Eventos Anais de eventos
EPTT 2024
14th Spring School on Transition and Turbulence
On the effect of turbulence modeling on the hemodynamics of intracranial aneurysms
Submission Author:
Iago Lessa Oliveira , SP , Canada
Co-Authors:
Marcella Dallavanzi, José Luiz Gasche, Heitor Temporim Ribeiro, Iago Lessa Oliveira
Presenter: Iago Lessa Oliveira
doi://10.26678/ABCM.EPTT2024.EPT24-0027
Abstract
Intracranial aneurysms (IAs) are dilations in the cerebral arteries, which can cause great danger if they rupture, causing intracranial hemorrhage and possibly leading to the death of the patient — IAs have a high mortality rate of up to 50 %. Rupture, however, is difficult to predict and, currently, surgical procedures also present risks for the patient. Numerical simulations of the flow within IAs have been widely used to study them due to the connection between hemodynamics and the initiation, growth and rupture of aneurysms, being the wall shear stress and the oscillatory shear index on the artery wall inner surface the main causes of evolution of an aneurysm. When using numerical simulations to solve this problem, adequate flow models are important and one of the most used hypotheses is that the flow is laminar, due to its low values of the Reynolds number. However, some studies indicate that transition to turbulence may occur inside the aneurysm due to the transient nature of the flow. In this context, it is important to check which turbulence models could be used to more adequately predict the wall shear stress in cases where transition occurs, which is the goal of this work. We numerically simulated the flow, using OpenFOAM®, inside an aneurysm case available in the Aneurisk repository using Computational Fluid Dynamics assuming, first, laminar flow regime, and with the k-ω SST and kT-kL-ω models by assuming that transition occurred. The results for wall shear stress and the oscillatory shear index were analyzed, indicating that the assumption of turbulence inside the aneurysm is indeed small.
Keywords
Intracranial aneurysms, Turbulence, Computational fluid dynamics (CFD), Wall Shear Stress
