Fig. 1
From: The role of heterogeneity in asthma: a structure-to-function perspective
(reproduced with permission from [54])
Schematic of the Horsfield lung model. Individual airways are modeled with a lumped six element model with an alveolar tissue element at the terminal units based on a given order (n) and a recursion index (Δ). The dog lung model depicted here is comprised of 47 airway orders with a defined length and diameter. Each airway consists of a resistive component (R), an inertial component (I), and as well as a term to account for shunting into gas compression in the tube (Cg) and into nonrigid airway walls (Zw). The viscoelastic alveolar tissue element is modeled with a tissue damping term (G) coupled to elastance (H) and an inertial tissue component (Iti) with a gas compression corresponding to the volume of the alveolus (Cg)