Influence of Plasma Layer on Steady Blood Flow in Microvessels

Abstract

A semi-empirical new model for steady blood flow in microvessels is proposed. In the model, a peripheral layer devoid of blood cells (called the plasma layer) is taken into account and the central core of blood surrounded by the plasma layer is assumed to obey the Herschel-Bulkley equation. The velocity distribution and the pressure-flow relation have been derived for the model. To study the rheological condition of the blood flow in arterioles, the model is compared with the experimental data obtained by Einav et al., using the Laser Doppler anemometry. It is found that the experimental data for velocity profiles are explained fairly well by this model, if appropriate values are chosen for parameters. A careful investigation of these data reveals that the blood flow in microvessels can be regarded apparently as a Newtonian flow owing to the presence of the plasma layer.