Abstract
The study aims to simulate the steady flow characteristics in the human left internal carotid arterial (LICA) aneurysm under various Reynolds numbers by numerically solving incompressible Navier-Stokes equations. Solutions were generated by an unstructured gird system and a cell-center finite volume method that used second-order upwind and center flux-difference splitting for the convection and diffusion terms, respectively. SIMPLEC algorithm was adapted to treat the pressure-velocity coupling problem. The three-dimensional (3-D) complex geometry of the human left carotid arterial aneurysm was reconstructed from a series of 2-D magnetic resonance imaging (MRI) data. The maximal, minimal, and mean Reynolds examined were 850, 300, and 600, respectively. Results are illustrated in terms of the hemodynamic factors such as intra-aneurismal velocity vector-field, primary vortex structure, inflow rate into the aneurysm, wall shear stress, and pressure distributions. The results show that the inflow into the aneurysm is mainly through the aneurysmal orifice along the outer wall side of curved parent vessel. This finding is believed to provide an important site reference for implanting a stent for the treatment of LICA aneurysms. A further analysis indicates that the aneurysmal dome is the most risky site for rupture.