstract

Motivated by aggregation phenomena in gliding bacteria, we study collective motion in a twodimensional model of active, self-propelled rods interacting through volume exclusion. In simulations with individual particles, we find that particle clustering is facilitated by a sufficiently large packing fraction (eta) or length-to-width ratio (kappa). The transition to clustering in simulations is well captured by a mean-field model for the cluster size distribution, which predicts that the transition values kappa_c of the aspect ratio for a fixed packing fraction is given by kappa_c = C/eta - 1 where C is a constant.

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F. Peruani, A. Deutsch, M. Baer. 2006-04-20. Non-equilibrium clustering of self-propelled rods. https://doi.org/10.1103/physreve.74.030904

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