Department of Chemical and Biological Engineering, University of Wisconsin-Madison, Madison, Wisconsin 53706, USA.
Phys Rev Lett. 2012 Sep 7;109(10):108102. doi: 10.1103/PhysRevLett.109.108102. Epub 2012 Sep 4.
Flowing blood displays a phenomenon called margination, in which leukocytes and platelets are preferentially found near blood vessel walls, while erythrocytes are depleted from these regions. Here margination is investigated using direct hydrodynamic simulations of a binary suspension of stiff (s) and floppy (f) capsules, as well as a stochastic model that incorporates the key particle transport mechanisms in suspensions-wall-induced hydrodynamic migration and shear-induced pair collisions. The stochastic model allows the relative importance of these two mechanisms to be directly evaluated and thereby indicates that margination, at least in the dilute case, is largely due to the differential dynamics of homogeneous (e.g. s-s) and heterogeneous (s-f) collisions.
流动的血液呈现出一种称为靠边的现象，其中白细胞和血小板优先出现在血管壁附近，而红细胞则从这些区域中耗尽。在这里，使用刚性（s）和柔软（f）胶囊的二元悬浮液的直接流体动力学模拟以及包含悬浮液-壁诱导流体动力迁移和剪切诱导对碰撞等关键颗粒输运机制的随机模型来研究靠边现象。随机模型允许直接评估这两个机制的相对重要性，从而表明靠边现象，至少在稀相情况下，主要是由于同质（例如 s-s）和异质（s-f）碰撞的不同动力学。
