Transcritical transition of the fluid around the interface

TL;DR

This paper uses molecular dynamics simulations to explore the transcritical transition of fluids, revealing a new transcritical region with unique properties that replaces the traditional interface.

Contribution

It introduces the concept of a transcritical region as a substitute for the traditional interface and characterizes its physical properties and surface tension behavior.

Findings

Discovered a transcritical region covering three fluid states.

Observed highly non-linear temperature and density distributions.

Found surface tension exists throughout the transcritical region, proportional to -ρ∇²ρ.

Abstract

In this letter, we provide fundamental insights into the dynamic transcritical transition process using molecular dynamics simulations. A transcritical region, which covers three different fluid states, was discovered as a substitute for the traditional interface. The physical properties, such as temperature and density, exhibited a highly non-linear distribution in the transcritical region. Meanwhile, the surface tension was found to exist throughout the transcritical region, and the magnitude was directly proportional to $ - \rho \cdot {\nabla ^2}\rho $