An efficient immersed boundary-lattice Boltzmann method for the hydrodynamic interaction of elastic filaments

JOURNAL OF COMPUTATIONAL PHYSICS

卷:230

Article

Tian, Fang-Bao^1,2  Luo, Haoxiang²  Zhu, Luoding³  Liao, James C.⁴  Lu, Xi-Yun¹ 

[1] Univ Sci & Technol China, Dept Modern Mech, Hefei 230026, Anhui, Peoples R China

[2] Vanderbilt Univ, Dept Mech Engn, Nashville, TN 37235 USA

[3] Indiana Univ Purdue Univ, Dept Math Sci, Indianapolis, IN 46202 USA

[4] Univ Florida, Dept Biol, Whitney Lab Marine Biosci, St Augustine, FL 32080 USA

关键词: Flow-structure interaction;    Immersed boundary method;    Lattice Boltzmann method;    Fish swimming;    Flapping flags;   

DOI  :  10.1016/j.jcp.2011.05.028

来源: Elsevier

【 摘 要 】

We have introduced a modified penalty approach into the flow-structure interaction solver that combines an immersed boundary method (IBM) and a multi-block lattice Boltzmann method (LBM) to model an incompressible flow and elastic boundaries with finite mass. The effect of the solid structure is handled by the IBM in which the stress exerted by the structure on the fluid is spread onto the collocated grid points near the boundary. The fluid motion is obtained by solving the discrete lattice Boltzmann equation. The inertial force of the thin solid structure is incorporated by connecting this structure through virtual springs to a ghost structure with the equivalent mass. This treatment ameliorates the numerical instability issue encountered in this type of problems. Thanks to the superior efficiency of the IBM and LBM, the overall method is extremely fast for a class of flow-structure interaction problems where details of flow patterns need to be resolved. Numerical examples, including those involving multiple solid bodies, are presented to verify the method and illustrate its efficiency. As an application of the present method, an elastic filament flapping in the Karman gait and the entrainment regions near a cylinder is studied to model fish swimming in these regions. Significant drag reduction is found for the filament, and the result is consistent with the metabolic cost measured experimentally for the live fish. (C) 2011 Elsevier Inc. All rights reserved.

【 授权许可】

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