Publication detail
Time-resolved characteristics of oscillatory particle-laden air flow in a realistic human airway model
JEDELSKÝ, J. LÍZAL, F. JÍCHA, M.
English title
Time-resolved characteristics of oscillatory particle-laden air flow in a realistic human airway model
Type
journal article in Web of Science
Language
en
Original abstract
Human airways represent a complex flow system with a spatially and temporally variable character of air flow during respiration. In this paper, we experimentally studied the oscillatory flow of air with monodispersed micron-sized liquid particles in a transparent, anatomically realistic model of human upper airways and several bronchi generations using phase-Doppler anemometry (PDA). The PDA provided point-wise high-frequency measurements of axial velocities of individual aerosol particles in multiple positions of the airways (in the trachea and the upper bronchi) for three breathing regimes with a sinusoidal course. Typical time-resolved velocity plots at several positions within the model were documented and analysed using dimensionless criteria. Local mean air velocity and turbulence time-lines disclosed specific flow dynamic features in the multiple bifurcation system, namely the transit of vortical structures, oscillations induced by flow reversals, and inspiratory flow separations behind bifurcations. The results elucidated the laminar, transitional and turbulent flows during inspiratory and expiratory breathing phases. The character of the flow varies significantly with position in the airways, while the breathing regime has a generally low effect on the flow character. Inspection of the flow in the terminal branches indicated the need to add further branches for more realistic results there.
English abstract
Human airways represent a complex flow system with a spatially and temporally variable character of air flow during respiration. In this paper, we experimentally studied the oscillatory flow of air with monodispersed micron-sized liquid particles in a transparent, anatomically realistic model of human upper airways and several bronchi generations using phase-Doppler anemometry (PDA). The PDA provided point-wise high-frequency measurements of axial velocities of individual aerosol particles in multiple positions of the airways (in the trachea and the upper bronchi) for three breathing regimes with a sinusoidal course. Typical time-resolved velocity plots at several positions within the model were documented and analysed using dimensionless criteria. Local mean air velocity and turbulence time-lines disclosed specific flow dynamic features in the multiple bifurcation system, namely the transit of vortical structures, oscillations induced by flow reversals, and inspiratory flow separations behind bifurcations. The results elucidated the laminar, transitional and turbulent flows during inspiratory and expiratory breathing phases. The character of the flow varies significantly with position in the airways, while the breathing regime has a generally low effect on the flow character. Inspection of the flow in the terminal branches indicated the need to add further branches for more realistic results there.
Keywords in English
Aerosol transport; Airway model; Tracheobronchial tree; Upper airways; Human lungs; Oscillatory flow; Phase-Doppler anemometry; Gas-liquid two-phase flow
Released
16.03.2024
Publisher
ELSEVIER
Location
AMSTERDAM
ISSN
0997-7546
Volume
105
Number
May-June
Pages from–to
219–237
Pages count
19
BIBTEX
@article{BUT188693,
author="Jan {Jedelský} and František {Lízal} and Miroslav {Jícha},
title="Time-resolved characteristics of oscillatory particle-laden air flow in a realistic human airway model",
year="2024",
volume="105",
number="May-June",
month="March",
pages="219--237",
publisher="ELSEVIER",
address="AMSTERDAM",
issn="0997-7546"
}