Hemodynamics of Physiological Blood Flow through a Double Stenosed Artery

Abstract

A numerical analysis of physiological blood flow in a rigid artery has been performed to observe the variation in flow pattern and hemodynamic parameters under the influence of double stenoses. A finite volume method has been employed to solve the governing equations for the two dimensional, unsteady, laminar flow of an incompressible and Newtonian fluid. The dynamics of flow feature have been studied by wall pressure, streamline contour, wall shear stress and axial velocity distribution for all models. Besides, time average wall pressure and time average wall shear stress have been studied. The interspacing distance between two stenoses and the degree of stenosis severity have been varied. The pulsatile flow pattern used in the investigation has a Reynolds number range of 177 to 742. Flow parameters have been observed in five distinguished point in the velocity profile. It is observed that maximum pressure occurs at the point of maximum systolic velocity and minimum pressure occurs at minimum systolic velocity. Pressure increases with increasing stenosis severity and at low stenosis severity pressure increases with increasing inter spacing distance. Wall shear stress becomes maximum at maximum systolic velocity and does not change significantly with the change of interspacing distance at the region of first stenosis. But wall shear stress strongly influenced by the change of stenosis severity. It is found that axial velocity magnitude becomes maximum at maximum systolic velocity and maximum systolic de-acceleration. It is also found that axial velocity increases with increasing stenosis severity. Time average wall shear stress and time average wall pressure shows no significant change with increasing interspacing distance. But they tends to increase with increasing stenosis severity. Streamline contour shows that comparatively more vortex created at maximum systolic velocity and maximum systolic de-acceleration.