Mathematical Models for Solid-Solid Phase Transitions Driven by Configurational Forces

2013 ◽  
Vol 774-776 ◽  
pp. 488-492
Author(s):  
Pei Cheng Zhu
Keyword(s):  
Phase Transitions ◽  
Mathematical Models ◽  
Shape Memory ◽  
Phase Field ◽  
Mean Curvature ◽  
Solid Phase ◽  
Configurational Forces ◽  
Two Phase ◽  
Phase Field Models ◽  
Martensitic Phase Transformations

Two phase-field models for solid-solid phase transitions driven by configurational forces are reviewed, and the formulation of the models is briefly presented for the non-conserved case, as an example. Applications include martensitic phase transformations in, e.g., shape memory alloys and sintering in ceramic producing. They are compared with two other famous models for phase transitions that are driven by mean curvature.

scholarly journals A ternary Cahn–Hilliard–Navier–Stokes model for two-phase flow with precipitation and dissolution

2020 ◽  
pp. 1-35
Author(s):  
Christian Rohde ◽  
Lars von Wolff
Keyword(s):  
Phase Field ◽  
Stokes Equations ◽  
Solid Phase ◽  
Immiscible Fluids ◽  
Sharp Interface ◽  
Ion Concentration ◽  
Navier Stokes ◽  
Interface Model ◽  
Sharp Interface Model ◽  
Two Phase

We consider the incompressible flow of two immiscible fluids in the presence of a solid phase that undergoes changes in time due to precipitation and dissolution effects. Based on a seminal sharp interface model a phase-field approach is suggested that couples the Navier–Stokes equations and the solid’s ion concentration transport equation with the Cahn–Hilliard evolution for the phase fields. The model is shown to preserve the fundamental conservation constraints and to obey the second law of thermodynamics for a novel free energy formulation. An extended analysis for vanishing interfacial width reveals that in this limit the sharp interface model is recovered, including all relevant transmission conditions. Notably, the new phase-field model is able to realize Navier-slip conditions for solid–fluid interfaces in the limit.

scholarly journals Фазовые превращения в однокомпонентных многофазных системах: фазово-полевой подход

2022 ◽  
Vol 92 (2) ◽  
pp. 187
Author(s):  
В.Г. Лебедев
Keyword(s):  
Phase Transitions ◽  
Gibbs Energy ◽  
Phase Field ◽  
Complete System ◽  
Nonequilibrium System ◽  
Phase Model ◽  
Multiphase Model ◽  
Two Phase ◽  
Dissipative Dynamics ◽  
Phase Fields

The problems of constructing a multiphase model of the phase field for the processes of phase transitions of the first kind are considered. Based on the Gibbs energy of the complete system expressed in terms of antisymmetrized combinations of phase fields, it is shown that the equations of dissipative dynamics of a locally nonequilibrium system follow from the condition of its monotonic decrease, preserving the normalization of the sum of variables by one and the following properties of the previously known two-phase model.

Isogeometric Analysis of 3D Dynamic Thermo-Mechanical Phase-Field Model for Cubic-to-Tetragonal Phase Transformations in Shape Memory Alloys

2015 ◽  
Author(s):  
Rakesh Dhote ◽  
Kamran Behdinan
Keyword(s):  
Shape Memory ◽  
Phase Transformations ◽  
Phase Field ◽  
Isogeometric Analysis ◽  
Domain Walls ◽  
Landau Theory ◽  
Phase Field Model ◽  
Diffuse Interface ◽  
Free Energy Function ◽  
Martensitic Phase Transformations

In this paper, we study the dynamic thermo-mechanical behaviors of 3D shape memory alloy (SMA) nanostructures using the phase-field (PF) model. The PF model is based on the Ginzburg-Landau theory and requires a non-convex free energy function for an adequate description of the cubic-to-tetragonal martensitic phase transformations. We have developed a model that includes domain walls, treated as a diffuse interface, which leads to a fourth-order differential equation in a strain-based order parameter PF model. Arising numerical challenges have been overcome based on an isogeometric analysis (IGA) framework. Microstructure morphology evolution and consequent thermo-mechanical properties have been studied on SMA nanostructures of different geometries. The numerical results are in agreement with experimental observations. The developed coupled dynamic model has provided a better understanding of underlying microstructures and behaviors, which can be used for development of better SMA-based devices.

Phase-Field Numerical Simulation of Pure Free Dendritic Growth Using Wheeler and Karma Model

2011 ◽  
Vol 421 ◽  
pp. 90-97 ◽  
Author(s):  
Yun Chen ◽  
Na Min Xiao ◽  
Xiu Hong Kang ◽  
Dian Zhong Li
Keyword(s):  
Phase Field ◽  
Field Model ◽  
Phase Field Model ◽  
Dendrite Growth ◽  
Adaptive Finite Element Method ◽  
Adaptive Finite Element ◽  
Two Phase ◽  
Phase Field Models ◽  
Careful Comparison ◽  
Undercooled Melts

To understand the dendrite formation during solidification phase-field model has become a powerful numerical method of simulating crystal growth in recent years. Two phase-field models due to Wheeler et al. and Karma et al., respectively, have been employed for modeling the dendrite growth worldwidely. The comparison of the two models was performed. Then using the adaptive finite element method, both models were solved to simulate a free dendrite growing from highly undercooled melts of nickel at various undercoolings. The simulated results showed that the discrepancy between the two phase-field models is negligible. Careful comparison of the phase-filed simulations with LKT(BCT) theory and experimental data were carried out, which demonstrated that the phase-field models are able to quantitatively simulate the dendrite growth of nickel at low undercoolings, however, at undercoolings above ten percent of the melting point (around 180K), the simulated velocities by Wheeler and Karma model as well as the analytical predictions overestimated the reported experiment results.

A regularized isothermal phase-field model of two-phase solid–fluid mixture and its spatial dissipative discretization equations

2021 ◽  
Vol 36 (4) ◽  
pp. 197-217
Author(s):  
Vladislav Balashov
Keyword(s):  
Phase Field ◽  
Solid Phase ◽  
Numerical Study ◽  
Strain Tensor ◽  
Phase Field Model ◽  
Evolutionary Equation ◽  
Two Phase ◽  
Fluid Mixture ◽  
Component Mixture ◽  
Eulerian Description

Abstract The present paper is devoted to a model describing a two-phase isothermal mixture, in which one of the phases obeys solid-like (namely, elastic) rheology. A fully Eulerian description is considered. To describe the stress–strain behaviour of the solid phase the elastic energy term is added to the Helmholtz free energy. The term depends on Almansi strain tensor. In its turn, the strain tensor is defined as the solution of the corresponding evolutionary equation. Considered model belongs to the phase field family. Formally it describes two-component mixture and uses mass densities of the components as order parameters. A distinctive feature of the considered model is its preliminary regularization according to the quasi-hydrodynamic framework. The dissipativity in total energy is proved when periodic boundary conditions are imposed. A spatial dissipative semi-discrete (continuous in time and discrete in space) scheme based on staggered grids is suggested. The theoretical results remain valid in the absence of the regularization. The results of a numerical study in a 2D setting are presented.

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