FLUID-STRUCTURE INTERACTION ANALYSIS OF WALL STRESS AND FLOW PATTERNS IN A THORACIC AORTIC ANEURYSM
FLUID-STRUCTURE INTERACTION ANALYSIS OF WALL STRESS AND FLOW PATTERNS IN A THORACIC AORTIC ANEURYSM
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DOI：
10.1142/s1758825109000095
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发表时间：
2009-03-01
影响因子：
3.5
通讯作者：
Xu, X. Y.
中科院分区：
文献类型：
--
作者：
Tan, F. P. P.;Torii, R.;Xu, X. Y.
在这项研究中，流体-结构相互作用（FSI）模拟进行预测壁切应力（WSS）和血流模式在胸主动脉瘤（TAA）的血液动力学应力对患病的主动脉壁被认为是导致动脉瘤的生长，进展和破裂。基于MR图像，重建患者特定的TAA模型。采用了一种新开发的两方程层流-湍流转捩模型，并采用真实的速度和压力波形作为边界条件。分析结果包括湍流强度，壁面位移，WSS，壁面拉应力和速度剖面之间的比较MRI数据，刚性和FSI模拟。速度分布表明，FSI模拟与MRI数据有更好的一致性，而时间平均WSS（TAWSS）和振荡剪切指数（OSI）分布的结果显示模拟之间没有定性差异。与FSI模型相比，最大TAWSS值降低了13%，而湍流强度显著高于刚性模型。FSI模拟还提供了根据von Mises应力的壁机械应力的结果，从而可以识别高壁应力区域。
In this study, fluid-structure interaction (FSI) simulation was carried out to predict wall shear stress (WSS) and blood flow patterns in a thoracic aortic aneurysm (TAA) where haemodynamic stresses on the diseased aortic wall are thought to lead to the growth, progression and rupture of the aneurysm. Based on MR images, a patient-specific TAA model was reconstructed. A newly developed two-equation laminar-turbulent transitional model was employed and realistic velocity and pressure waveforms were used as boundary conditions. Analysis of results include turbulence intensity, wall displacement, WSS, wall tensile stress and comparison of velocity profiles between MRI data, rigid and FSI simulations. Velocity profiles demonstrated that the FSI simulation gave better agreement with the MRI data while results for the time-averaged WSS (TAWSS) and oscillatory shear index (OSI) distributions showed no qualitative differences between the simulations. With the FSI model, the maximum TAWSS value was 13% lower, whereas the turbulence intensity was significantly higher than the rigid model. The FSI simulation also provided results for wall mechanical stress in terms of von Mises stress, allowing regions of high wall stress to be identified.