Abstract
This study looks into the intricate dynamics of blood flow within a blood vessel with both stenosis and dilatation. Unlike previous studies, blood is modeled as a Sisko non-Newtonian fluid, departing from the traditional Newtonian assumption, in order to accurately depict its non-Newtonian behavior. The Sisko model is a flexible tool for hemodynamic research since it is used for a broad variety of arterial circumstances, such as different dilation geometries and degrees of stenosis. To investigate the effects of changing the Sisko fluid properties on blood flow through the vessel, thorough parametric research is carried out by considering various model parameters using the finite element method (FEM). This study mainly focuses on the fluid flow behavior in the post-stenotic dilatation. The influence of stenosis severity, dilatation extent, and flow parameters on hemodynamic features is investigated. The fluid motion is explained by using the governing equations. The modeled governing equations are solved using the finite element method (FEM), which breaks down the artery into smaller computationally manageable elements using a normal mesh. A weak formulation has been derived by multiplying the governing PDEs by appropriate test functions and then integrating over the domain. Appropriate boundary conditions are defined, including no-slip at the artery wall, normal inward velocity, general inward heat flux, and outlet pressure. Numerical simulations are used to examine velocity patterns, shear stress distribution, and pressure drop throughout stenotic and dilated regions. Additionally, variations in temperature and heat transfer are also examined as potential causes of effects on blood flow. The Sisko model's governing equations are shown in cylindrical coordinates. It has been observed that when blood passes through stenosis, its velocity increases and its pressure lowers as a result of greater flow resistance. Also, a small temperature increase occurs from viscous heating in the stenotic area. Further study shows that the parametric variation in the model parameter also affects the hemodynamics of fluid flow. The results are shown graphically in order to better understand the hemodynamics of blood under various parameters. The results aid in the development of cutting-edge diagnostic and treatment approaches and offer insightful information about the pathophysiology of artery illnesses. This study would provide insight into the long-term effects of vascular disease by examining the effects of developing atherosclerosis on hemodynamic parameters and blood flow patterns in the presence of post-stenotic dilatation.