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arXiv · 2611.08205

Hydrodynamic interaction in Lattice Fokker Planck for dilute polymer dynamics

Shiwani Singh·Santosh Ansumali
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Abstract

We extend the BGK-type kinetic model for polymer dumbbells and its lattice Boltzmann implementation by incorporating hydrodynamic interaction (HI) effects to accurately recover the slow-variable dynamics governed by the Smoluchowski equation. Unlike Brownian dynamics approaches, which demand the computationally expensive evaluation of the square root of the configuration-dependent diffusion tensor at every time step, this kinetic method is straightforward to implement and avoids such overhead entirely. Consequently, it achieves a significant reduction in computational cost. We validate the model in steady and transient shear flows, demonstrating its ability to capture the distinct signatures of hydrodynamic interactions on bulk rheological properties.

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Shiwani Singh, Santosh Ansumali. 2026-11-05. Hydrodynamic interaction in Lattice Fokker Planck for dilute polymer dynamics. https://arxiv.org/abs/2611.08205

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