Well-posedness and relaxation in a simplified model for viscoelastic phase separation via Hilbertian gradient flows

Fuente: arXiv
Saved in:
Bibliographic Details
Main Authors: Gau, Moritz Immanuel, Hopf, Katharina
Format: Preprint
Published: 2025
Subjects:
Online Access:
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1866918128493002752
author Gau, Moritz Immanuel
Hopf, Katharina
author_facet Gau, Moritz Immanuel
Hopf, Katharina
contents This article is concerned with a gradient-flow approach to a Cahn-Hilliard model for viscoelastic phase separation introduced by Zhou et al. (Phys. Rev. E, 2006) in its variant with constant mobility. By means of time-incremental minimisation and generalised contractivity estimates, we establish the global well-posedness of the Cauchy problem for moderately regular initial data. For general finite-energy data we obtain the existence of gradient-flow solutions and a stability estimate of weak-strong type. We further study the asymptotic behaviour for relaxation time and bulk modulus depending on a small parameter. Depending on the scaling, we recover the Cahn-Hilliard, the mass-conserving Allen-Cahn or the viscous Cahn-Hilliard equation. A challenge in the well-posedness analysis is the failure of semiconvexity of the appropriate driving functional, which is caused by a phase-dependence of the bulk modulus.
format Preprint
id arxiv_https___arxiv_org_abs_2508_10722
institution arXiv
publishDate 2025
record_format arxiv
spellingShingle Well-posedness and relaxation in a simplified model for viscoelastic phase separation via Hilbertian gradient flows
Gau, Moritz Immanuel
Hopf, Katharina
Analysis of PDEs
This article is concerned with a gradient-flow approach to a Cahn-Hilliard model for viscoelastic phase separation introduced by Zhou et al. (Phys. Rev. E, 2006) in its variant with constant mobility. By means of time-incremental minimisation and generalised contractivity estimates, we establish the global well-posedness of the Cauchy problem for moderately regular initial data. For general finite-energy data we obtain the existence of gradient-flow solutions and a stability estimate of weak-strong type. We further study the asymptotic behaviour for relaxation time and bulk modulus depending on a small parameter. Depending on the scaling, we recover the Cahn-Hilliard, the mass-conserving Allen-Cahn or the viscous Cahn-Hilliard equation. A challenge in the well-posedness analysis is the failure of semiconvexity of the appropriate driving functional, which is caused by a phase-dependence of the bulk modulus.
title Well-posedness and relaxation in a simplified model for viscoelastic phase separation via Hilbertian gradient flows
topic Analysis of PDEs
url https://arxiv.org/abs/2508.10722