First International Conference on Spoken Language Processing (ICSLP 90)

Kobe, Japan
November 18-22, 1990

Glottal Flow Analysis Based on a Finite Element Simulation of a Two-Dimensional Unsteady Viscous Fluid

Hirohisa Iijima, Nobuhiro Miki, Nobuo Nagai

Research Institute of Applied Electricity, Hokkaido University, Sapporo, Japan

Unsteady viscous flows in two-dimensional static models of the glottis are numerically analyzed using a finite element method, and from those results, the physical characteristics of the glottal flow are considered. Since the glottal flow is sensitively affected by the shape of the vocal cord muscles, we make representative experiments on diverging, converging and uniform shaped glottal models in the case of wide diameter, and compare the flow fields between these models. After we briefly note the computing method for simulating the glottal flow numerically, equivalent impedance of the glottal flow is identified from the results of the finite element simulation. After that, pressure distributions along the vocal cord surfaces are discussed. The pressure distributions are almost accordant with Bernoulli's theorem and with the losses due to viscosity and nonlinearity. Furthermore, time-series of supraglottal pressure are shown and they are analyzed in the frequency domain. The supraglottal pressure would appear to be related to the rate of generation of the vortices, and to affect the acoustical propagation of the vocal tract.

Full Paper

Bibliographic reference.  Iijima, Hirohisa / Miki, Nobuhiro / Nagai, Nobuo (1990): "Glottal flow analysis based on a finite element simulation of a two-dimensional unsteady viscous fluid", In ICSLP-1990, 77-80.