Unsteady laryngeal airflow simulations of the intra-glottal vortical structures.
The intra-glottal vortical structures developed in a static divergent glottis with continuous flow entering the glottis are characterized. Laryngeal airflow calculations are performed using the Large Eddy Simulation approach. It has been shown that intra-glottal vortices are formed on the divergent wall of the glottis, immediately downstream of the separation point. Even with non-pulsatile flow entering the glottis, the vortices are intermittently shed, producing unsteady flow at the glottal exit. The vortical structures are characterized by significant negative static pressure relative to the ambient pressure. These vortices increase in size and strength as they are convected downstream by the flow due to the entrained air from the supra-glottal region. The negative static pressures associated with the intra-glottal vortical structures suggest that the closing phase during phonation may be accelerated by such vortices. The intra-glottal negative pressures can affect both vocal fold vibration and voice production.
Mihaescu
Mihai
M
Department of Aerospace Engineering and Engineering Mechanics, University of Cincinnati, 310 Rhodes Hall, Cincinnati, Ohio 45221-0070, USA. mihai.mihaescu@uc.edu
Khosla
Sid M
SM
Murugappan
Shanmugam
S
Gutmark
Ephraim J
EJ
D000388:Air; D000399:Air Pressure; D003198:Computer Simulation; D005931:Glottis / Q000502:physiology*; D006801:Humans; D007700:Kinetics; D007830:Larynx / Q000502:physiology*; D008954:Models, Biological; D010699:Phonation / Q000502:physiology; D013997:Time Factors; D014827:Vocal Cords / Q000502:physiology