中文摘要：

基于血流与血管壁间双向流固耦合作用,将血液设为两相流体,运用计算流体力学方法对左冠状动脉内血流进行瞬态数值模拟.研究了一个心动周期内典型时刻下左冠状动脉内血流分布特性,并与Newton（牛顿）血液和两相血液模型对比,分析了两相血液和流固耦合作用对血流特性的影响.结果表明,左冠状动脉左回旋支远段和钝缘支近心端外侧分布了低速涡流区,该区域内壁面切应力和红细胞体积分数均较小,为动脉粥样硬化的形成与发展提供了合适的生理环境.左冠状动脉分叉处管壁形变量较大,引起管壁内膜功能发生紊乱,促进了粥样硬化斑块的形成.3种血液模型对比可知,红细胞的流动特性对血流速度及壁面切应力等血流动力学特性影响较大,双向流固耦合模型更符合真实的血液流动情况.

英文摘要：

A Treated as a 2-phase flow, the blood flow in the left coronary artery with stenosis was transiently simulated with the method of computational fluid mechanics, under the bidirec- tional fluid-structure interaction between the blood flow and the vascular wall. The blood flow distribution characteristics in the left coronary artery was analyzed at typical moments within a cardiac cycle, and the effects of the 2-phase blood model plus the fluid-structure interaction on the hemodynamics were studied in comparison with those of the Newtonian blood model and the 2-phase blood model. The results show that, in the proximal outside of the obtuse marginal and the distal part of the left circumflex branch there appear low-speed eddy zones where both the wall shear stress and the red blood cells＇ volume fraction are relatively small, resulting in a suitable physical environment for the formation and development of atherosclerosis. The wall displacement at the left coronary artery bifurcation is rather large, making a possible cause for the disfunctions of the vascular wall intima, which also prompts the formation of the atherosclerotic plaques. The comparison between different blood models shows, the flow characteristics of red blood cells have considerable influences on the hemodynamics of blood flow velocity and wall shear stress, and the bidirectional fluid-structure interaction model is more consistent with the true situation of the blood flow.