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Flow development in a model airway bronchus

Published online by Cambridge University Press:  26 April 2006

B. Snyder  and
D. E. Olson
B. Snyder
Affiliation:
Department of Mechanical Engineering, University of Nevada - Reno, Reno, NV 89557, USA
D. E. Olson
Affiliation:
Department of Mechanical Engineering, Wichita State University, Wichita, KS 67208, USA
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Abstract

Three-dimensional laminar flow profiles were measured at each of three axial stations downstream from the inlet of a slowly tapering tube of constant flow cross-section. It was found that strong inlet wall shear induces significant secondary swirl, whose downstream growth is initially consistent with an inviscid model of vorticity transfer. This secondary flow may act to retard the onset of local flow separation by convecting axial momentum into the boundary layer adjacent to the diverging wall of the tube. These observations could account for the similar geometric shape of major bronchial airways: the suppression of flow separation in pulmonary bifurcations would promote moire effective airway ventilation in the human lung.

Type
Research Article
Information
Journal of Fluid Mechanics , Volume 207 , October 1989 , pp. 379 - 392
Copyright
© 1989 Cambridge University Press

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