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Physiology of the respiratory system and mechanical models
The Mount model (Fig. 1.7) originally proposed by Mount [Mount, 1955] was resumed by
Bates [Bates et al, 1989]. It describes a homogeneous lung without any gas redistribution. In
this model, stress relaxation originates from lung tissue and/or surfactant viscoelastic
properties. The Mount model is composed of a Kelvin body (E 1 , R 1 ) associated in parallel
with a Maxwell body (E 2 , R 2 ). The total pressure is the sum of the pressures induced by the
Kelvin and the Maxwell bodies. The deformation of the Maxwell body is the sum of the
deformations of its elastic and resistive elements. Each of the two elements of the Kelvin
body is submitted to the same deformation as the Maxwell body.
c
Figure 1.7 Mount's model for homogeneous lung with tissue and/or surfactant component. (a) Anatomic
representation. (b) Rhelogic representation by a Kelvin body (E 1 , R 1 ) associated in parallel with a Maxwell body
(E 2 , R 2 ). (c) Electrical analog model.
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