Simulation of particle deposition in human central airways

Piglione, Maria Chiara; Fontana, Daniela; Vanni, Marco

doi:10.1016/j.euromechflu.2011.08.003

Cited by 25 publications

(23 citation statements)

References 51 publications

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“…Numerical simulation is widely used by researchers to study the transport and deposition of particles in human airway [2][3][4]. Most of the studies are based on the assumption of dilute particle flow and the particle level phenomena are usually neglected.…”

Section: Introductionmentioning

confidence: 99%

Transport and deposition of cohesive pharmaceutical powders in human airway

Wang

Chu

2017

EPJ Web Conf.

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Abstract. Pharmaceutical powders used in inhalation therapy are in the size range of 1-5 microns and are usually cohesive. Understanding the cohesive behaviour of pharmaceutical powders during their transportation in human airway is significant in optimising aerosol drug delivery and targeting. In this study, the transport and deposition of cohesive pharmaceutical powders in a human airway model is simulated by a well-established numerical model which combines computational fluid dynamics (CFD) and discrete element method (DEM). The van der Waals force, as the dominant cohesive force, is simulated and its influence on particle transport and deposition behaviour is discussed. It is observed that even for dilute particle flow, the local particle concentration in the oral to trachea region can be high and particle aggregation happens due to the van der Waals force of attraction. It is concluded that the deposition mechanism for cohesive pharmaceutical powders, on one hand, is dominated by particle inertial impaction, as proven by previous studies; on the other hand, is significantly affected by particle aggregation induced by van der Waals force. To maximum respiratory drug delivery efficiency, efforts should be made to avoid pharmaceutical powder aggregation in human oral-to-trachea airway.

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Section: Introductionmentioning

confidence: 99%

Transport and deposition of cohesive pharmaceutical powders in human airway

Wang

Chu

2017

EPJ Web Conf.

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“…Therefore, the particles that remain airborne are easily expelled through the pressure outlet of the airways for rest and light activity (Kim and Iglesias, 1989;Nazridoust and Asgharian, 2008). However, the studies of Piglione et al (2012) and Feng et al (2016) found out that for inhalation during rest, a high concentration of fine particulates advanced to the alveolar region where they might cause harm (Piglione et al, 2012;Feng et al, 2016). Particle diameter P d1 = 0.075 µm, P d2 = 0.15 µm, P d3 = 0.3 µm, P d4 = 0.6 µm.…”

Section: Particle Deposition In Healthy Airwaysmentioning

confidence: 99%

“…Therefore, the maximum air flow velocity occurring at the inhalation time of 1.0 s (Fig. 2) is used to show the flow velocity variations for inhalation during rest, light activity, and moderate exercise (Piglione et al, 2012). The axial velocity contours and streamlines distribution for a healthy bifurcation under the three inhalation statuses are shown in Figs.…”

Section: Air Flows In Healthy Airwaysmentioning

confidence: 99%

“…Peak flows are usually applied in numerical simulations for airflow in the human airways to represent the transient flow (Piglione et al, 2012). Therefore, the maximum air flow velocity occurring at the inhalation time of 1.0 s (Fig.…”

Section: Air Flows In Healthy Airwaysmentioning

confidence: 99%

“…Different levels of activity and their corresponding parameters for the breathing conditions are summarized in Table 2. The average inlet velocity was described at the entrance of the parent branch as shown (Piglione et al, 2012):…”

Section: Boundary Conditions Parabolic Inlet Velocitymentioning

confidence: 99%

See 2 more Smart Citations

Flow Dynamics and PM2.5 Deposition in Healthy and Asthmatic Airways at Different Inhalation Statuses

Chen

Lee

Mutuku

et al. 2018

Aerosol Air Qual. Res.

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Public health reports indicate that high PM 2.5 concentration can impair the respiratory health of the residents, especially for those affected by asthma. Therefore, there is a need to determine the deposition mechanism and efficiencies for PM 2.5 in asthmatic human airways. In this study, gas flow dynamics and deposition fractions (DFs) of PM 2.5 in generations 10-11 of Weibel's lung model were investigated where the two-phase gas-solid flow behaviors in healthy and asthmatic airways were considered. The gas phase was modeled as a transient laminar and incompressible flow while the discrete phase model (DPM) was applied for the particle phase. Three different air flow rates under rest, light activity, and moderate exercise were considered. For the healthy airways, higher total mass DFs were observed during a moderate exercise as compared to rest and light activity conditions. Deposition fractions were higher in asthmatic airways compared to those of healthy ones, stemming from tapering in the airways as well as complex secondary flow fields, namely, Dean vortices, in the folds. Deposition was mainly due to inertial forces of particles, but a small amount of PM 2.5 was deposited near the entrance of asthmatic tube, as a result of the secondary flow. The numerical results revealed that the Dean vortices was an important factor for particle deposition. With increased DF, asthmatic people have a higher total respiratory dose of PM 2.5 for a given exposure compared to healthy individuals. Thus contributing to their increased susceptibility to adverse health effects caused by PM 2.5 .

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