流动槽中内皮细胞表面切应力分布的数值模拟

Simulation of Endothelial Cell Behavior by 2 D Steady Flow on Wavy Surface

对流动槽中经过不同入口流速冲刷稳定后的ＥＣ（内皮细胞）表面的切应力分布进行数值模拟，视单个ＥＣ为一条二次曲线，多个ＥＣ的连续分布为此二次曲线的周期拓延，随流速的增加．ＥＣ有沿动流动方向的伸长及细胞质沿流动方向的前移．结果表明：切应力随ＥＣ的形状呈现相同周期性分布的特点，随着单个ＥＣ的Ｒ（高／长）值的增加，切应力呈现上升的趋势；对相同的Ｒ值，迎来流面的切应力值大于背来流面的值．这一研究结果对于了解ＥＣ发生的物理、生理、、生化及基因重组等复杂反应从一个方面提供了有价值的知识．

Shear stress acting on the endothelium suggests the involvement of physical、physiological 、biochemical and gene regulatory reaction. They depend on the magnitude and gradient of the shear stress. The geometry of cell membrane effects the distribution and gradient of the shear stress. A 2 D steady laminar flow over a wavy surface that approximates a monolayer of endothelial cells is used in the numerical simulation. The shape of a single cell was chosen as a quadratic curve, while cells in a row could be regarded as the periodic extension of the quadratic curve. As a result, the wall shear stress distribution has the same periodicity as the wavy wall surface depending on the aspect ration R , i. e., height/length. The shear stress increases with R . For the same R value, the magnitude of the stress on the surface that facing the flow is larger than that at the back of the flow.