Effect of Aortic Arch Geometry on Pulsatile Blood Flow: Flow Pattern and Wall Shear Stress

The aorta, with complex geometry is one of the most vulnerable arteries for creation and development of cardiovascular diseases, especially atherosclerosis. Because of the association of disease with region of altered fluid mechanics, the role of blood flow in the localization of atherosclerosis has been extensively studied recently. The diameter of aorta, its branches, and the geometry of branches are parameters which affect the blood flow significantly. However, much less attention has been focused on the effect of these parameters and their association with diseased regions. In the present study, three different geometries of human aorta with three branches are constructed and blood flow inside the arteries is simulated. Flow across longitudinal crosssections of all three geometries is analyzed. The disturbed velocity profiles are observed near branchiocephalic, left common artery and left subclavian artery. On the other hand, the wall shear stress profiles at the roots of branches show significant differences with geometry variation of aorta and branches. The blood flow is considered as homogeneous, incompressible, and Newtonian fluid flow.

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