中文摘要：

临床并且柱子打死他们研究显示在人，颈动脉动脉分叉的颈动脉湾穴是为动脉粥样硬化患者损害的开始和发展的赞成地点之一。血液动力学的因素被建议了在 atherogenesis 重要。在颈动脉湾穴理解在 atherogenesis 和液体动力学之间的关联，在动脉的血流动数字地被模仿。在那些研究，血的性质被当作不可压缩的、牛顿的液体。事实上然而，血是复杂非牛顿的液体与砍变瘦并且粘弹性的性质，特别当 shear 率是低的时。许多非牛顿的模型在数字研究被使用了。在他们之中， Casson 方程广泛地被使用。然而，仅仅当 shear 率是不到 10 s ⁻¹ 时， Casson 方程同意很好。颈动脉分叉的流动领域通常盖住大量 shear 率。我们因此相信描述仅仅在颈动脉分叉的整个流动领域里使用 Casson 方程的血的性质不能是足够的。在现在的学习，三不同的血组成的模型，也就是牛顿， Casson 和混合液体组成的模型在人的颈动脉分叉的流动模拟被使用。结果在三个模型之中被比较。结果证明牛顿的模型和混血儿为轴的速度，第二等的流动和墙的有的很类似的分布建模砍应力，而是 Casson 模型从另外的二个模型在这些分布导致了重要差别。这研究建议仅仅使用 Casson 方程模仿颈动脉分叉的整个流动领域不是适当的，并且在另一方面，牛顿的液体是到为在颈动脉动脉分叉的流动模拟的血的好近似。

英文摘要：

Both clinical and post mortem studies indicate that, in humans, the carotid sinus of the carotid artery bifurcation is one of the favored sites for the genesis and development of atherosclerotic lesions. Hemodynamic factors have been suggested to be important in atherogenesis. To understand the correlation between atherogenesis and fluid dynamics in the carotid sinus, the blood flow in artery was simulated numerically. In those studies, the property of blood was treated as an incompressible, Newtonian fluid. In fact, however, the blood is a complicated non-Newtonian fluid with shear thinning and viscoelastic properties, especially when the shear rate is low. A variety of non-Newtonian models have been applied in the numerical studies. Among them, the Casson equation was widely used. However, the Casson equation agrees well only when the shear rate is less than 10 s-1. The flow field of the carotid bifurcation usually covers a wide range of shear rate. We therefore believe that it may not be sufficient to describe the property of blood only using the Casson equation in the whole flow field of the carotid bifurcation. In the present study, three different blood constitutive models, namely, the Newtonian, the Casson and the hybrid fluid constitutive models were used in the flow simulation of the human carotid bifurcation. The results were compared among the three models. The results showed that the Newtonian model and the hybrid model had verysimilar distributions of the axial velocity, secondary flow and wall shear stress, but the Casson model resulted in significant differences in these distributions from the other two models. This study suggests that it is not appropriate to only use the Casson equation to simulate the whole flow field of the carotid bifurcation, and on the other hand, Newtonian fluid is a good approximation to blood for flow simulations in the carotid artery bifurcation.