標題: | An immersed boundary method for simulating vesicle dynamics in three dimensions |
作者: | Seol, Yunchang Hu, Wei-Fan Kim, Yongsam Lai, Ming-Chih 應用數學系 數學建模與科學計算所(含中心) Department of Applied Mathematics Graduate Program of Mathematical Modeling and Scientific Computing, Department of Applied Mathematics |
關鍵字: | Immersed boundary method;Incompressible membrane;Three-dimensional vesicle;Navier-Stokes equations |
公開日期: | 1-十月-2016 |
摘要: | We extend our previous immersed boundary (IB) method for 3D axisymmetric inextensible vesicle in Navier-Stokes flows (Hu et al., 2014 [17]) to general three dimensions. Despite a similar spirit in numerical algorithms to the axisymmetric case, the fully 3D numerical implementation is much more complicated and is far from straightforward. A vesicle membrane surface is known to be incompressible and exhibits bending resistance. As in 3D axisymmetric case, instead of keeping the vesicle locally incompressible, we adopt a modified elastic tension energy to make the vesicle surface patch nearly incompressible so that solving the unknown tension (Lagrange multiplier for the incompressible constraint) can be avoided. Nevertheless, the new elastic force derived from the modified tension energy has exactly the same mathematical form as the original one except the different definitions of tension. The vesicle surface is discretized on a triangular mesh where the elastic tension and bending force are calculated on each vertex (Lagrangian marker in the IB method) of the triangulation. A series of numerical tests on the present scheme are conducted to illustrate the robustness and applicability of the method. We perform the convergence study for the immersed boundary forces and the fluid velocity field. We then study the vesicle dynamics in various flows such as quiescent, simple shear, and gravitational flows. Our numerical results show good agreements with those obtained in previous theoretical, experimental and numerical studies. (C) 2016 Elsevier Inc. All rights reserved. |
URI: | http://dx.doi.org/10.1016/j.jcp.2016.06.035 http://hdl.handle.net/11536/134220 |
ISSN: | 0021-9991 |
DOI: | 10.1016/j.jcp.2016.06.035 |
期刊: | JOURNAL OF COMPUTATIONAL PHYSICS |
Volume: | 322 |
起始頁: | 125 |
結束頁: | 141 |
顯示於類別: | 期刊論文 |