Effect of non-Newtonian fluid rheology on an arterial bypass graft: A numerical investigation guided by constructal design

In post-operative scenarios of arterial graft surgeries to bypass coronary artery stenosis, fluid dynamics plays a crucial role. Problems such as intimal hyperplasia have been related and wall shear stresses near the junction. This study focused on question use Newtonian non-Newtonian models represent blood in this type problem order capture important flow features, well an analysis performance geometry from view Constructive Theory. The objective was investigate effects rheology steady-state system consisting idealized version partially obstructed graft. Constructal Design Method employed with two degrees freedom: ratio between diameters junction angle at inlet. solved numerically using Finite Volume modeled employing Carreau equation for viscosity. Computational Fluid Dynamics model associated Sparse Grid method generated eighteen response surfaces, each representing severe stenosis degree 75% specific combinations rheological parameters, dimensionless viscosity ratio, number index distinct Reynolds numbers 150 250. There considerable dependence pressure drop parameters. For studied, case presented lowest value drop, suggesting that choice applying may underestimate by about 12.4% (Re =150) 7.8% = 250). Even so, results demonstrated parameters did not influence either shape surfaces or optimum geometry, which consisted diameter 1 30°. However, had greatest impact recirculation zones stress. Rheological also affected downstream where is more prevalent. most similar stresses, except high ratio. Design, best independent model. played role dynamics, allowing prediction were captured