154
Dynamics
of
the
Vascular
System
Fig.
5.2.7:
Wall shear stress during the pulse cycle at the inner wall (internal divider wall)
Bi, Di and at the outer internal wall Bo,
Do.
Solid line: compliant model; dashed line:
rigid model. From Perktold and Rappitsch
(1995).
5.2.2
Fluid Mechanics Associated with Atherosclerosis and Stenosis
The susceptibility
of
vascular branches to atherosclerosis is believed due
in part to the unusual fluid dynamic environments that the vessel wall
experiences in the regions.
Fluid mechanical studies have shown that
atherosclerosis may occur at branching points where the geometry is
complex, a large Reynolds number and a lower than average wall shear
stress. In general, the complex flow pattern is associated with
a
spatially
nonuniform shear stress and wall curvature. The rate
of
change
of
shear
