Computational analysis of rest and exercise flow conditions in stenosed arteries using an in-house artificial compressibility solver

Abstract

This study investigates pulsatile incompressible flow through a stenosed artery-like geometry using a high-accuracy in-house numerical solver based on the artificial compressibility method. The artery is modeled as an axis-symmetric, rigid-walled conduit 45% area reduction due to stenosis. The flow is assumed incompressible, laminar, pulsatile and Newtonian. Centerline axial velocity profiles and wall shear stress (WSS) are computed at three axial locations and evaluated at selected phases of the cardiac cycle, with validation against available experimental and numerical data. The results demonstrate that the peak velocity scales directly with the flow rate. Simulations are performed using two physiological inlet velocity waveforms representing rest and exercise conditions. Under exercise conditions, the predicted WSS is approximately twice that observed during rest. Additionally, stenoses of varying severities and geometrical shapes (trapezoidal and bell-shaped) are constructed and compared. For both geometries, increasing stenosis severity leads to higher WSS, stronger near-wall flow reversal, and increased peak velocity at the stenosis throat. For the same degree of stenosis, trapezoidal geometries induce higher WSS than bell-shaped geometries. These findings highlight the combined importance of stenosis severity and geometric morphology in the hemodynamic assessment of cardiovascular diseases.