Distributions of the water loss rate of subject A in the 1D CT-based central airways at: (a) 6 L/min, (b) 15 L/min and (c) 30 L/min. (b), (d) and (e) compare the distributions of the water loss rate of subject A predicted by the (b) the 1D model, (d) the CT-based model and (e) the 6-path model, respectively. (f) Distribution of water rate in the upper airway of subject A at 15 L/min. (i), (ii) and (iii) mark the locations of high water loss rate.