A study of voice production characteristics of astronuat speech during Apollo 11 for speaker modeling in space

An in-house 3D fluid–structure–acoustic interaction numerical solver was employed to investigate the effect of subglottic stenosis (SGS) on dynamics of glottal flow, vocal fold vibration and acoustics during voice production. The investigation focused on two SGS properties, including severity defined as the percentage of area reduction and location. The results show that SGS affects voice production only when its severity is beyond a threshold, which is at 75% for the glottal flow rate and acoustics, and at 90% for the vocal fold vibrations. Beyond the threshold, the flow rate, vocal fold vibration amplitude and vocal efficiency decrease rapidly with SGS severity, while the skewness quotient, vibration frequency, signal-to-noise ratio and vocal intensity decrease slightly, and the open quotient increases slightly. Changing the location of SGS shows no effect on the dynamics. Further analysis reveals that the effect of SGS on the dynamics is primarily due to its effect on the flow resistance in the entire airway, which is found to be related to the area ratio of glottis to SGS. Below the SGS severity of 75%, which corresponds to an area ratio of glottis to SGS of 0.1, changing the SGS severity only causes very small changes in the area ratio; therefore, its effect on the flow resistance and dynamics is very small. Beyond the SGS severity of 75%, increasing the SGS severity, leads to rapid increases of the area ratio, resulting in rapid changes in the flow resistance and dynamics.

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Impact of the Sub-Grid Scale Turbulence Model in Aeroacoustic Simulation of Human Voice

Applied Sciences ◽

10.3390/app11041970 ◽

2021 ◽

Vol 11 (4) ◽

pp. 1970

Author(s):

Martin Lasota ◽

Petr Šidlof ◽

Manfred Kaltenbacher ◽

Stefan Schoder

Keyword(s):

Sound Propagation ◽

Vocal Tract ◽

Vocal Folds ◽

Equation Model ◽

Voice Production ◽

Human Voice ◽

Large Eddy ◽

Aeroacoustic Simulation ◽

Scale Turbulence ◽

The One

In an aeroacoustic simulation of human voice production, the effect of the sub-grid scale (SGS) model on the acoustic spectrum was investigated. In the first step, incompressible airflow in a 3D model of larynx with vocal folds undergoing prescribed two-degree-of-freedom oscillation was simulated by laminar and Large-Eddy Simulations (LES), using the One-Equation and Wall-Adaptive Local-Eddy (WALE) SGS models. Second, the aeroacoustic sources and the sound propagation in a domain composed of the larynx and vocal tract were computed by the Perturbed Convective Wave Equation (PCWE) for vowels [u:] and [i:]. The results show that the SGS model has a significant impact not only on the flow field, but also on the spectrum of the sound sampled 1 cm downstream of the lips. With the WALE model, which is known to handle the near-wall and high-shear regions more precisely, the simulations predict significantly higher peak volumetric flow rates of air than those of the One-Equation model, only slightly lower than the laminar simulation. The usage of the WALE SGS model also results in higher sound pressure levels of the higher harmonic frequencies.

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Voluntary intake of silages in dairy cows depending on chemical composition and in vitro gas production characteristics

Livestock Science ◽

10.1016/j.livsci.2006.06.013 ◽

2007 ◽

Vol 106 (1) ◽

pp. 47-56 ◽

Cited By ~ 13

Author(s):

M. Hetta ◽

J.W. Cone ◽

G. Bernes ◽

A.-M. Gustavsson ◽

K. Martinsson

Keyword(s):

Chemical Composition ◽

Dairy Cows ◽

Gas Production ◽

In Vitro Gas Production ◽

Voluntary Intake ◽

Production Characteristics

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Correlates of Turbulent Noise Production for Speech

Journal of Speech and Hearing Research ◽

10.1044/jshr.1001.133 ◽

1967 ◽

Vol 10 (1) ◽

pp. 133-140 ◽

Cited By ~ 5

Author(s):

Thomas J. Hixon ◽

Fred D. Minifie ◽

Charles A. Tait

Keyword(s):

Sound Pressure Level ◽

Sound Pressure ◽

Power Laws ◽

Pressure Level ◽

Air Pressure ◽

Voice Production ◽

Volume Rate ◽

Intraoral Air Pressure ◽

Noise Production ◽

Parameters Of Interest

Intraoral air pressure, volume rate of airflow, and sound pressure level were measured during /∫/ and /s/ productions of two speakers. In addition numerical estimates of the loudness of the productions were made by each speaker and by a group of judges. The power laws governing the relations among the parameters of interest are discussed and the results are compared with available data on voice production.

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