Author/Authors :
Ashtiani، M. N. نويسنده Laboratory of Biomechanical Researches, Mechanical Engineering Department, Sahand University of Technology, Tabriz, Iran , , Tafazzoli-Shadpour، M. نويسنده Faculty of Biomedical Engineering, Amirkabir University of Technology, Tehran, Iran , , Najafi، H. نويسنده Department of Physics, University of Velayat, Iranshahr, Iran ,
Abstract :
Background: Several multiphase flow analyses have been developed to predict
the fate of particles used in inhalation drug delivery; however, the collapse of droplets
during their passage through respiratory tract has not been investigated.
Objective: To assess the probability of droplet collapse in the upper respiratory
tract.
Methods: A 3D model of mouth-to-second generation airway after the trachea
was developed with application of a computational fluid dynamics modeling. A new
parameter, the droplet collapsibility index (DCI), was defined to evaluate the probability
of droplet collapse during the release of droplets through the model.
Results: The results stated that droplets with diameter between 0.1 and 1 ?m are
at higher risk of collapse. Also, the most probable region of collapse was found to be
the glottal bend. The condition becomes progressively worse by increasing the rate
of breathing air flow. By increasing the inspiration flow rate from 10 to 30 L/min, the
droplet collapsibility rised from 0.75 to 2.25—exceeding the collapsibility threshold.
Conclusion: Results of the current study can be used in evaluation of collapsibility
of particles in design of inhalation drug delivery systems.
