Flow of supercooled liquids under dipolar force field

TL;DR

This paper explores how dynamic heterogeneity in supercooled liquids causes deviations from classical Navier-Stokes predictions, especially under dipolar force fields, revealing a breakdown of traditional flow models.

Contribution

It demonstrates through simulations that supercooled liquids exhibit significant flow deviations from Navier-Stokes equations due to dynamic heterogeneity and supercooling effects.

Findings

Supercooled liquids flow faster near external forces than Navier-Stokes predicts.

Deviations from Navier-Stokes increase with supercooling.

Dynamic heterogeneity correlates with flow deviations.

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.