(142cl) Capsule Motion in Constricted Microchannels

The study of the interfacial dynamics of artificial or physiological capsules (i.e. membrane-enclosed fluid volumes) in Stokes flows has seen an increased interest during the last few decades due to their numerous industrial, biological and physiological applications.

In this study, we investigate the motion of capsules in a microfluidic channel with a rectangular constriction by employing our three-dimensional Interracial Spectral Boundary Element method for elastic capsules. In particular, we study strain-hardening capsules with comparable shearing and area-dilatation resistance.

In our talk we will present the effects of capsule size and flow rate on the capsule dynamics in the confined solid geometries. As the channel s flow rate increases or the capsule size increases (i.e. higher hydrodynamic forces), the capsule deformation increases. In addition, as the capsule size increases, its velocity decreases while the additional pressure difference increases significantly, owing to the smaller lubrication gap between the capsule surface and the solid walls.