The inertial migration of a three-dimensional (3D) elastic capsule in a plane Poiseuille flow has been simulated by using the penalty immersed boundary method. An improved front-tracking method was developed to take into account the difference between the viscosities of the interior and exterior fluids. The calculation domain was confined to the capsule boundary by employing the ray casting algorithm. The dynamic motions and the lateral equilibrium positions of the elastic capsules in moderate Reynolds number (Re) flows were examined as functions of the initial lateral position (y0), Re, the aspect ratio (ε), the viscosity ratio (λ), the membrane stretching coefficient (ϕ), the bending coefficient (γ) and the initial roll angle (θx). Three dynamical motions were observed: tank-treading, swinging and tumbling. The initial behavior of the capsule is influenced by the initial lateral position (y0), but the equilibrium position of the capsule is not affected by variation in y0. The equilibrium position is determined by the balance between the wall effect and the shear gradient effect.
|Original language||English (US)|
|Number of pages||10|
|Journal||International Journal of Heat and Fluid Flow|
|State||Published - Aug 1 2015|
Bibliographical noteFunding Information:
This study was supported by the Creative Research Initiatives (No. 2015-001828) program of the National Research Foundation of Korea (MSIP).
- Capsule migration
- Front-tracking method
- Lateral position
- Penalty immersed boundary method