A phase field model of Cahn-Hilliard type for tumour growth with mechanical effects and damage
Giulia Cavalleri
TL;DR
The paper develops a diffuse-interface phase-field model for tumor growth that couples a Cahn–Hilliard equation for tissue phase with nutrient diffusion, a hyperbolic balance for mechanics, and a novel damage variable governed by a parabolic differential inclusion. The main contribution is a rigorous global-in-time existence proof for weak solutions, achieved by a time-discretised, regularised scheme that employs a convex–concave energy split and Moreau–Yosida regularisation, accompanied by discrete energy estimates and compactness arguments to pass to the limit. The analysis handles strong nonlinearity and coupling, including a $p$-Laplacian damage term and a nonconvex elastic energy, while ensuring nutrient bounds and adherence to a comprehensive weak formulation. This work provides a mathematically rigorous foundation for biologically relevant CH-type models with mechanical effects and reversible tissue damage, enabling reliable simulations of tumor evolution under nutrition and mechanical loading.
Abstract
We introduce a new diffuse interface model for tumour growth in the presence of a nutrient, in which we take into account mechanical effects and reversible tissue damage. The highly nonlinear PDEs system mainly consists of a Cahn-Hilliard type equation that describes the phase separation process between healthy and tumour tissue coupled to a parabolic reaction-diffusion equation for the nutrient and a hyperbolic equation for the balance of forces, including inertial and viscous effects. The main novelty of this work is the introduction of cellular damage, whose evolution is ruled by a parabolic differential inclusion. In this paper, we prove a global-in-time existence result for weak solutions by passing to the limit in a time-discretised and regularised version of the system.
