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arXiv · 2406.09708

Modeling the effect of vorticity on inhaled transport in the upper airway

Saikat Basu·Leonardo P Chamorro·Mohammad Yeasin·Mark A Stremler
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Abstract

Localized vortices can have significant influence on transport of inhaled particles through the upper respiratory tract. These vortices have complex three-dimensional structure with details dependent on the anatomical geometry. Using a highly simplified model, we demonstrate that changes in transport characteristics with geometric distortion can be estimated by accounting merely for the net strength and location of the vorticity in a two-dimensional projection. Test cases consider 30 L/min inhaled airflow containing suspended spherical water droplets from 1 micrometer to 30 micrometers in diameter through (1) a healthy upper respiratory tract and (2) a distorted variation mimicking a glottic tumor. The reduced-order model approximates the system by a two-dimensional potential flow with embedded point vortices having features derived from Large Eddy Simulations of inhaled airflow through anatomically realistic, tomography-based, three-dimensional tracts. The effects of vorticity and particle size on changes in particle transport are shown to be consistent between the reduced-order model and the full-scale simulations.

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Saikat Basu, Leonardo P Chamorro, Mohammad Yeasin, Mark A Stremler. 2024-06-14. Modeling the effect of vorticity on inhaled transport in the upper airway. https://arxiv.org/abs/2406.09708

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