论文标题
Cahn-Hilliard模型,与粘弹性结合具有较大变形
A Cahn-Hilliard model coupled to viscoelasticity with large deformations
论文作者
论文摘要
我们提出了一种新的相位场模型,该模型与粘弹性具有较大的变形,该变形是从具有弹性特性和液相的相的相位界面混合模型获得的。该模型是在Eulerian配置中配制的,它是通过施加混合组件的质量平衡以及来自虚拟力原理的广义形式的动量平衡来得出的。后者考虑了与混合物组成部分之间的微观相互作用相关的微效率和显微压力系统的存在,并考虑到这些相之间的摩擦,以及与其粘弹性行为相关的宏观体系和宏观肌肉的系统。该系统的自由能密度作为CAHN-HILLIARD项和弹性多凸项的总和,在弹性贡献中具有相位场变量与弹性变形梯度之间的耦合。在等热情况下,符合第二种热力学定律的机械版本的一般本质假设。我们研究了通用模型的简化和正则化版本的弱解决方案的全球存在,该模型考虑了新霍克类型的不可压缩的弹性自由能,其弹性系数取决于相位场的变量。正则化适当设计以处理弹性能密度中相位场变量与弹性变形梯度之间的耦合。分析在两个和三个空间维度上进行。
We propose a new class of phase field models coupled to viscoelasticity with large deformations, obtained from a diffuse interface mixture model composed by a phase with elastic properties and a liquid phase. The model is formulated in the Eulerian configuration and it is derived by imposing the mass balance for the mixture components and the momentum balance that comes from a generalized form of the principle of virtual powers. The latter considers the presence of a system of microforces and microstresses associated to the microscopic interactions between the mixture's constituents together with a system of macroforces and macrostresses associated to their viscoelastic behavior, taking into account also the friction between the phases. The free energy density of the system is given as the sum of a Cahn-Hilliard term and an elastic polyconvex term, with a coupling between the phase field variable and the elastic deformation gradient in the elastic contribution. General constitutive assumptions complying with a mechanical version of the second law of thermodynamics in isothermal situations are taken. We study the global existence of a weak solution for a simplified and regularized version of the general model, which considers an incompressible elastic free energy of Neo-Hookean type with elastic coefficients depending on the phase field variable. The regularization is properly designed to deal with the coupling between the phase field variable and the elastic deformation gradient in the elastic energy density. The analysis is made both in two and three space dimensions.