The Character of Expiratory Flow in the Lung

Abstract

The primary objective of this study is to predict the expiratory pressure-flow relationship in a human lung. Experiments and analysis of the flow in a single bifurcation provides a means to numerically synthesize the pressure-flow character for a complete lung, as well as providing insight to the fluid dynamic character of expiratory flow. A novel experimental technique was developed to measure the pressure drop across a single bifurcation within a multigeneration airway model. Energy considerations allowed the pressure drop to be separated into components owing to kinetic energy fluxes and viscous energy dissipation. Experiments were first conducted in an idealized symmetric, planar airway spanning the physiologically important Reynolds number range from 50 to 8000. Sensitivity of the results was determined for typical pulmonary conditions; Non-planar geometries L/D ratio variations Non-circular airway shape Asymmetric flow conditions Turbulent/Laminar flow regimes. The numerical simulations of the human lung generated excellent agreement with available physiological data. Different morphometric models were investigated, demonstrating the importance of the asymmetric geometry of the lung. Thesis Supervisor: Dr. Roger D. Kamm Title: Associate Professor of Mechanical Engineering

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Cite this paper

@inproceedings{Collins2015TheCO, title={The Character of Expiratory Flow in the Lung}, author={John Mulloy Collins}, year={2015} }