Numerical Prediction of Flow Recirculation Length Zone in an Artery with Double Stenosis at Low and High Reynolds Numbers

This work presents simulation of arterial stenosis utilizing ANSYS (Fluent) Computational Fluid Dynamics (CFD) software package for better understanding of blood flow dynamics and to estimate the risk of complication. The aim of the paper is to investigate and study the effects of low and high Reynold’s number on recirculation zone length in arteries with varying levels of double stenosis. Blood flow was numerically simulated to predict the recirculation zone length and wall shear stress. An artery with double stenosis was studied and for the purpose of this investigation, stenosis levels of 15/15%, 75/75%, 15/75%, 75/15%, 15/60%, 20/60%, 45/60% 60/60%, and 75/60% in terms of proximal and distal stenosis are studied over the Reynolds number ranging from 150 to 3000. Blood was a Newtonian fluid flowing as a steady, three-dimensional, incompressible fluid. The velocity flow streamlines, and wall shear stress contours are presented. Results revealed that when varying both distal and proximal stenosis, as Reynolds number increases, recirculation zone length decreases in lower levels of stenosis between 15/60% and 45/60% while it remains relatively constant for higher levels of stenosis 60/60% and 75/60%. It was also revealed that when varying both distal and proximal stenosis, as Reynolds number increases, maximum wall shear stress increases gradually at lower levels of stenosis with almost equal values. At higher levels of stenosis, there was rapid increase in maximum wall shear stress as Reynolds number increases.