Micro-particles Transport and Deposition in Realistic Geometry of Human upper Airways

The realistic geometry of human upper airways from the mouth to the end of the trachea was reconstructed by implementing the CT-Scan images of a male subject. A computational simulation wasdeveloped for analyzing the airflow in the airways. To capture the anisotropy of the inhaled airflow inthe upper airways, the Reynolds stress transport turbulence model was used in these simulations. The inhalation rates of 15, 30 and 60 l/min which represented the resting, normal and active conditions of human, respectively were underlined. The transport and deposition of micro particles in the realisticmodel of human upper airways were studied. The transport of micro particles was analyzed using the Lagrangian particle trajectory approach. Since the mass fraction of inhaled particles was very small, one-way coupling assumption was used. That is, the airflow carries the particles, but particles do notaffect the airflow condition. The predicted deposition fractions of the particles of different sizes in theupper airways were compared with the available experimental data to find good agreements. Comparison of the results of the deposition fraction obtained from the realistic model with the earliersimulations of the idealized geometry of the airways showed certain differences especially in regional depositions. Therefore, it was concluded that the realistic geometry must be used for more accurate evaluation of micro particle deposition rates especially for local and regional depositions

کلیدواژه ها:

Realistic Model ، Upper Oral Airways ، Micro Particles ، CFD ،