Intraglottal geometry and velocity measurements in canine larynges.
Previous flow velocity measurements during phonation in canine larynges were done above the glottal exit. These studies found that vortical structures are present in the flow above the glottis at different phases of the glottal cycle. Some vortices were observed to leave the glottis during the closing phase and assumptions were proposed regarding their formation mechanism. In the current study, intraglottal velocity measurements are performed using PIV, and the intraglottal flow characteristics are determined. Results from five canine larynges show that at low subglottal pressure the glottis assumes a minimal divergence angle during closing and the flow separates at the glottal exit. Vortical structures are observed above the glottis but not inside. As the subglottal pressure is increased, the divergence angle between the folds during closing increases and the location of the flow separation moves upstream into the glottis. Entrainment flow enters the glottis to fill the void that is formed between the glottal jet and the fold. Vortical structures develop near the superior edge at medium and high subglottal pressures from the flow separation. The magnitude of their swirling strength changes as a function of the wall dynamics.
Department of Otolaryngology-Head and Neck Surgery, University of Cincinnati, 231 Albert Sabin Way, Cincinnati, Ohio 45267-0528.
Liran
L
Oren
Department of Otolaryngology-Head and Neck Surgery, University of Cincinnati, 231 Albert Sabin Way, Cincinnati, Ohio 45267-0528.
Sid
S
Khosla
Department of Aerospace Engineering and Engineering Mechanics, University of Cincinnati, 799 Rhodes Hall, Cincinnati, Ohio 45221-0070.
Ephraim
E
Gutmark
D000818:Animals; D001696:Biomechanical Phenomena; D004285:Dogs; D005260:Female; D005931:Glottis / Q000033:anatomy & histology* / Q000502:physiology*; D007830:Larynx / Q000033:anatomy & histology* / Q000502:physiology*; D008297:Male; D010699:Phonation; D011312:Pressure; D013997:Time Factors; D014732:Vibration; D014827:Vocal Cords / Q000033:anatomy & histology / Q000502:physiology