The transport of macromolecules across the arterial wall and their subsequent accumulation is an essential mechanism in the development of atherosclerosis, a slowly progressive, occlusive disease of large arteries. The analyzation of the various ways in which blood-borne substances are transported to and through the arterial wall is therefore important to a further understanding of this vascular disease. Pulsatile transport of albumin and oxygen is analyzed numerically in axisymmetric and three-dimensional domains using the finite element method. The flow dynamics is described applying the time-dependent Navier-Stokes equations, the mass transport is modelled by the convection diffusion equation. Experimental results have shown that the endothelium is a major barrier to solute wall flux and that its permeability strongly depends on wall shear stress. The boundary conditions for the transport equation take into account this endothelial resistance by means of a shear dependent permeability model based on experimental data. In order to enable a stable numerical calculation of the mass transport for high Peclet numbers a streamline upwind technique in combination with a subelement method is used. The applied numerical technique proves to be stable and efficient in both the two-dimensional and three-dimensional case.
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