NUMERICAL INVESTIGATION ON SHEAR-INDUCED MIGRATION OF ERYTHROCYTES IN IRREGULARLY CURVED CORONARY STENOSED ARTERIES

Abstract

Endothelial cells in large arteries receive less oxygen from migrating erythrocytes (Red Blood Cells) due to stenosis, which alters flow patterns. This investigation has been carried out to study how stenosis severity affects red blood cell (RBC) concentration distribution, shear-induced diffusion (SID), and wall shear stress (WSS) in irregular curved artery geometries with varying degrees of stenosis (DOS) 30%, 50%, 70%, and 90%. Most of the researchers’ studies focused on idealized straight geometries, whereas this work utilizes multiphase mixture theory simulations to mimic an accurate coronary arteries model of irregular curved geometries. A non-Newtonian viscosity model by Krieger and Phillips’s shear-induced diffusive flux model (DFM) is integrated to represent hemodynamics better. The multiphase transient non-Newtonian three-dimensional (3D) computational fluid dynamics (CFD) models have been used for variation DOS. A pulsatile blood flow condition is incorporated to study flow conditions in the curved coronary arteries. The results show that SID increases WSS by 82.98% between 70–90% of DOS, which indicates stenosis severity plays a significant role. At 90% stenosis, throat average velocity increased by 50 times compared to 30% stenosis, concentrating RBCs at the center and lowering blood viscosity and WSS at the wall. Clinically relevant findings suggest that sites with low WSS and reduced RBC concentration, as observed in this study, are closely linked to atherosclerosis development. These insights highlight the importance of SID and RBC distribution in understanding arterial stenosis and its results in cardiovascular disorders. © 2025 World Scientific Publishing Company.