Biomedical Engineering Reference
In-Depth Information
Fig. 3
Axial flow velocity profiles at the symmetry plane during the pulse cicle
tp
, at selected
fractions of a period:
t/tp
D
0.05 (accelerated flow),
t/tp
D
0.1 (maximum flow rate) and
t/tp
D
0.14
(decelerated flow)
axial velocities and steep velocity gradients can be observed near the divider
wall. The shifting of the mass flow to the divider wall results from the branching
effect and from the curvature effect. A zone of special hemodynamic relevance
is the widened segment of the internal carotid, the carotid sinus. Time-dependent
stagnated and reversed flow occurs along the outer sinus wall (the wall opposite the
divider wall). During systolic acceleration
(t/tp
0.05), only forward directed flow
occurs in the sinus. At the end of flow acceleration (peak systole
t/tp
D
0.10) flow
stagnation can be observed at the outer sinus wall near the entrance to the internal
carotid. During systolic deceleration
(t/tp
D
D
0.14 where the inflow rate is the same as
