The human lung is made up of 300 million alveoli, each about a quarter of a millimetre in diameter. On inspiration (breathing in) these alveoli fill up with air, and provide an interface to capillaries so that oxygen can diffuse into the blood stream.
The size and shape of the alveoli can change either as a result of ageing or due to the onset of disease. These changes alter the mechanics of the patient’s breathing.
Therefore, modelling alveolar mechanics is necessary to link microstructural changes to the patient’s breathing patterns. Alveolar models are best represented as ‘space-filling truncated polyhedra’, which look hexagonal in cross-section.