Comparative Analysis of Newtonian and Non-Newtonian Viscosity of Blood On Flow in an Intracranial Aneurysm

Abstract

A saccular intracranial aneurysm (IAs) is studied for the variations in the hemodynamic parameters and the flow visualization while modeling the blood as non-Newtonian in place of Newtonian. This study is a preliminary investigation for the experimental research of aneurysm-on-chip. Wall shear stress (WSS), responsible for the hemodynamic loading on the arterial blood vessel and the aneurysm, is studied. A gradual patient-specific waveform is used as the inlet boundary condition. Blood dynamics affect the IAs region’s flow behavior and hemodynamic parameters. Blood shows nonNewtonian behavior due to red Blood Cells aggregation and deformation. Several non-Newtonian models show different results for different geometries and boundary conditions. So, the need arises for selecting the proper non-Newtonain, which shows similar variation as the patient-specific case. An attempt is made to choose the model by comparing it with the viscometric data. Compared to the viscometric data, the Quemada viscosity model can be used for non-Newtonian modeling. Non-Newtonian flows have higher viscosity at low shear rates, making them less likely to generate recirculation zones near walls and eddies. Newtonian models slightly underpredict the WSS values than non-Newtonian models.