An immersed boundary-lattice Boltzmann approach to study the dynamics of elastic membranes in viscous shear flows
An immersed boundary-lattice Boltzmann approach to study the dynamics of elastic membranes in viscous shear flows
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DOI：
10.1016/j.jocs.2014.06.006
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发表时间：
2014-09-01
影响因子：
3.3
通讯作者：
Ghoreishi, Soheila
中科院分区：
文献类型：
--
作者：
Dadvand, Abdolrahman;Baghalnezhad, Masoud;Ghoreishi, Soheila
采用浸没边界-格子Boltzmann相结合的方法模拟了弹性膜在粘性不可压缩流动中的动力学行为。采用格子Boltzmann方法求解规则欧拉网格上的流场，采用浸没边界方法将液膜相互作用与可变形浸没边界的拉格朗日表示相结合。这里使用的方法的显著特点是使用简单的Peskin的IBM和标准的LBM的组合。然而，为了得到更准确和真实的解，采用了拉格朗日点的非均匀分布和修正的Dirac Delta函数。给出了两个测试用例。在第一种情况下，我们考虑悬浮在简单剪切流中的囊泡，通常称为坦克踩踏运动。将计算结果与实验结果进行了比较，结果吻合较好。对于第二个测试案例，我们认为单个健康的(软的)和病的(硬的)红细胞悬浮在剪切流中。仿真结果表明，弹性变形对红细胞的整体运动起着重要的作用，其中弹性膜的自然状态是一个重要的考虑因素。此外，结果还证实了浸没边界和格子Boltzmann方法的结合可以模拟复杂的生物现象。(C)2014爱思唯尔B.V.保留所有权利。
A combined immersed boundary-lattice Boltzmann approach is used to simulate the dynamics of elastic membrane immersed in a viscous incompressible flow. The lattice Boltzmann method is utilized to solve the flow field on a regular Eulerian grid, while the immersed boundary method is employed to incorporate the fluid-membrane interaction with a Lagrangian representation of the deformable immersed boundary. The distinct feature of the method used here is to employ the combination of simple Peskin's IBM and standard LBM. In order to obtain more accurate and truthful solutions, however, a non-uniform distribution of Lagrangian points and a modified Dirac delta function are used. Two test cases are presented. In the first case, we consider a vesicle suspended in a simple shear flow commonly known as tank-treading motion. The computed results were compared with experiments, which showed reasonably good agreement. For the second test case, we consider individual healthy (soft) and sick (stiff) RBCs suspended in a shear flow. The simulation results demonstrated that elastic deformation plays an important role in overall RBC motions characterized as tank-treading and tumbling motions, in which the natural state of the elastic membrane is an essential consideration. In addition, the results confirm that the combination of the immersed boundary and lattice Boltzmann methods permits the simulation of the complex biological phenomena. (C) 2014 Elsevier B.V. All rights reserved.