A coupled momentum method for modeling blood flow in three-dimensional deformable arteries
A coupled momentum method for modeling blood flow in three-dimensional deformable arteries
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DOI：
10.1016/j.cma.2005.11.011
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发表时间：
2006-01-01
影响因子：
7.2
通讯作者：
Taylor, Charles A.
中科院分区：
文献类型：
--
作者：
Figueroa, C. Alberto;Vignon-Clementel, Irene E.;Taylor, Charles A.
血管的变形性对大动脉内的血流速度和压力场有很大的影响。此外，由于血液通常被描述为不可压缩的流体，因此心血管系统中的波传播现象只能考虑到壁的变形能力来描述。然而，在动脉的三维模型中模拟血流的计算方法要么考虑了血管的刚性壁假设，要么考虑了显著简化或减少的几何形状。在大型、逼真的心血管系统解剖和生理模型中，使用标准的方法(如ALE方法)计算可变形区域中的血流仍然是一个棘手的问题。该方法耦合了变分水平上的管壁变形方程作为流体域的边界条件。我们考虑流体和固体域的自由度的强耦合，以及管壁的线性膜模型(通过横向剪切增强)。因此，管壁边界的影响被以整体的方式添加到流体方程中，从而产生了一个非常健壮的方案。文中给出了该方法的数学形式，并讨论了流固耦合、膜形式、时间积分法、边界条件和初始条件等问题。讨论了实现方法，并给出了简单几何模型和大型特定主题模型的结果。(C)2006爱思唯尔B.V.保留所有权利。
Blood velocity and pressure fields in large arteries are greatly influenced by the deformability of the vessel. Moreover, wave propagation phenomena in the cardiovascular system can only be described considering wall deformability since blood is usually described as an incompressible fluid. However, computational methods for simulating blood flow in three-dimensional models of arteries have either considered a rigid wall assumption for the vessel or significantly simplified or reduced geometries. Computing blood flow in deformable domains using standard techniques like the ALE method remains a formidable problem for large, realistic anatomic and physiologic models of the cardiovascular system.We have developed a new method to simulate blood flow in three-dimensional deformable models of arteries. The method couples the equations of the deformation of the vessel wall at the variational level as a boundary condition for the fluid domain. We consider a strong coupling of the degrees-of-freedom of the fluid and the solid domains, and a linear membrane model (enhanced with transverse shear) for the vessel wall. The effect of the vessel wall boundary is therefore added in a monolithic way to the fluid equations, resulting in a remarkably robust scheme. We present here the mathematical formulation of the method and discuss issues related to the fluid-solid coupling, membrane formulation, time integration method, and boundary and initial conditions. Implementation is discussed and results with simple geometries as well as large subject-specific models are presented. (c) 2006 Elsevier B.V. All rights reserved.