A simple hydrodynamic semi-continuum model of vocal-fold motion
Drew LaMar, Yingyong Qi, Jack X. Xin · The Journal of the Acoustical Society of America · 2002
Vocal-fold (VF) motion is a fundamental process in voice production, and is also a challenging problem for direct numerical computation because the VF dynamics depends on nonlinear coupling of airflow with the response of VFs, which undergo opening and closing, and induce internal flow variation. A traditional modeling approach makes use of Bernoulli’s law to treat the airflow, which is known to be inaccurate during VF opening. A new hydrodynamic semi-continuum system for VF motion is formulated. The airflow is modeled by a quasi-one-dimensional continuum aerodynamic system, and the VF by a classical lumped two-mass system. The reduced flow system contains the Bernoulli’s law as a special case, and is derivable from the two-dimensional compressible Navier–Stokes equations. Since no (quasi-)steady approximation is made, transients and rapid changes of solutions are captured, e.g. the double pressure peaks at opening and closing stages of VF motion in agreement with experimental data. It is demonstrated numerically, via a split-time finite difference method, that the system is simple, robust, and models in vivo VF airflows and oscillations efficiently. [Work partially supported by NSF and ARO.]