Hydrodynamic interaction between two red blood cells in simple shear flow: its impact on the rheology of a semi-dilute suspension
Hydrodynamic interaction between two red blood cells in simple shear flow: its impact on the rheology of a semi-dilute suspension
复制标题
简单剪切流中两个红细胞之间的流体动力学相互作用：其对半稀释悬浮液流变学的影响
DOI：
10.1007/s00466-014-0997-1
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发表时间：
2014
影响因子：
4.1
通讯作者：
T.
中科院分区：
文献类型：
--
作者：
Omori;T.;Ishikawa;T.;Imai;Y.;Yamaguchi;T.
血液是红细胞（rbc）的悬浮液，其流变学在讨论心血管系统的生理学时很重要。在这项研究中，我们对红细胞悬浮液从稀释到半稀释的流变性能进行了数值研究。红细胞被建模成一个带有二维超弹性膜的胶囊。用有限元法计算了薄膜的大变形。由于红细胞体积小，假设红细胞周围的流体运动遵循Stokes流，并采用边界元法求解。在稀释极限下，忽略细胞间的相互作用，并通过单个红细胞上产生的应力计算悬浮液的体积应力。有趣的是，随着内液粘度的增加，稀悬液的有效剪切粘度减小。在半稀释状态下，细胞可以被认为显示成对相互作用。半稀悬浮液的有效剪切粘度随体积分数呈二次型增长。这些发现对于理解血液流变学的复杂现象具有重要意义。
Blood is a suspension of red blood cells (RBCs) and its rheology is important when discussing the physiology of the cardiovascular system. In this study, we performed a numerical investigation of the rheological properties of an RBC suspension from the dilute to semi-dilute regime. RBCs were modelled as a capsule with a two-dimensional hyperelastic membrane. Large deformation of the thin membrane was calculated by a finite element method. Due to the small size of the RBC, fluid motion around the RBC was assumed to follow Stokes flow and was solved by a boundary element method. In the dilute limit, cell–cell interactions were omitted and the bulk stress of the suspension was calculated by the stresslet generated on a single RBC. Interestingly, the effective shear viscosity of the dilute suspension decreased with increasing viscosity of the internal liquid. In the semi-dilute regime, cells can be considered as showing pairwise interactions. The effective shear viscosity of the semi-dilute suspension shows a quadratic increase with respect to the volume fraction. These findings are important for understanding the complex phenomena of blood rheology.