Numerical analysis of flow through a severely stenotic carotid artery bifurcation
Numerical analysis of flow through a severely stenotic carotid artery bifurcation
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DOI：
10.1115/1.1427042
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发表时间：
2002-02-01
影响因子：
1.7
通讯作者：
Saloner, D
中科院分区：
文献类型：
--
作者：
Stroud, JS;Berger, SA;Saloner, D
计算模拟的结果可以补充MR和其他体内诊断技术，以提供特定血管中血液动力学的所有准确图像，这可以帮助证明由特定斑块沉积物引起的栓塞或斑块破裂的风险。在这项研究中，一个模型的基础上所有的动脉内膜切除标本的斑块在颈动脉分叉进行了检查。流动条件包括雷诺数为300、600和900时的稳定流动以及非稳定脉动流动。动压和壁面剪切应力都非常高，剪切值高达70 N/m（2），靠近颈内动脉狭窄的喉部，并且两者在流动循环中变化显著。沿喉道沿着壁面剪应力梯度也很大。在最严重闭塞的下游观察到旋涡脱落。两个湍流模型，钱和Goldberg品种的k-ε，测试和评估其相关性，在这种几何形状。Chien模型更好地捕捉了旋涡脱落等现象。狭窄远端的流动可能是过渡性的，因此需要一个能够捕获层流和湍流行为的模型。
The results of computational simulations may supplement MR and other in vivo diagnostic techniques to provide all accurate picture of the hemodynamics in particular vessels, which may help demonstrate the risks of embolism or plaque rupture posed by particular plaque deposits. In this study, a model based on all endarterectomy specimen of the plaque in a carotid bifurcation was examined. The flow conditions include steady flow at Reynolds numbers of 300, 600, and 900 as well as unsteady, pulsatile flow. Both dynamic pressure and wall shear stress are very, high, with shear values up to 70 N/m(2), proximal to the stenosis throat in the internal carotid artery, and both vary significantly through the flow cycle. The wall shear stress gradient is also strong along the throat. Vortex shedding is observed downstream of the most severe occlusion. Two turbulence models, the Chien and Goldberg varieties of k-epsilon, are tested and evaluated for their relevance in this geometry . The Chien model better captures phenomena such as vortex shedding. The flow distal to stenosis is likely transitional, so a model that captures both laminar and turbulent behavior is needed.