Hydrodynamics of chiral liquids and suspensions

TL;DR

This paper develops hydrodynamic equations for chiral liquids and suspensions, revealing unique flow-induced forces and particle separation effects due to chirality, which are absent in non-chiral Newtonian fluids.

Contribution

It introduces a theoretical framework for describing the hydrodynamics of chiral fluids and suspensions, highlighting symmetry-breaking effects and flow-induced particle separation.

Findings

Chiral liquids exert perpendicular forces on boundaries in flow.

Flow causes spatial separation of particles based on chirality.

Chiral suspensions exhibit properties similar to racemic mixtures in flow.

Abstract

We obtain hydrodynamic equations describing a fluid consisting of chiral molecules or a suspension of chiral particles in a Newtonian fluid. The stresses arising in a flowing chiral liquid have a component forbidden by symmetry in a Newtonian liquid. For example, a chiral liquid in a Poiseuille flow between parallel plates exerts forces on the plates, which are perpendicular to the flow. A generic flow results in spatial separation of particles of different chirality. Thus even a racemic suspension will exhibit chiral properties in a generic flow. A suspension of particles of random shape in a Newtonian liquid is described by equations which are similar to those describing a racemic mixture of chiral particles in a liquid.