Abstr:AC7-01: Difference between revisions
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that are based on computational fluid dynamics for the prediction of aerosol deposition in | that are based on computational fluid dynamics for the prediction of aerosol deposition in | ||
the human airways has become very common nowadays. Despite their limitations, that | the human airways has become very common nowadays. Despite their limitations, that | ||
are mainly associated to their high computational cost, CFD models offer significant | are mainly associated to their high computational cost, CFD models offer significant advantages | ||
over ''in vitro'' / ''in vivo'' experiments. | |||
However, prior to their use CFD models | |||
need to be properly validated. This is the objective of the current application Challenge. | need to be properly validated. This is the objective of the current application Challenge. | ||
Specifically, ''in vitro'' deposition measurements using positron emission tomography (PET) | |||
have been conducted in a human—based model of the upper airway during steady—state | have been conducted in a human—based model of the upper airway during steady—state | ||
inhalation at flow rates of | inhalation at flow rates of 15, 30 and 60 L/min. The flow conditions at these flowrates | ||
are in the transitional t0 turbulent regime. CFD simulations were carried out in the | are in the transitional t0 turbulent regime. CFD simulations were carried out in the | ||
same geometry and under the same ventilation conditions. Two sets of simulations were | same geometry and under the same ventilation conditions. Two sets of simulations were | ||
Revision as of 08:45, 2 October 2019
Aerosol deposition in the human upper airways
Application Area 7: *****
Application Challenge AC7-01
Abstract
Knowledge of deposition Characteristics in the human airways is important when assessing the impact of inhaled aerosols, that can be either atmospheric pollutants or aerosols intended for therapeutic purposes. Not only the total deposition, but also local depositions within individual parts of the lung are of interest. The application of computer models that are based on computational fluid dynamics for the prediction of aerosol deposition in the human airways has become very common nowadays. Despite their limitations, that are mainly associated to their high computational cost, CFD models offer significant advantages over in vitro / in vivo experiments. However, prior to their use CFD models need to be properly validated. This is the objective of the current application Challenge. Specifically, in vitro deposition measurements using positron emission tomography (PET) have been conducted in a human—based model of the upper airway during steady—state inhalation at flow rates of 15, 30 and 60 L/min. The flow conditions at these flowrates are in the transitional t0 turbulent regime. CFD simulations were carried out in the same geometry and under the same ventilation conditions. Two sets of simulations were performed: Large Eddy Simulations using the dynamic version of the Smagorinsky—Lilly subgrid scale model and RANS simulations using the k—w—SST turbulence model. In both methods7 the Lagrangian approach has been adopted to track spherical particles in the airway geometry and determine regional deposition patterns.
The methods and results described in the present Application Challenge are mainly
adopted from Lizal et al. (2012) (experimental part) and Koullapis et al. (2018) (numerical
part).
Contributed by: P. Koullapis — ***
© copyright ERCOFTAC 2019