Mass transfer and blood flow in a patient-specific three-dimensional Willis circle

Abstract

The paper carries on numerical mass transfer and fluid flow of a Non-Newtonian (Casson-like) blood in a complete patient specific Circle of Willis (CoW), for the first time in the literature. Pressures, fluid flow and mass transfer variables are presented. As far as the distribution of Wall Shear Stress (WSS) is concerned, the paper shows that regions with WSS greater than the fisiologic limit (equal to 150 dyne/cm2) tend to superimpose to vascular zones, typical of saccular cerebral aneurysms. Zones with high WSS coincide with those of high MGS, where, according to literature, the formation of cerebral aneurysms is more probable, as close to arterial branchings and cross section changes. As far as mass transfer of LDL and Glucose are concerned, greater concentrations are observed in zones more exposed to atherosclerosis risk. Zones with greater values of Sherwood number coincide with the regions with greater frequency of atherosclerotic plaques.