Numerical Simulation Study on Airflow Structural Characteristics in Real Human Airways Model

The transient airflow movement has tremendous effects on aerosol deposition in human airways. The understanding of the characteristics of the transient airflow movement in human airways plays a very important role in analyzing the aerosol deposition patterns. Computational fluid dynamics(CFD)was used to simulate the transient airflow movement in generations G1-G3 of real human airways model under light activity conditions, the transient airflow patterns in the middle plane and cross sections of the airways were discussed. The results showed that in the subglottic of jet of air in the trachea front wall is formed in the air, the air at around 9.96 m/s, in trachea rear form flow separation phenomenon, along with the increase of the distance with the subglottic, tracheal inside and outside wall airflow velocity difference gradually decreased, but before the trachea wall flow speed or to be higher than the back wall of the air speed; expiratory flow into the bronchial, endobronchial forming centre air in the air distribution of higher status, level 2 level 3 endobronchial air speed the most about 2.71 m/s,. In the bronchial bifurcate place, airflow happen intersection phenomenon, intersection cause at the center of the low speed area formed bifurcation, and join the level of airflow bronchial produce temporary two air at high speed.