Investigation of Wall Shear Stress Related Factors in Realistic Carotid Bifurcation Geometries and Di erent Flow Conditions


Department of Mechanical Engineering,Sharif University of Technology


Cardiovascular diseases are one of the major causes of death in the world; atherosclerosis
being one aspect. Carotid bifurcation is one of the sites that are vulnerable to this disease. Wall Shear
Stress (WSS) is known to be responsible for the process of atherogenesis. In this study, we have simulated
the blood
ow for Newtonian and non-Newtonian, steady and unsteady,
ow conditions in three idealistic
and ve realistic geometries. A risk factor has been presented based on the results of wall shear stress and,
then, a relation was found between geometrical features and the wall shear stress risk factor. Our main
conclusions are: 1) The non-Newtonian behavior of blood elevates the value of wall shear stress, however,
the wall shear stress pattern is similar, 2) The bifurcation angle is not the main cause of atherosclerosis
and cannot be considered a predictor for atherosclerosis disease, and 3) The ratio of sinus diameter to the
internal carotid artery diameter is more important than other geometrical factors, and the WSS pattern
is in
uenced by this factor.