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arXiv · 2503.19985

Scaling laws for passive polymer dynamics in active turbulence

Zahra K. Valei·Tyler N. Shendruk
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Abstract

Biological systems commonly combine intrinsically out-of-equilibrium active components with passive polymeric inclusions to produce unique material properties. To explore these composite systems, idealized models - such as polymers in active fluids - are essential to develop a predictive theoretical framework. We simulate a single, freely jointed passive chain in two-dimensional active turbulence. Active flows advect the polymer, producing a substantially enhanced diffusivity. Our results reveal that the dimensionless diffusivity obeys scaling laws governed by the P\'eclet, Weissenberg, and Ericksen numbers, which paves the way for designing active/polymeric hybrid materials with predictable properties that differ significantly from those of nondeformable inclusions.

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Zahra K. Valei, Tyler N. Shendruk. 2025-03-25. Scaling laws for passive polymer dynamics in active turbulence. https://arxiv.org/abs/2503.19985

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