INSPIRATORY PARTICLE DEPOSITION IN AIRWAY BIFURCATION MODELS

Particle deposition in a three-dimensional bifurcation model of the human lung was computed for simultaneous effects of inertial impaction and gravitational settling. In the present approach an anatomical bifurcation unit is characterized as a contiguous system of three straight tubes with two intermediate bends, with defined radius of curvature and an effective branching angle. Idealized flow profiles of uniform velocity in the straight segments and of rotational velocity in the bend portions were assumed, the latter being corrected for physiologically realistic flow conditions. Our theoretical results show excellent agreement with published experimental data. This model is then used to predict aerosol deposition in the symmetrical Model A of Weibel [Weibel, E. R. (1963) Morphometry of the Human Lung. Springer, Berlin] and to study the effect of airway variability and asymmetry on particle deposition in the human lung.