Measurement of erythrocyte orientation in flow by spin labeling II--phenomenological models for erythrocyte orientation rate.
We present two phenomenological models describing the flowing erythrocyte orientation rate. The first concerns the onset of a stable orientation in a very dilute erythrocyte suspension. It is based on a simple formula for erythrocyte elongation as a function of shear stress, and we assume that beyond a threshold of elongation, erythrocytes take on a stable orientation, while below this threshold, they have a flipping motion. We extend this model to high hematocrit values assuming that the effect of red cell collisions imposes a random moment to each erythrocyte, shifting it from its stable orientation. We obtain an approximate expression for erythrocyte orientation rate as a function of shear rate and then we compare these results to our experimental data in part III of this series.
D001696:Biomechanical Phenomena; D004912:Erythrocytes / Q000502:physiology*; D007700:Kinetics; D008433:Mathematics; D008954:Models, Biological; D012212:Rheology; D013113:Spin Labels
D013113:Spin Labels