IUTAM Symposium on Dynamics of Capsules, Vesicles and Cells in Flow Numerical methods for modeling the mechanics of flowing capsules using a front-tracking immersed boundary method

This paper aims to investigate a new modeling approach to model the membrane of capsules under flow. A front tracking immersed boundary method is used to solve the fluid-structure interactions between the membrane of the capsule and the inner and outer fluids. The usual modeling approach based on a two-dimensional finite-element formulation for the membrane is compared with a three-dimensional approach, where the thickness of the membrane is explicitely accounted for. The algorithm is validated considering the simple test case of the bending of a plate, showing that the mechanical equilibrium obtained by solving the fluidstructure interaction problem is the same as the one obtained by solving the solid mechanics equations only. Both 2D and 3D approaches are finally compared on the classical test of an initially spherical capsule in simple shear flow. It is found that both formulations provide comparable results. c2015 The Authors. Published by Elsevier B.V. Peer-review under responsibility of organizing committee of Biomechanics and Bioengineering (UMR CNRS 7338).