Effects of the false vocal folds on sound generation by an unsteady glottal jet through rigid wall model of the larynx

In the present paper, the effects of the false vocal folds (FVFs) on sound generation induced by an unsteady glottal jet through a two-dimensional rigid wall model of the larynx are investigated by conducting numerical experiments. The glottal jets are simulated by solving the basic equations for a compressible viscous fluid based on the larynx model with and without the FVFs. The existence of the FVFs increases the amplitude of noise-like pressure fluctuation at the glottis and faraway from the glottis. Furthermore, the FVFs give rise to the broadbanding of the pressure spectrum throughout the fluid domain. These results indicate that the FVFs have a profound effect on the generation of broadband noise components in a speech wave.

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