The physics of arteriole blood flow II. Comparison with experiment

The results of paper I, General theory, are used to explain, using a continuum physics approximation, some of the experimentally observed phenomena which appear in the literature. The magnitude of the new dimensionless similarity parameter which arises from the mixture theory indicates that the internal frictional force acting on the plasma due to the presence of the erythrocytes (with an equal and opposite force acting on the erythrocytes due to the plasma) dominates the internal plasma viscous force. It is this feature that produces the observed slower flow rate of blood compared with water for a given pressure gradient. Quantitative predictions, which agree with experiment, of the cell-free layer, feed, dynamic and discharge haematocrits for cylindrical pipe flow are obtained. The observed decrease in apparent blood viscosity with decrease in cylinder diameter is also predicted. Finally an explanation is presented for the experimental observation of an off-centre peak in the tube radial viscosity profile.