Membrane-enclosed fluid objects, or capsules, are everywhere in natural and industrial processes, from red blood cells and circulating tumor cells in the life sciences to encapsulated substances in the pharmaceutical, food and cosmetic industries. A non-destructive way to achieve size- and deformability-based segregation of suspended capsules is to exploit flow features in order to lock a given type of capsules on a specific trajectory, as done in inertial microfluidic devices. In this talk, I will present a numerical method able to simulate flowing capsules on adaptive octree grids, allowing to consider very large and complex computational domains. A finite element method and a paraboloid fitting technique are used to compute the elastic and the high-order bending stresses on the membrane surface, and the capsule and the fluid problem are coupled using an immersed boundary method. After presenting the governing equations and our numerical implementation, we discuss the wide range of applications that this adaptive solver allows to investigate, in particular in the realm of inertial microfluidics.

Pizza lunch will be served.

We gratefully acknowledge generous financial support by the Pacific Institute for the Mathematical Sciences (PIMS) and the Institute of Applied Mathematics (IAM).