A nonlinear anisotropic model for porcine aortic heart valves
A nonlinear anisotropic model for porcine aortic heart valves
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DOI：
10.1016/s0021-9290(01)00092-6
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发表时间：
2001-10-01
影响因子：
2.4
通讯作者：
Kuang, ZB
中科院分区：
文献类型：
--
作者：
Li, J;Luo, XY;Kuang, ZB
然而，猪主动脉瓣叶的各向异性对其机械行为和失效机制具有潜在的显着影响。由于其复杂性，各向异性猪主动脉瓣的测试和建模迄今为止仍然是一个持续的挑战。本研究开发了猪心脏瓣膜的非线性各向异性有限元模型。该模型基于猪主动脉心脏瓣叶的单轴实验数据和非线性复合材料的性能。开发了有限元代码来使用 8 节点超参数非线性壳和更新拉格朗日方法来解决该问题。计算了均匀厚度和非均匀厚度的猪主动脉瓣在闭合相和加载状态下的应力分布和变形。结果表明，由于小叶的各向异性，应力分布发生了显着变化。与相同负载条件下的各向同性阀门相比。结果发现，各向异性小叶的峰值应力位置不同，最大纵向正应力增大，但最大横向正应力和面内剪应力减小。我们的结论是，考虑猪心脏瓣膜的各向异性特性对于了解此类瓣膜在体内的失效机制非常重要。 (C) 2001 Elsevier Science Ltd，保留所有权利。
The anisotropic property of porcine aortic valve leaflet has potentially significant effects on its mechanical behaviour and the failure mechanisms, However. due to its complex nature, testing and modelling the anisotropic porcine aortic valves remains a continuing challenge to date. This study has developed a nonlinear anisotropic finite element model for porcine heart valves. The model is based on the uniaxial experimental data of porcine aortic heart valve leaflet and the properties of nonlinear composite material. A finite element code is developed to solve this problem using the 8-node super-parameter nonlinear shells and the update Lagrangian method. The stress distribution and deformation of the porcine aortic valves with either uniform and non-uniform thicknesses in closed phase and loaded condition are calculated. The results showed significant changes in the stress distributions due to the anisotropic property of the leaflets. Compared with the isotropic valve at the same loading condition. it is found that the site of the peak stress of the anisotropic leaflet is different, the maximum longitudinal normal stress is increased, but the maximum transversal normal stress and in-plane shear stress are reduced. We conclude that it is very important to consider the anisotropic property of the porcine heart valves in order to understand the failure mechanism of such valves in vivo. (C) 2001 Elsevier Science Ltd, All rights reserved.