Abstract
In order to determine the growth of inhaled aerosol particles in the human respiratory tract the relative humidity in a lung model has been calculated using a numerical method. The computations take into account different types of airflows, enhanced transport mechanisms and an optimized wall temperature profile in the upper airways. These parameters are varied to fit experimental temperature data. Under certain conditions the corresponding relative humidity shows a maximum near the first bifurcation, which exceeds the final humidity in the alveoli. This high humidity forces dry NaC1 particles with diameters less than 0.5 μm to grow to their maximum size in the first bronchi. Thereafter the droplets loose water and reach their final size in the terminal bronchioles.
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Ferron, G.A., Haider, B. & Kreyling, W.G. A method for the approximation of the relative humidity in the upper human airways. Bltn Mathcal Biology 47, 565–589 (1985). https://doi.org/10.1007/BF02460015
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DOI: https://doi.org/10.1007/BF02460015