title: Numerical study of the effects of inferior and superior vocal fold surface angles on vocal fold pressure distributions.
abstract: Vocal fold geometry plays an important role in human phonation. A wide range of inferior and superior vocal fold surface angles has been shown to be present during phonation [Nanayakkara, Master's thesis, Bowling Green State University, Bowling Green, OH (2005)]. This study explored how these angles affect pressure distributions on the vocal folds, and thus how they may affect phonation. The computational code FLUENT was used to obtain pressure distributions for laminar, incompressible flow. Eighteen inferior vocal fold surface angles and nineteen superior vocal fold surface angles were selected for three specific glottal angles, uniform 0 degrees, convergent 10 degrees, and divergent 10 degrees. Minimal glottal diameter (0.01 cm), transglottal pressure (8 cm H2O), and glottal entrance radius (0.15 cm) were held constant, and the glottal exit radius was constant for each glottal angle. Results suggest that the vocal fold surface pressures are independent of the inferior and superior vocal fold surface angles realistic for human phonation. These results suggest that, in contrast to the important effects of glottal entrance and exit radii, minimal diameter, and angle on intraglottal pressures, the inferior and superior vocal fold surface angles (excluding possible interactive effects with the false vocal folds) do not have an influence on the intraglottal pressures.
authors.affiliation: The Key Laboratory of Biomedical Information Engineering of Ministry of Education, and Department of Biomedical Engineering, School of Life Science and Technology, Xi'an Jiaotong University, Xi'an 710049, People's Republic of China.
authors.forename: Sheng
authors.initials: S
authors.lastname: Li
authors.forename: Ronald C
authors.initials: RC
authors.lastname: Scherer
authors.forename: Mingxi
authors.initials: M
authors.lastname: Wan
authors.forename: Supin
authors.initials: S
authors.lastname: Wang
authors.forename: Huihui
authors.initials: H
authors.lastname: Wu
mesh_terms: D016010:Binomial Distribution; D005931:Glottis / Q000502:physiology; D006801:Humans; D008954:Models, Biological; D010699:Phonation / Q000502:physiology*; D011312:Pressure; D014827:Vocal Cords / Q000033:anatomy & histology* / Q000502:physiology*