Three-dimensional time-dependent incompressible Navier-Stokes equations are numerically solved in a body fitted coordinates system to study the pulsatile blood flow in a human aortic arch. A projection-type method is employed and to accelerate the numerical convergence of the flow field at each time step, two new pressure corrections are applied. First correction is based on the acceleration of the entry flow and the second one is designed to satisfy the continuity of mass fluxes in every cross section. A rescaled Newtonian model has been employed to predict the non-Newtonian blood behavior. Flow patterns in rescaled Newtonian fluid are studied in several section of the artery. The wall shear stresses, which are of much importance in the initiation of vascular diseases, are studied for both Newtonian and rescaled Newtonian fluid. The results indicated that inner regions close to the inlet of the aorta arch, with high wall shear stress values are vulnerable sites to the initiation and development of thrombus formation lesions which leads to atheroembolic stroke. On the other hand, regions with low values of WSS along the inner and outer walls are most susceptible to genesis of atherosclerosis disease. Present results indicate that the rescaled Newtonian model greatly influenced the axial velocity profiles and WSS distributions.

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