半圆形截面血管内支架结构流阻的数值模拟实验

通过SoildWorks软件构建血液流场和8种不同结构裸支架(支架形状和通透率不同)的三维实体模型.利用计算流体力学方法,借助于有限元软件ANSYS 11.0对不同结构内支架分别置入血管后进行仿真研究.一定通透率范围内,对于半圆形截面支架模型血液从半圆面流向平面时的流阻大于反向流过时的流阻;通透率大到一定值时,结果相反.无论是网格状支架模型还是正弦状支架模型,血液从支架正反两个方向流过时的流阻大小随通透率的增加而减小;相同通透率下,血液从相同方向流过支架时,网格状支架模型的流阻比正弦状支架模型的大一些,大概在1.5倍左右.结果提示,血液从不同方向流过半圆形支架丝时的流阻存在一定的差异,这为支架结构设计提供了重要的理论指导意义.

Numerical simulation of semi-circular section stent grafts

Geometrically virtual models of three-dimensional blood flow field and eight types of mesh stent (different porosity and different stent shape) were constructed using SoildWorks software, and simulation of stented models were performed respectively using finite element software ANSYS11.0 according to computation fluid dynamics method. The flow resistance of the semi-circular section stent model of blood flow from the semi-circular planar surface was greater than the reverse in a certain range of permeability. However, the result was the opposite when the porosity increased to a specific value. For both grid-stent model and sine-stent model, flow resistance of blood that flowed from the stent in both directions increased with the porosity reduction. Under the same porosity and the direction of blood flow from the same stent, the flow resistance of the grid stent model was 1.5 times greater than the sine-stent model. Results showed that there are different effects on the flow resistance in blood flow in different directions from the semi-circular section stent model.