DOI: 10.1615/TSFP8
MULTI-PHASE BLOOD FLOW MODELLING IN AN INTRACRANIAL ANEURYSM CONSIDERING POSSIBLE TRANSITION TO TURBULENCE
要約
Intracranial aneurysms are abnormal dilatations of the
cerebral arteries that are, in case of a rupture, highly lifethreatening. Numerical investigations carried out to support clinical physicians are commonly assuming laminar flow conditions. However, especially in diseased arteries transition to turbulence has been observed.
To identify a possible transition, the effect of geometry
as well as of blood cells were investigated in the present
work. Therefore, hemodynamic simulations were carried
out under realistic flow conditions in an idealized basilar tip aneurysm. In addition, the impact of blood cells is examined using DNS with a pseudo-spectral code, adding Lagrangian spherical particles (using a point force approach) mimicking the suspension.
The statistical analyses revealed that even under normal
flow conditions fluctuations are observed during the
cardiac cycle. These appear at relatively high frequencies,
around 100 Hz. Additionally, the particulate phase significantly influenced the flow stability.
Hence, the results indicate that transitional effects
might indeed play a role to understand hemodynamics and
rupture of intracranial aneurysms, and should be accordingly taken into account.