采用浸入式边界法,模拟了多个红细胞和血小板在毛细血管内流动过程中的相互影响.通过改变红细胞体积比和红细胞的力学特性,分析了红细胞力学特性对血小板在与内皮细胞发生粘附前的动力学行为的影响机理,包括:红细胞对血小板趋壁效应的影响,血小板在流动过程中的变形情况,并从血小板所受垂直壁向合力的角度深入研究了红细胞和血小板之间的相互作用.数值模拟的结果表明,增加血流中的红细胞体积比,减小了血小板和血管壁之间的距离,增大了血小板的变形,血小板所受垂直壁向合力呈现剧烈波动,两者之间的挤压显著加强;而增大红细胞硬度,使得血小板的离壁距离增大.
The effect of erythrocyte mechanical properties on the near-wall motion of platelet was numerically studied with the immersed boundary method. Cells were modeled as viscous-fluid-filled capsules surrounded by a hyper-elastic membrane with negligible thickness. The numerical results show that with the increase in hematocrit, the near-wall approaching is enhanced; platelet exhibits larger deformation and orientation (angle of its near-wall tank-treading motion); the lateral force pushing platelet to the wall is increased with larger fluctuation amplitude of lateral force, while the near- wall approaching is reduced by increasing the stiffness of erythrocytes.