Multiphase CFD modeling of alumina nanoparticle drug delivery in bifurcated coronary arteries with stenosis, aneurysm, and bypass conditions

This study presents a novel computational framework for enhancing nanoparticle-assisted drug delivery in coronary artery disease (CAD), focusing on the complex hemodynamics in bifurcated arteries with stenosis, aneurysms and bypass grafting. The novelty lies in integrating alumina (Al₂O₃) nanoparticles into transient multiphase CFD simulations using ANSYS Fluent, incorporating advanced User-Defined Functions (UDFs) to replicate realistic pulsatile blood flow. Both Newtonian and non-Newtonian viscosity models are applied to more accurately represent blood rheology. Three-dimensional models of the left main coronary artery (LMCA), left anterior descending artery (LAD), and left circumflex artery (LCx) are developed using SOLIDWORKS. Twelve simulation cases are analyzed, including healthy arteries, diseased arteries (with stenosis and aneurysms), and arteries treated with bypass grafting, each tested with and without nanoparticles. Key hemodynamic parameters velocity, pressure, and wall shear stress (WSS) are compared across all cases. The results show that non-Newtonian modeling in the stenosed and aneurysmal artery (Case 7) yields the highest velocity and WSS, with a 7.96 % rise in velocity and a 220.98 % increase in WSS at systole compared to healthy and treated arteries. At diastole, velocity and WSS remain elevated by 2.64 % and 82.50 %, respectively. Nanoparticles raise arterial pressure by 12–20 %, but reduce aneurysmal pressure by 18 % post-bypass, suggesting improved hemodynamic stability. This integrated approach offers new insights into vascular biomechanics and supports the development of patient-specific, nanoparticle-based therapies. Contour visualizations highlight critical flow regions for drug targeting and surgical planning.