基于有限元模拟的支架扩张、血流动力学及支架疲劳分析  

Analysis of stent expansion,blood flow and fatigue life based on finite element method

作　　者：李红霞[1] 张艺浩[1] 王希诚[1] 

机构地区：[1]大连理工大学运载工程与力学学部工业装备结构分析国家重点实验室,大连116024

出　　处：《医用生物力学》2012年第2期178-185,共8页Journal of Medical Biomechanics

基　　金：国家自然科学基金资助项目(11072048);国家重点基础研究发展计划973项目基金(2009CB918501)

摘　　要：目的利用有限元方法研究支架在狭窄血管内的扩张性能、支架内血流动力学状况和支架的疲劳寿命。方法采用ANSYS模拟支架在狭窄血管内的扩张过程,提取扩张后相关节点数据,建立血流动力学分析模型,并建立与之对应的简化模型,模拟分析支架内血流动力学状况。分别基于Goodman图表和累计损伤法,对支架的疲劳寿命进行评估。结果 (1)支架上绝大部分部位发生塑性变形,主要应力发生在镂空孔的角点。(2)支架附近流动紊乱,血流流入端的桥接支柱附近应力最高。(3)Goodman图表法表明该支架是安全的,累计损伤法表面支架在血流流入端桥接支柱所在的第2个横截面上累计损伤最大。结论有限元方法能有效地应用于支架扩张、支架内血流动力学以及支架的疲劳模拟仿真。Objective To study the expansion behavior of stent in stenotic vascular,in-stent blood flow and fatigue life of stent by finite element method.Methods ANSYS was used to simulate the expansion of stent in stenotic vascular.The blood flow model was created by constructing the entities based on deformation of the related nodes from the result of dilation process.A sample model was also built to simulate the in-stent blood flow.Stent fatigue life was evaluated based on Goodman＇s method and accumulated damage method,respectively.Results（1） Plastic deformation appeared on most parts of struts.The major stresses were localized in the corner of the slots.（2） Turbulent flow occured near the stent.Stresses of stent in cross-section of bridge struts along the direction of blood flow were highest.（3） Goodman＇s method showed that the stent was safe,and cumulative damage indicated that the largest cumulative damage occured in the second cross-section of bridge struts.Conclusions Finite element method can be effectively used to simulate the stent expansion,in-stent blood flow and stent fatigue life.

关 键 词：支架 有限元分析 扩张性能 血流动力学 疲劳寿命 变形 

分 类 号：R318.01[医药卫生—生物医学工程]