A Study of Self-Oscillation of a Model Vocal Fold System by Digital Image Correlation

Abstract

The understanding of the mechanics of the deformation behavior of vocal folds during flow-induced vibration is of central interest in studies of voice production. We have developed physical models of the vocal folds and connected such models to a flow supply system. The self-sustained oscillation of the vocal folds during phonation experiments is investigated using digital image correlation (DIC) techniques enabled through the use of a high-speed digital camera. A laser Doppler velocimeter was used to independently verify results from the DIC. The study reports on vibratory motion of the superior surface of the model vocal folds, and documents strain fields, and principal strains on that surface. From measured strains and the incompressibility assumption, the corresponding stress fields are computed. Strains on the vocal fold superior surface are quantified in dependence of varying subglottal pressures and flow rates.