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arXiv · 2307.01298

Extremely Persistent Dense Active Fluids

Grzegorz Szamel·Elijah Flenner
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Abstract

We examine the dependence of the dynamics of three-dimensional active fluids on persistence time $\tau_p$ and average self-propulsion force $f$. In the large persistence time limit many properties of these fluids become $\tau_p$-independent. These properties include the mean squared velocity, the self-intermediate scattering function, the shear-stress correlation function and the low-shear-rate viscosity. We find that for a given $f$ in the large $\tau_p$ limit the mean squared displacement is independent of the persistence time for times shorter than $\tau_p$ and the long-time self-diffusion coefficient is proportional to the persistence time. For a large range of self-propulsion forces the large persistence time limits of many properties depend on $f$ as power laws.

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Grzegorz Szamel, Elijah Flenner. 2023-07-03. Extremely Persistent Dense Active Fluids. https://arxiv.org/abs/2307.01298

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