轴对称有狭窄弹性管流固耦合模型及数值模拟

建立了求解厚壁，有狭窄，大管壁变形的血管及管内血液流动的流固耦合问题的数值计算模型。血管的几何形状、物质特性及模型的有关物理参数由模拟颈动脉血流及血管壁塌陷的实验获得。流体采用Ｎａｖｉｅｒ－Ｓｔｏｋｅｓ方程，用广义有限差分方法求解。

AXISYMMETRIC MODEL AND NUMERICAL METHOD FOR STENOTIC ELASTIC TUBE WITH FLUID-WALL INTERACTIONS

A computational thick wall model with fluid wall interactions is introduced to investigate viscous flow in stenotic elastic tubes with large wall deformation and stress strain distributions in the tube wall. Navier Stokes equations are used as governing equations for the fluid and solved using a Generalized Finite Difference method. A thick wall model is introduced for the elastic tube and solved by a finite element method. The ranges of physical parameters and geometries of the tube and fluid domain are chosen to match an experimental set up simulating artery collapse and blood flow in carotid arteries with stenoses. The mechanical properties of the tube wall are measured experimentally and used in the model. Use of generalized finite differences and an incremental iteration technique makes it possible to derive finite difference schemes using arbitrary grid points and handle the fluid wall interactions. The results show that severe stenoses lead to wall compression and critical flow conditions such as negative pressure and high shear stress which may be related to artery collapse and plaque cap rupture which lead directly to heart attack and stroke. Computational and experimental results are compared and reasonable agreement is found.