Homogeneous Nucleation of Sheared Liquids: Advances and Insights from Simulations and Theory

TL;DR

This paper reviews recent computational and theoretical advances in understanding how shear influences homogeneous nucleation in simple liquids, highlighting the effects on nucleation energy and kinetics, and discussing experimental and complex system insights.

Contribution

It unifies recent simulation and theory techniques to elucidate shear effects on nucleation, including influences of temperature and supersaturation, and extends discussion to complex systems.

Findings

Shear increases the energetic barrier to nucleation.

Shear enhances nucleation kinetics.

Simulations and theory agree on shear's dual role.

Abstract

One of the most ubiquitous and technologically important phenomena in nature is the nucleation of homogeneous flowing systems. The microscopic effects of shear on a nucleating system are still imperfectly understood, although in recent years a consistent picture has emerged. The opposing effects of shear can be split into two major contributions for simple liquids: increase of the energetic cost of nucleation, and enhancement of the kinetics. In this perspective, we describe the latest computational and theoretical techniques which have been developed over the past two decades. We collate and unify the overarching influences of shear, temperature, and supersaturation on the process of homogeneous nucleation. Experimental techniques and capabilities are discussed, against the backdrop of results from simulations and theory. Although we primarily focus on simple liquids, we also touch upon the sheared nucleation of more complex systems, including glasses and polymer melts. We speculate on the promising directions and possible advances that could come to fruition in the future.