English

Phase separation in the advective Cahn-Hilliard equation

Analysis of PDEs 2022-07-20 v2 Chaotic Dynamics Fluid Dynamics

Abstract

The Cahn--Hilliard equation is a classic model of phase separation in binary mixtures that exhibits spontaneous coarsening of the phases. We study the Cahn--Hilliard equation with an imposed advection term in order to model the stirring and eventual mixing of the phases. The main result is that if the imposed advection is sufficiently mixing then no phase separation occurs, and the solution instead converges exponentially to a homogeneous mixed state. The mixing effectiveness of the imposed drift is quantified in terms of the dissipation time of the associated advection-hyperdiffusion equation, and we produce examples of velocity fields with a small dissipation time. We also study the relationship between this quantity and the dissipation time of the standard advection-diffusion equation.

Keywords

Cite

@article{arxiv.1912.12714,
  title  = {Phase separation in the advective Cahn-Hilliard equation},
  author = {Yu Feng and Yuanyuan Feng and Gautam Iyer and Jean-Luc Thiffeault},
  journal= {arXiv preprint arXiv:1912.12714},
  year   = {2022}
}

Comments

21 pages, 8 figures. v2: changes following referee reports

R2 v1 2026-06-23T12:58:32.202Z