Capillary-elastic instabilities with applications to airway closure.The lung is comprised of a network of bifurcating airway tubes which are coated with a thin viscous film. Often times, especially in the case of disease, the liquid film can form a mensicus which fills the whole tube, thus obstructing airflow. The formation of the liquid mensicus is due to capillary driven instabilities which can arise in the lining, causing the lining to close up. In addition, airflow can also be obstructed if the airway tube collapses in on itself. This occurs when the elastic forces of the tube are not large enough to sustain the negative fluid pressures inside the tube, and the tube collapses. More recently, we have been looking at means of preventing closure, for example, the effects of an oscillatory shear stress on the air-fluid interface.
Movies of closure simulations.
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