Coupling Multidimensional Compliant Models For Carotid Artery Blood Flow.

Abstract

A Finite Element implementation of a model of the blood flow through the carotid artery considering fluid wall interactions is presented. The Navier-Stokes equations are used as the governing equations for the blood flow while an elastic compliant model is implemented for the arterial wall. Also, the A.L.E. formulation is considered within the blood regions taking into account the domain deformations produced by the wall displacements. The former three-dimensional model is coupled with a one-dimensional one for the entire arterial tree in order to appropriately set inflow and outflow boundary conditions for 3D zones. The reduced 1D model solves the momentum and continuity equations in compliant tubes so as to reproduce the propagation of the pressure pulse in the arterial network. At the proximal entrance a volumetric flow rate is imposed as the inlet boundary condition to model the systolic work of the heart. The peripheral arterioles beds are simulated with the well known lumped windkessel model. The 3D Navier-Stokes problem is discretized with P1 Bubble-P1 tetrahedral elements using a standard geometry of the Carotid bifurcation. The obtained results adequately reproduce the general flow patterns reported in the literature. It is worthwhile to note that this kind of models may provide useful information for early detection, prevention and diagnosis of related arterial diseases