K. Perktold et al., FLOW AND STRESS CHARACTERISTICS IN RIGID WALLED AND COMPLIANT CAROTID-ARTERY BIFURCATION MODELS, Medical & biological engineering & computing, 32(1), 1994, pp. 19-26
Computer simulation of pulsatile non-Newtonian blood flow has been car
ried out in different human carotid artery bifurcation models. In the
first part of the investigation, two rigid walled models are analysed,
differing in the bifurcation angle (wide angle and acute angle bifurc
ation) and in the shape of both the sinus (narrow and larger sinus wid
th) and the bifurcation region (small and larger rounding of the flow
divider), in order to contribute to the study of the geometric factor
in atherosclerosis. The results show a significant difference in the w
all shear stress and in the flow separation. Flow recirculation in the
sinus is much more pronounced in the acute angle carotid. an importan
t factor in flow separation is the sinus width. In the second part of
the study, flow velocity and wall shear stress distribution have been
analysed in a compliant carotid artery bifurcation model. In the mathe
matical model, the non-Newtonian flow field and the idealised elastic
wall displacement are coupled and calculated iteratively at each time
step. Maximum displacement of approximately 6% of the diastolic vessel
diameter occurs at the side wall of the bifurcation region. The inves
tigation demonstrates that the wall distensibility alters the flow fle
d and the wall shear stress during the systolic phase. Comparison with
corresponding rigid wall results shows that flow separation and wall
shear stress are reduced in the distensible wall model.