A reduced-order model for red blood cell dynamics in blood flow

Understanding blood rheology plays an essential role in developing new bio-microfluidic systems. Modelling the dynamic behavior of biological cells in blood flow such as red blood cell (RBC) has been a challenge in the past decades due to their complex physics. Several computational methods have been developed to model RBC dynamics but they mostly entail high computational costs. In the present study, we propose a reduced-order model to overcome this limitation by representing RBC as an arrangement of bonded spheres in interaction with the surrounding fluid. The model is implemented in the framework of resolved CFD-DEM. A micro-channel full of suspended RBCs in blood plasma corresponding to hematocrits of 0.15, 0.3 and 0.45 was simulated. The dynamic behavior of RBCs such as deformation, tumbling and etc, as well as the formation of the cell free layer near the channel wall and the velocity are investigated. Accordingly, the change in the apparent viscosity of whole blood is analyzed showing a good agreement with previous literature.