Velopharyngeal Closure Function Strategy in Articulation: Mechanical Dynamics Modeling of Air Flow in the Vocal Tract

Abstract

In this study, a numerical simulation of airflow while pronouncing a phrase /usuimisosiru/ with velopharyngeal closure based on cinematic volumetric data was performed. The results indicated that the air stream path was affected by the velopharyngeal closure. Principle morphological factors were selected to achieve articulation of the consonant, which was the constriction ratio of the velopharyngeal region and the narrowing of the oral cavity by the elevation of the tongue. The simplified velopharyngeal model was constructed based on the factors measured by using real morphological data. The results of the simulation using a simplified model indicated that a 20% and 30% constriction ratio of each region supplied the largest airflow magnitude from the nasal cavity and oral cavity.