Particle Deposition in Replicate Casts of the Human Upper Tracheobronchial Tree Under Constant and Cyclic Inspiratory Flow. I. Experimental

The deposition of 3 μm and 8 μm monodisperse aerosols was examined in replicate casts of the human upper tracheobronchial tree under conditions of constant and cyclic “inspiratory” flow, having mean rates of 15, 30, and 60 L/min. Bronchial deposition efficiency was greater under cyclic than under constant flow at all exposure conditions, although a greater difference between the two flow regimes was found for the smaller particles. Values for average deposition surface density were also derived. The results are related to possible flow patterns and boundary layer conditions occurring in the casts.