Coupled problems in computational modeling of the respiratory system

Lungs atre rather complex systems where both multiphysics and multiscale aspects are obvious and decisive. In this talk we will address some couples problems in the computational modeling of the respiratory system on quite different scales. Thereby we will focus on two regions - the lower airways, i.e. the upper bronchial tree, and the pulmonary alveoli. In the first generations of the bronchial tree, both fluid and fluid-structure interaction simulations are carried out for normal breathing and mechanical ventilation of the healthy and diseased lung. In addition differences between simulations with CT-scan based geometries and those from artificial geometries are studied. In case of pulmonary alveoli, the effect of interfacial phenomena on the overall mechanical behavior is analyzed. Therefore, an artificial 3D geometry of an alveolar ensemble based on a labyrinthine algorithm is generated. For modeling alveolar tissue, a hyperelastic polyconvex material model is employed.

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