Validated computation of physiologic flow in a realistic coronary artery branch
Validated computation of physiologic flow in a realistic coronary artery branch
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DOI：
10.1016/s0021-9290(97)00118-8
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发表时间：
1998-03-01
影响因子：
2.4
通讯作者：
Friedman, MH
中科院分区：
文献类型：
--
作者：
Perktold, K;Hofer, M;Friedman, MH
对冠状动脉左前降支（LAD）分叉及其第一对角分支（D1）的脉动流场进行了数值模拟和激光多普勒测量。在计算机模拟和物理实验中使用的入口速度分布是生理上真实的。计算几何模型是在数字化动脉模型的基础上开发的。LAD在心脏表面上的曲率导致轴向速度曲线略微偏向心外膜壁。在分叉的下游，由于分支，朝向分流器壁发生强烈的偏斜。在局部，由复二次速度引起的壁面剪应力分量可与轴向分量一样高。从细胞为基础的角度来看，壁面剪应力表示表现出低的剪切应力和大的偏离收缩期的时间平均剪切应力方向。在孔隙中，瞬时壁面剪应力方向与平均方向基本一致。轴向速度的计算结果和测量结果的比较表明，一般良好的协议。与从圆柱形管构造的更简单的几何形状中的计算流模式相比，流场被发现是更平滑的，大概反映了血管轮廓对所包含的流的适应。(C)1998爱思唯尔科技有限公司版权所有。
The pulsatile flow field in an anatomically realistic model of the bifurcation of the left anterior descending coronary artery (LAD) and its first diagonal branch (D1) was simulated numerically and measured by laser Doppler anemometry. The inlet velocity profiles used in the computer simulation and in the physical experiments were physiologically realistic. The computational geometric model was developed on the basis of a digitized arterial cast. The curvature of the LAD over the cardiac surface leads to axial velocity profiles which are slightly skewed towards the epicardial wall. Downstream of the bifurcation, a strong skewing occurs towards the flow divider walls as a result of branching. Locally, the wall shear stress component caused by the complex secondary velocity can be as high as the axial component. The wall shear stress representation from a cell-based perspective exhibits low shear stress and large deviation from the time-averaged shear stress direction during systole. In diastole, the instantaneous wall shear stress direction nearly corresponds to the mean direction. The comparison of computed and measured axial velocity results shows generally good agreement. In contrast to computed flow patterns in simpler geometries constructed from cylindrical tubes, the flow field is found to be smoother, presumably reflecting the adaptation of the vascular contour to the contained flow. (C) 1998 Elsevier Science Ltd. All rights reserved.