Glottal impedance based on a finite element analysis of two-dimensional unsteady viscous flow in a static glottis

Unsteady viscous flows in various static models of the glottis are numerically simulated using a finite-element method, and parameters of the electrically equivalent impedances in the models are determined. Different shapes of the static models, which are obtained by varying the angle and diameter of the glottis, produce flow patterns quite different from each other. Really complicated flow patterns have been obtained with the help of appropriate preprocessing/postprocessing software. The equivalent glottal impedance parameters are evaluated. The equivalent resistance values are compared with those derived by previously proposed formulas, and the equivalent inductance values are compared with the analytic solution derived from the Navier-Stokes equations. The present results closely approximate real flow measurements already reported, thus indicating that the numerical method approximates the real phenomena and is therefore useful for the analysis of vocal sources