Numerical study of 3D vesicles under flow: discovery of new peculiar behaviors

Abstract

The study of vesicles under flow, a model system for red blood cells (RBCs), is an essential step in understanding various intricate dynamics exhibited by RBCs in vivo and in vitro. Quantitative 3D analyses of vesicles under flow are presented. The regions of parameters to produce tumbling (TB), tank-treating (TT), vacillating-breathing (VB) {and even Kayaking (K)} modes are determined. New qualitative features are found: (i) a significant widening of the VB mode region in parameter space upon increasing shear rate $\dot\gamma$ and (ii) a striking robustness of period of TB and VB with $\dot\gamma$. Analytical support is also provided. These findings shed new light on the dynamics of blood flow.