Validation of numerical models for flow simulation and wave propagation along human aorta

Abstract

Numerical computations on 2d model of blood flow along human aorta based on incompressible axisymmetric Navier-Stokes equations for blood and momentum equations for incompressible viscoelastic arterial wall are compared to the blood flow oscillation curves measured in vivo by Doppler ultrasound in the larger systemic arteries of healthy volunteers. The analysis of the wave propagation and reflection along the geometrical 91-tube model of aorta as a tube with side branches is based on Lighthill’s theory of waves in arteries. It is shown due to individual geometry positive wave reflections at some aortic branches and aortic bifurcation may lead to increase of the pressure amplitudes, high pressure and wall shear stress oscillations that may lead to wall damage and development of aortic aneurism and stenoses of branched arteries. The numerical results obtained on the linearized 2d and nonlinear 1d models are compared to the in vivo pressure and flow measurements along the aorta and in its branches. A good qualitative correspondence is obtained. The model can be used for determination of the individual parameters for patient-specific cardiovascular models.