Recent years have seen a rising interest in the use of computational fluid dynamics for investigating the hemodynamics in brain aneurysms. Hemodynamic parameters, such as wall shear stress or oscillatory shear index, are among the indicators used to detect higher risk of aneurysm rupture. This thesis describes the blood flow by generalized Navier-Stokes equations with the Navier slip boundary condition imposed on the impermeable rigid vessel wall, which is implemented by way of Nitsche's method. The influence of constitutive models and the Navier slip wall boundary conditions on the resulting blood flow and hemodynamic parameters is investigated. Five different non-Newtonian constitutive models are first compared on a 2D rectangular domain. The Carreau-Yasuda, modified Casson, and Quemada models are then employed to investigate the differences in one patient-specific aneurysm geometry obtained by CT scan. All non-Newtonian models are compared with the Newtonian model. Both steady and pulsatile simulations are performed to obtain the velocity field and hemodynamic quantities, such as wall shear stress, time-averaged wall shear stress, oscillatory shear index, and oscillatory velocity index. The results for this particular case showed that non-Newtonian models do not have a significant impact on the computed...
| Identifer | oai:union.ndltd.org:nusl.cz/oai:invenio.nusl.cz:448434 |
| Date | January 2021 |
| Creators | Trdlicová, Jana |
| Contributors | Hron, Jaroslav, Tůma, Karel |
| Source Sets | Czech ETDs |
| Language | English |
| Detected Language | English |
| Type | info:eu-repo/semantics/masterThesis |
| Rights | info:eu-repo/semantics/restrictedAccess |
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