Pulsatile flow of shear-dependent fluid in a stenosed artery

Abstract

This paper aims to investigate the blood flow in a bell-shaped constricted rigid tube, modeled as stenosed artery. The flow is assumed to be axi-symmetric, laminar and of oscillatory type. A mathematical model of shear-thinning fluid corresponding to the shear-dependent blood viscosity (mainly due to the behavior of the red blood cells in suspension of the flowing blood) is considered. The governing equations of motion are presented with the help of stream function-vorticity and are solved numerically by finite-difference technique. The shear-thinning fluid model for the flowing blood has significant contribution in the dynamics of oscillatory blood flow. The results reveal that the arterial wall shear stress reduced significantly and the peak value of the wall shear stress at the maximum area reduction is comparatively low for Newtonian fluid viscosity. The lengths of recirculating regions formed after the constriction are reduced for the shear-thinning blood viscosity model and also for its different material parameters

Non-Newtonian Rheology in Blood Circulation

“…The non-Newtonian effects are also influenced by the type of deformation, being shear or elongation [16]. The impact of the non-Newtonian effects can be amplified by a number of factors such as pathological blood rheology and flow in stenosed vessels and stents [30][31][32][33]. An interesting finding of one study [34] is that although flow resistance and wall shear stress increases as the size of stenosis increases for a given rheological model, the non-Newtonian nature of blood acts as a regulating factor to reduce the resistance and stress and hence contribute to the body protection.…”

Numerical Simulation of Mass Transfer in Pulsatile Flow of Blood Characterized by Carreau Model under Stenotic Condition

“…Several non-Newtonian models for viscosity of blood are available in literature. Unfortunately few research works have been carried out to study the hemodynamics in a stenosed artery by considering blood as a non-Newtonian fluid (Nakamura and Sawada 1990;Misra et al 1993;Pontrelli 2001;Mandal et al 2012;Nandakumar et al 2015 andMukhopadhyay et al 2018a). With the help of Carreau model, Ali et al (2015) analyzed the unsteady blood flow through a tapered catheterized vessel having an overlapping stenosis.…”

Mathematical Modelling of an Atherosclerotic Blood Flow Through Double Stenosed Region with Application of Treatment

“…This is one of the reasons for the lack of consensus among researchers on necessity of considering non-Newtonian properties of the blood. Some scientists believe that the non-Newtonian properties should be considered only for calculations of small vessels (less than 0.5 mm [7]) when the value speed and tangential stresses are small so for relatively large elements of the circulatory system simulations carried out with Newtonian or power-law fluid models [8].…”