The human phonation is characterized by periodical oscillations of the vocal folds with a complete glottis closure. In contrast, a glottal insufficiency (GI) represents an oscillation without glottis closure resulting in a breathy and weak voice. In this study, flow-induced oscillations of silicone vocal folds were modeled with and without glottis closure. The measurements comprised the flow pressure in the model, the generated sound, and the high-speed footage of the vocal fold motion. The analysis revealed that the sound signal for vocal fold oscillations without closure exhibits a lower number of harmonic tones with smaller amplitudes compared to the case with complete closure. The time series of the pressure signals showed small and periodical oscillations occurring less frequently and with smaller amplitude for the GI case. Accordingly, the pressure spectra include fewer harmonics similar to the sound. The analysis of the high-speed videos indicates that the strength of the pressure oscillations correlates with the divergence angle of the glottal duct during the closing motion. Physiologically, large divergence angles typically occur for a pronounced mucosal wave motion with glottis closure. Thus, the results indicate a correlation between the intensity of the mucosal wave and the development of harmonic tones.

中文翻译：

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分析声门闭合和不闭合时发声时的音调。

人的发声的特征在于声门的周期性振荡以及声门完全闭合。相反，声门功能不全（GI）表示没有声门闭合的振动，导致呼吸音弱。在这项研究中，有声门闭合和无声门闭合都模拟了流动引起的硅树脂声带振荡。测量包括模型中的流动压力，所产生的声音以及声带运动的高速镜头。分析表明，与完全闭合的情况相比，没有闭合的人声折叠振动的声音信号显示出较少数量的谐波音，振幅较小。压力信号的时间序列显示出较小的周期性振荡，在GI情况下发生频率较小，幅度较小。因此，压力谱中包含与声音类似的较少谐波。高速视频的分析表明，在关闭运动期间，压力振荡的强度与声门导管的发散角相关。在生理上，对于声门闭合的明显粘膜波运动，通常会出现较大的发散角。因此，结果表明在粘膜波的强度和谐波音的发展之间的相关性。