Suspension model for blood flow through stenotic arteries with a cell-free plasma layer.

Abstract

The effects of the red cell concentration, the shape of the stenosis and a peripheral layer on blood flow characteristics due to the presence of a mild stenosis, are investigated. To account for the red cell concentration and the peripheral layer, blood is represented by a two-fluid model of particle-fluid suspension, and to estimate the effect of the stenosis shape, a suitable geometry has been considered such that the axial shape of the stenosis can be changed easily just by varying a parameter (referred to as the shape parameter). It is shown that the flow resistance increases with the cell concentration but decreases with increasing shape parameter. The existence of the peripheral layer causes significant reduction in the flow resistance. The wall shear stress distribution in the stenotic region and its magnitude at the maximum height of the stenosis (i.e., at stenosis throat) possess the variations similar to the resistance to flow with respect to any parameter except the shape parameter. The latter is independent of the shape whereas the former decreases in the converging zone as the shape parameter increases while it increases in the diverging zone in a similar situation. To discuss the physiological relevance, the analytical results are used to estimate the blood flow characteristics for different diseases using the experimental data and the present theoretical approach.