Gas transport in a model derived from Hansen-Ampaya anatomical data of the human lung.

The anatomical data of the human lung published by Hansen and Ampaya are used in a model of gas transport in the lung. The Bohr dead space is calculated from solutions of a transport equation where diffusivity is given by an empirical formula obtained by Sherer et al. A satisfactory agreement is found with experimental data obtained from simultaneous washouts of H2 and SF6 for respiratory frequencies ranging between 15 and 60 min-1 and tidal volumes between 200 and 1,800 ml. The results support the idea that molecular diffusion is the main but not the only physical phenomenom which intervenes in gas mixing during breathing.