A Two-Dimensional Vocal Cord Model for Heavy Voice.

Abstract

To simulate heavy voice, we propose a new two-dimensional vocal cord model. The vocal cord model is composed of distributed springs and dampers covered with a massive elastic membrane. To simulate the effect of three-dimensional collision of the vocal cords using the two-dimensional model, we introduce two threshold values for the width between the two-dimensional vocal cords at which viscoelasticity changes. The two values divide the state of the three-dimensional vocal cord motion into three, i.e., the vocal cords are separated, contact partially, or contact completely. The vocal cord model is coupled with the fluid dynamic force based on the one-dimensional unsteady separable and reattachable flow theory which we previously presented. The numerical results show that the spectra of the sound pressure of heavy voice have high frequency components because of the inclusion of the high frequency components of the source sound which are induced by the collision of the vocal cords.