RBC Distribution in Stenosed Arterial Geometries Using Hematocrit Dependent Viscosity Model (HDVM)

Human blood is a concentrated suspension of mainly red blood cells (RBCs) in plasma and exhibits some non-Newtonian behavior at low shear rates. Traditionally, computational simulations have employed non-Newtonian viscosity models, such as the power-law, Casson, or Quemada model, which are a function of the local shear rate and depend on two to four constant parameters, including the hematocrit. In this study the non-Newtonian behavior of the blood viscosity is expressed as a function of the hematocrit. Specifically, a convection-diffusion equation for the RBCs has been solved, integrated into an apparent viscosity model, and applied to blood flow in a stenosed arterial segment. The computational results provide detailed information of non-Newtonian flow characteristics including distributions of the local hematocrit as well as near-wall hematocrit, shear rate, and viscosity. The new model can be used for more realistic hemodynamics simulations, including calculations of comprehensive physico-biological indicators of sites susceptible to the onset and progression of arterial diseases.