Computational fluid dynamic study on effect of Carreau-Yasuda and Newtonian blood viscosity models on hemodynamic parameters

Pulsatile blood flow through the human carotid artery is studied using Computational Fluid Dynamics (CFD) in order to investigate the effect of blood rheology on the hemodynamic parameters. The carotid artery model used is segmented and reconstructed from the Magnetic Resonance Images (MRI) of a specific patient. The results of a non-Newtonian (Carreau-Yasuda) model and a Newtonian model are studied and compared. The results are represented for each peak systole where it is observed that there is significant variation in the spatial parameters between the two models considered in the study. Comparison of local shear stress magnitude in different branches namely Common Carotid Artery (CCA), Internal Carotid Artery (ICA) and External Carotid Artery (ECA) show that the shear thinning property of blood influences the Wall Shear Stress (WSS) variation. This is observed in branches where there is reduction in diameter and where the diameter reduces due to plaque deposition and also in the region where there is flow recirculation like carotid sinus.