Simulation Study on Characteristics of the Vortex Structure in Human Mouth-throat Model in Cyclic Respiratory Pattern

Abstract

The research on vortex structure and vortex evolution in human upper respiratory tract can deepen understanding of the characteristics of the airflow in human upper respiratory tract and plays a very important role in analyzing the diffusion, transition and deposition patterns of aerosol in human upper respiratory tract. Large eddy simulation was used to simulate the vortex structure and vortex movement in human mouth-throat model in cyclic respiratory pattern, and the vortex structure and vortex evolution in mouth-throat model was discussed. The results show that jet formations in pharynx and laryngeal lead to two vorticity growth regions at cyclic inhalation flow, flat vortex appeared in the throat, a curved vortex like the trachea wall appeared in the anterior wall of trachea, and nearly symmetric reverse vortex pairs appeared in the trachea; a vortex like “3” appeared in the posterior wall of the throat, two curved vortexes like eyebrow appeared in the posterior wall of the pharynx.