Flow and Mass Transfer in Capillary Blood Oxygenator Equipment

The flow of blood and the transport of blood gases in membrane capillary tubes is investigated analytically in order to provide a basis for the rational design of artificial gas transfer devices. Models for the transport phenomena in both intermediate-sized and erythrocyte-sized tubes are formulated. For intermediate-sized tubes, solutions for a number of cases, including well-mixed blood, homogeneous unmixed blood, and nonhomogeneous blood having a plasma layer adjacent to the wall, are presented. The axial lengths required for blood oxygenation are given as functions of the physical parameters. For erythrocyte-sized tubes, the plasma flow patterns in the 'bolus' region and 'lubrication layer' are computed, and the influence of these regions on gas transfer is described. (Author)