Experimental validation of sound generated from flow in simplified vocal tract model of sibilant /s/

The coupled numerical simulation of flow and sound generation in a simplified vocal tract model of sibilant /s/ were validated with experimental measurements. The simplified model consists of incisors and four rectangular channels representing a throat, constriction, space behind the incisors, and lips. Velocity distribution and far-field sound were measured by a hot-wire anemometer and an acoustic microphone, respectively. Simulated amplitude of velocity fluctuation at the flow separation region was stabilized by increasing the grid resolution, and agreed with those of the measurement. Amplitude of sound pressure simulated by the low-resolution grids was larger than that of the high-resolution grids, indicating that calculation accuracy of velocity fluctuation at the separation region is required to simulate sound generation of the sibilant /s/.