AAAR 37th Annual Conference October 14 - October 18, 2019 Oregon Convention Center Portland, Oregon, USA
Abstract View
Glottis Opening Effects on Inhaled Particle Deposition in Human Airways
TED SPERRY, Yu Feng, Oklahoma State University
Abstract Number: 692 Working Group: Health-Related Aerosols
Abstract The objective of this study is to determine the influence of glottis opening on the pulmonary airflow and inhaled particle deposition patterns in a subject-specific human respiratory system. The glottis, or opening between the vocal cords within the larynx, has the narrowest passage in the upper respiratory system which may significantly influence transport and deposition of inhaled particles. Humans are exposed to aerosols from manufacturing, mining, construction, and pollution which produce airborne particles that may be inflammatory, carcinogenic, or carry infectious diseases into the subject airways. Using an experimentally validated computational fluid-particle dynamics (CFPD) model, this study focuses on the variability between three cases of identical bronchial trees with glottis opening areas of 83, 126, and 254 mm2 to explore the variations in airborne particle exposure risk. This study uses the Shear Stress Transport (SST) model to simulate the laminar-to-turbulent transitional airflow patterns with steady-state inhalation condition, then uses the Euler-Lagrange method to track particles. Specifically, these models reflect an inhalation rate of 30 L/min and introduce 100,000 particles with diameters of 0.5 µm for the first case and 2 µm for the second case. To isolate the effects of the glottic opening, the complex geometry of the mouth front was replaced by an idealized 20-mm circular inlet, which is identical for all cases. Numerical results indicate that glottis opening has a significant effect on local and regional particle deposition patterns, with the smaller glottis openings causing significant local deposition of inhaled particles when compared to that of the larger openings. Simulation results also suggest that future CFPD modeling efforts should realistically represent the glottis openings and dynamic motions to enable more accurate predictions of the flow patterns created by this structure and the resulting effects on particle deposition.