Chaos and spatial complexity of flowing red blood cells
The flow of red blood cells within cylindrical vessels is often complex and irregular, so long as the vessel is somewhat larger than the cells. We statistically analyze the kinematic behavior of a model of this flow, which includes full coupling between the elastic red cell membranes and surrounding viscous fluid. The flow is shown to be extremely sensitive to the initial flow configuration, the hallmark of a chaotic system and so-called Lagrangian turbulence. Phase-space reconstructions of the long-time flow data show that a low-dimensional attractor does not exist, so the observed long-time dynamics are indistinguishable from those generated by a stochastic system. Based on this stochasticity, a reduced-order Markov chain model for the dynamics is shown to quantitatively reproduce statistics of the full dynamical system.