Fig 1.
Three levels of details of the human bronchial region.
a) Picture of a lung cast showing the human bronchial region. b) Schematic transverse view of an airway, with the different layers surrounding the lumen of the airway. c) The epithelial cilia penetrate in the ASL and generate the displacement of the mucus layer.
Fig 2.
Scheme of an airway in generation i and a bifurcation.
Several parameters related to the balance of the mucus in the airway are represented on this figure. The picture is not to scale.
Table 1.
Values of several parameters used in this work.
Fig 3.
Results obtained with the computational tool.
Left: calculated value of Ei/Si as a function of the generation index. Right: calculated average temperature of the air on a flow cross-section as a function of the distance from the top of the trachea, at the end of the inspiration (circles) and the expiration (squares). These results have been obtained with the computational tool, using tin = 2 s, f = 0.25 s−1, Qin = 250 ml s−1, Tin = 30°C and RHin = 0.80.
Fig 4.
Magnitude of the various mechanisms controlling the bronchial mucus balance.
The results were obtained with the data given in Table 1. Left figures: Tin = 30°C and RHin = 0.80, right figures: Tin = 34°C and RHin = 0.95. Top figures: δμ1 = 10 μm, vμ1 = 5 mm min−1, δμ16 = 2 μm and vμ16 = 0.5 mm min−1. Bottom figures: δμ1 = 30 μm, vμ1 = 5 mm min−1, δμ16 = 3 μm and vμ16 = 0.5 mm min−1. Squares-continuous lines: ΔMi, diamonds-dashed lines: Ei, circles-dotted lines: Bi.
Fig 5.
Schematic diagram of an airway, during inspiration.
Several notations used in the model are presented on this figure. The picture is not to scale.