Mechanical model of lung parenchyma as a two-phase porous medium
Mechanical model of lung parenchyma as a two-phase porous medium
复制标题
肺实质作为两相多孔介质的力学模型
DOI：
10.1007/bf00614816
复制
发表时间：
1993
影响因子：
2.7
通讯作者：
P. Kowalczyk
中科院分区：
文献类型：
--
作者：
P. Kowalczyk
在微观和宏观水平上简要描述了肺的解剖结构和几何形状。肺实质的概念-一个宏观连续的介质，其机械性能的结果，从那些微观结构成分-已适应。讨论了本构模型中提出的简化假设。在介质中可以区分出两种相：固体相-在微观尺度上以薄壁组织结构形式出现的高度可变形的非线性弹性骨架-以及流体相-通过结构过滤的完美气体（空气）。推导了两相的一般本构关系及其力学相互作用。进一步，建立了准静态耦合问题的基本微分方程组。包括大变形、材料非线性和渗透率对骨架变形的依赖。从有限元的角度出发，给出了该问题的矩阵表达式。提出了一种隐式迭代时间积分方案。用简单的数值试验结果说明了该算法。
The anatomy and geometry of the lung at the micro- and macroscopic level have been described briefly. A notion of lung parenchyma — a macroscopically continuous medium whose mechanical properties result from those of microstructural components — has been adapted. Simplifying assumptions propounded in the constitutive model have been discussed. Two phases have been distinguished in the medium: the solid phase — a highly deformable, nonlinearly elastic skeleton in the form of a thin-walled tissue structure on the micro-scale — and the fluid phase — perfect gas (air) filterating through the structure. General constitutive relations for both phases and their mechanical interactions have ben formulated. Further, the fundamental set of differential equations of the quasi-static coupled problem has been developed. Large deformations, material nonlinearities, and dependence of permeability on skeleton deformation have been included. Matrix formulation of the problem has been presented from the point of view of the finite element method. An implicit iterative time integration scheme has been proposed. The algorithm has been illustrated with results of simple numerical tests.