Airway reopening through catastrophic events in a hierarchical network

Baudoin, Michael; Song, Yu; Manneville, Paul; Baroud, Charles

Document type :

Compte-rendu et recension critique d'ouvrage

DOI :

10.1073/pnas.1211706110

Title :

Airway reopening through catastrophic events in a hierarchical network

Author(s) :

Baudoin, Michael [Auteur]

Institut d’Électronique, de Microélectronique et de Nanotechnologie - UMR 8520 [IEMN]
Laboratoire d'hydrodynamique [LadHyX]
Song, Yu [Auteur]
Laboratoire d'hydrodynamique [LadHyX]
Manneville, Paul [Auteur]
Laboratoire d'hydrodynamique [LadHyX]
Baroud, Charles [Auteur correspondant]
Laboratoire d'hydrodynamique [LadHyX]

Journal title :

Proceedings of the National Academy of Sciences of the United States of America

Pages :

859-864

Publisher :

National Academy of Sciences

Publication date :

2013

ISSN :

0027-8424

HAL domain(s) :

Sciences de l'ingénieur [physics]

English abstract : [en]

When you reach with your straw for the final drops of a milkshake, the liquid forms a train of plugs that flow slowly initially because of the high viscosity. They then suddenly rupture and are replaced with a rapid airflow ...
Show more >When you reach with your straw for the final drops of a milkshake, the liquid forms a train of plugs that flow slowly initially because of the high viscosity. They then suddenly rupture and are replaced with a rapid airflow with the characteristic slurping sound. Trains of liquid plugs also are observed in complex geometries, such as porous media during petroleum extraction, in microfluidic two-phase flows, or in flows in the pulmonary airway tree under pathological conditions. The dynamics of rupture events in these geometries play the dominant role in the spatial distribution of the flow and in determining how much of the medium remains occluded. Here we show that the flow of a train of plugs in a straight channel is always unstable to breaking through a cascade of ruptures. Collective effects considerably modify the rupture dynamics of plug trains: Interactions among nearest neighbors take place through the wetting films and slow down the cascade, whereas global interactions, through the total resistance to flow of the train, accelerate the dynamics after each plug rupture. In a branching tree of microchannels, similar cascades occur along paths that connect the input to a particular output. This divides the initial tree into several independent subnetworks, which then evolve independently of one another. The spatiotemporal distribution of the cascades is random, owing to strong sensitivity to the plug divisions at the bifurcations.Show less >

Language :

Anglais

Popular science :

Non

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