Nonlinear mechanics of phase-change-induced accretion

TL;DR

This paper develops a continuum theory for solidification considering finite-strain thermoelasticity, addressing the gap of decoupled thermal and elastic analyses and exploring elastic effects during phase change.

Contribution

It introduces a coupled thermoelastic model for solidification as an accretion process with a moving boundary, solved numerically for spherical inward solidification.

Findings

Elastic deformations influence solidification dynamics.

Numerical results differ from rigid boundary assumptions.

Parametric studies reveal the role of elasticity in phase change.

Abstract

In this paper, we formulate a continuum theory of solidification within the context of finite-strain coupled thermoelasticity. We aim to fill a gap in the existing literature, as the existing studies on solidification typically decouple the thermal problem (the classical Stefan's problem) from the elasticity problem, and often limit themselves to linear elasticity with small strains. Treating solidification as an accretion problem, with the growth velocity correlated with the jump in the heat flux across the boundary, it presents an initial boundary-value problem (IBVP) over a domain whose boundary location is a priori unknown. This IBVP is solved numerically for the specific example of radially inward solidification in a spherical container. Several parametric studies are conducted to compare the numerical results with the rigid cases in the literature and gain insights into the role of elastic deformations in solidification.