Model of blood rheology including hemolysis based on population balance

Abstract

This study aimed to develop a universal rheological blood model that reflects physiological processes related to blood in any blood vessel. Blood is a multicomponent fluid and its rheology depends on various factors, such as concentration of red blood cells and local shear stresses. However, existing rheology models cannot be used for all flows and geometries. The population balance blood rheology model proposed in this study mimics the natural mechanisms of red blood cell agglomeration and deagglomeration using the quadrature methods of moments implemented in computational fluid dynamics codes. In addition, it can model hemolysis flows observed in arteries with atherosclerotic changes in an in vivo environment. The new model is also useful in modeling local viscosity in arteries with stenosis and hemolysis, owing to only single red blood cells being hemolyzed. The geometries used for calculations were simplified models of the arteries observed during medical procedures. The results demonstrated that the model correctly predicted the uneven distribution of red blood cell agglomerates across arteries. Furthermore, the presented model predicted a smoother transition between high and low viscosity zones before and after stenosis, respectively, compared to the characteristic viscosity of the Carreau Yasuda model for viscosimetric conditions. Furthermore. the proposed model can predict the concentration of deagglomerated single red blood cells and the size of red blood cell agglomerates, which influences blood rheology and hemolysis.