TITLE:
Effects of air sac compliances on flow in the parabronchi: Computational fluid dynamics using an anatomically simplified model of an avian respiratory system
AUTHORS:
Akira Urushikubo, Masanori Nakamura, Hiroyuki Hirahara
KEYWORDS:
Computational Fluid Dynamics; Avian Lung; Air Sacs; Compliance
JOURNAL NAME:
Journal of Biomedical Science and Engineering,
Vol.6 No.4,
April
29,
2013
ABSTRACT:
Air
flow in an avian lung was studied numerically to determine the effects of air
sac compliance on flow in the parabronchi. In this preliminary study, the geometry
of the avian respiratory system was simplified to capture the characteristics
of respiratory flow. The pressure fluctuation within air sacs caused by inflation
and deflation was expressed by a lumped parameter model. The results
demonstrate that the flow direction in the parabronchi varied, depending upon
the compliance of the air sacs. A unidirectional flow in the parabronchi was achieved for compliances where pressure
fluctuations in all air sacs were in phase. Air sac compliance significantly
affected the pressures in the anterior and posterior air sacs and thus
the pressure difference over the parabronchi that drove the flow in the
parabronchi. These results address the importance of air sac compliance in the
avian respiratory system and suggest that the compliance of air sacs would be
optimized to accomplish unidirectional flow in the parabronchi.