Flow of supercooled liquids under dipolar force field

Kento Maeda; Atsushi Ikeda

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arXiv · 2409.16725

Flow of supercooled liquids under dipolar force field

Kento Maeda·Atsushi Ikeda

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Abstract

The viscosity of supercooled liquids notably increases with decreasing temperature, leading to solidification through a glass transition. This process is accompanied by dynamic heterogeneity, characterized by persistent dynamic spatial correlations. This study investigates how dynamic heterogeneity influences the applicability of the Navier-Stokes equations to the flow of supercooled liquids. Utilizing molecular dynamics simulations, we subjected a two-dimensional supercooled liquid to a localized dipolar force field and compared the resulting steady velocity field with the prediction from the Navier-Stokes equations. Our approach captures a significant breakdown of the Navier-Stokes equations in real space; specifically, supercooled liquids flow more rapidly near the external force than the prediction from the Navier-Stokes equations. Furthermore, this deviation is enhanced by the supercooling and is accompanied by the growth of dynamic heterogeneity.

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Kento Maeda, Atsushi Ikeda. 2024-09-25. Flow of supercooled liquids under dipolar force field. https://arxiv.org/abs/2409.16725

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