论文标题
$ \ mathbf {q} $ - 具有单轴约束的张量模型
The $\mathbf{Q}$-tensor Model with Uniaxial Constraint
论文作者
论文摘要
本章介绍了列液晶(LCS)及其数值模拟的建模。我们从LCS的基本物理学概述开始,并讨论其许多应用中的一些应用。接下来,我们深入研究获得宏观顺序参数所需的建模参数,该参数可用于制定连续模型。然后,我们调查了不同的连续描述,即Oseen-Frank,Ericksen和Landau-Degennes($ \ Mathbf {q} $ - 张量)模型,这些模型实际上是对LC材料进行建模,例如各向异性弹性材料。特别是,我们回顾了三种不同的连续模型的基础数学理论,并突出了使用这些模型的不同权衡。 接下来,我们通过对各种方法的调查来考虑这些模型的数值模拟,重点是Ericksen模型。然后,我们展示如何将来自Ericksen模型的技术与Landau-Degennes模型结合使用,以产生$ \ MathBf {Q} $ - 张量模型,该模型可以完全强制执行单坐骨性,这与对许多Nematic LC系统建模很重要。接下来是使用$γ$ -Convergence的工具来证明我们的离散方法合理的深入数值分析。我们还显示了几个数值实验和与标准Landau-Degennes模型的比较。
This chapter is about the modeling of nematic liquid crystals (LCs) and their numerical simulation. We begin with an overview of the basic physics of LCs and discuss some of their many applications. Next, we delve into the modeling arguments needed to obtain macroscopic order parameters which can be used to formulate a continuum model. We then survey different continuum descriptions, namely the Oseen-Frank, Ericksen, and Landau-deGennes ($\mathbf{Q}$-tensor) models, which essentially model the LC material like an anisotropic elastic material. In particular, we review the mathematical theory underlying the three different continuum models and highlight the different trade-offs of using these models. Next, we consider the numerical simulation of these models with a survey of various methods, with a focus on the Ericksen model. We then show how techniques from the Ericksen model can be combined with the Landau-deGennes model to yield a $\mathbf{Q}$-tensor model that exactly enforces uniaxiality, which is relevant for modeling many nematic LC systems. This is followed by an in-depth numerical analysis, using tools from $Γ$-convergence, to justify our discrete method. We also show several numerical experiments and comparisons with the standard Landau-deGennes model.