NUMERICAL SIMULATION OF FLUID DYNAMICS IN A CAROTID ARTERY BIFURCATION SUBJECTED TO PROGRESSIVE ATHEROSCLEROTIC OBSTRUCTION: A THREE-DIMENSIONAL ANALYSIS OF VELOCITY AND PRESSURE TRANSITIONS
Mostefa Belhocine1, Hichem Amrani2, Kamel Fedaoui2, Hammoudi Mazouz1,3, Abdelyamine Boukhobza2,5, Lahcene Mebarki4,5
1Department of mechanic, Faculty of technology, University Batna 2, Algeria,
2HNS-RE2SD, Batna, Algeria,
3LRP laboratory, University Batna 2, Algeria,
4Mechanics Research Center (CRM), Constantine, Algeria
5LSETER Laboratory, Technology Institute, Nour Bachir University Center, El-Bayadh, Algeria
Abstract: Carotid artery stenosis severely alters local hemodynamics, presenting a critical risk factor for ischemic stroke, yet simplified two-dimensional models fail to capture the complex, out-of-plane fluid dynamics induced by patient-specific plaque geometries. To address this, a three-dimensional 3D numerical fluid dynamics analysis was developed within COMSOL Multiphysics to quantitatively characterize the critical velocity and pressure transitions under progressive levels of lumen narrowing. Integrating the Navier-Stokes equations for an incompressible, pulsatile fluid domain, the simulation utilizes the non-Newtonian Carreau model to accurately map shear-dependent blood viscosity variations across the geometric obstructions. The numerical simulations reveal that progressive plaque growth triggers an exponential rise and severe spatial asymmetry in flow velocity directly at the stenotic throat, which then undergoes structural breakdown to generate massive, multi-axial recirculation zones and chaotic eddies upon entering the post-stenotic region. Concurrently, the Venturi effect induces a sharp, localized drop in static pressure within the narrowing to establish a steep translesional pressure gradient, while the kinetic energy of the disrupted downstream jet is permanently dissipated as heat due to intense viscous losses, severely inhibiting uniform pressure recovery. Ultimately, this 3D computational framework successfully captures the intrinsic coupling between high-velocity jetting and severe localized pressure drops, providing an objective engineering framework to assess the clinical severity of progressive carotid obstructions beyond standard geometric measurements.
Keywords: Atherosclerosis, Carotid Bifurcation, COMSOL Multiphysics, Particle Tracing, Hemodynamics.
VOLUME 10 ISSUE 07 2026: 75 – 86