Yung C N, De Witt K J, Keith T G
Department of Chemical Engineering, University of Toledo, Ohio 43606.
J Biomech Eng. 1990 May;112(2):189-97. doi: 10.1115/1.2891171.
Steady flow of an incompressible, Newtonian fluid through a symmetric bifurcated rigid channel was numerically analyzed by solving the three-dimensional Navier-Stokes equations. The upstream Reynolds number ranged from 100 to 1500. The bifurcation was symmetrical with a branch angle of 60 deg and the area ratio of the daughter to the mother vessel was 2.0. The numerical procedure utilized a coordinate transformation and a control volume approach to discretize the equations to finite difference form and incorporated the SIMPLE algorithm in performing the calculation. The predicted velocity pattern was in qualitative agreement with experimental measurements available in the literature. The results also showed the effect of secondary flow which can not be predicted using previous two-dimensional simulations. A region of reversed flow was observed near the outer wall of the branch except for the case of the lowest Reynolds number. Particle trajectory was examined and it was found that no fluid particles remained within the recirculation zone. The shear stress was calculated on both the inner and the outer wall of the branch. The largest wall shear stress, located in the vicinity of the apex of the branch, was of the same order of magnitude as the level that can cause damage to the vessel wall as reported in a recent study.
通过求解三维纳维-斯托克斯方程，对不可压缩牛顿流体在对称分叉刚性通道中的稳定流动进行了数值分析。上游雷诺数范围为100至1500。分叉是对称的，分支角度为60度，子血管与母血管的面积比为2.0。数值计算过程采用坐标变换和控制体积法将方程离散为有限差分形式，并在计算中采用SIMPLE算法。预测的速度模式与文献中可用的实验测量结果在定性上一致。结果还显示了二次流的影响，这是以前的二维模拟无法预测的。除了雷诺数最低的情况外，在分支外壁附近观察到一个逆流区域。研究了颗粒轨迹，发现没有流体颗粒留在再循环区内。计算了分支内壁和外壁上的剪应力。位于分支顶点附近的最大壁面剪应力与最近一项研究中报道的可能导致血管壁损伤的水平处于同一量级。
