Newtonian and non-newtonian pulsatile blood flow in arteries with model aneurysms

Abstract

The cardiovascular diseases depend directly on the blood flow dynamics. The mathematical modeling and numerical simulations are expected to play an important role to predict the genesis of the atherosclerosis and the formation and rupture of the aneurysms. In the present work the numerical solutions for the oscillatory flow velocity due to the Newtonian and the non-Newtonian (Car-reau) model are constructed for a straight long tube and for a tube (artery) with a model aneurysm. The numerical solutions are obtained by the finite-difference method (FDM) for the straight tube and by the software ANSYS/FLUENT for both geometries. The numerical results obtained by the ANSYS/FLUENT for a straight long tube are validated by the analytical and numerical solutions using the FDM for the Newtonian and Carreau models for different Womersley numbers, correspondent to different tube radii. The obtained peak wall shear stresses from the oscillatory flow in the straight long tube are lower than those in the tube with the model aneurysm, which can be used as an indicator for further clinical examinations.