Abstract: Objective To apply computational fluid dynamics simulations of respiratory airflow in clinical examination, and individually measure the airflow motion parameters. Methods Ten healthy noses with normal nasal structure and function were axially scanned by spiral CT, simultaneously all volunteers were examined by GM Rhinomanometer NR6 and GM Acoustic Rhinometry A1. The continuous fault images of upper respiratory tract were imported into Mimics software for image segmentation and 3-dimensional models were obtained. Then model data were input to Ansys software to generate finite element mesh for transient computing and analysis. Rationality validation of workflow digital simulation was made from three aspects: 1 using acoustic rhinometry results to test the simulation of model; 2 setting transient boundary condition used airflow velocity value from Rhinomanometer results; 3 using air pressure value obtained from numerical simulation to calculate the nasal resistance value, then compared with the data from Rhinomanometer. Results The comparison indicates that the model and the numerical simulation were consistent. From the result we can observe the airflow distribution quantitatively in the nasal cavity in the period of respiration. Conclusion The model could truly reflect the actual anatomic structure and morphology of the nasal cavity, numerical simulation results were reliable. The airflow in the upper respiratory tract can be individualy measured.

Key words: upper respiratory tract, computational fluid dynamics, individualized measurement