Numerical study of the effects of bifurcation angle on hemodynamics during pulsatile flow in a carotid artery bifurcation

To investigate the effects of the hemodynamics of arterial shape, mainly the bifurcation angle and sinus shape of the carotid artery, a computational model of the carotid artery has been constructed. In this research, we evaluate the distribution of velocity, pressure, and wall shear stress (WSS), time average wall shear stress (TAWSS) and oscillatory shear index (OSI). Three different carotid artery models with varying bifurcation angles with 33. with normal sinus shape, 45. with elliptical sinus shape and 63.3. with cylindrical sinus shapes have been subjected to computational fluid dynamics simulations. The research focuses on flow and stress characteristics in the carotid sinus. This study employs the fundamental equation of fluid mechanics, known as the Navier-Stokes equations, as the governing equation to assess hemodynamic parameters and determine blood flow characteristics. The simulation used the pressure correction finite volume method. For the non-Newtonian behaviour of blood, the Carreau model is used based on the measured dynamic viscosity. For pulsatile flow, a representative standard carotid artery bifurcation pulse wave is applied at the inlet of the common carotid artery model. The results show that the wider angle model exhibits a low WSS while the narrow angle model demonstrates a high WSS, indicating a high-risk area for atherosclerosis plaque, and regions with low and oscillatory shear stress in the carotid artery can lead to endothelial dysfunction.