Effect of Supraglottal Acoustics On Fluid-Structure Interaction During Human Voice Production

Abstract A hydrodynamic/acoustic splitting method was used to examine the effect of supraglottal acoustics on fluid-structure interactions during human voice production in a two-dimensional computational model. The accuracy of the method in simulating compressible flows in typical human airway conditions was verified by comparing it to full compressible flow simulations. The method was coupled with a three-mass model of vocal fold lateral motion to simulate fluid-structure interactions during human voice production. By separating the acoustic perturbation components of the airflow, the method allows isolation of the role of supraglottal acoustics in fluid-structure interactions. The results showed that an acoustic resonance between a higher harmonic of the sound source and the first formant of the supraglottal tract occurred during normal human phonation when the fundamental frequency was much lower than the formants. The resonance resulted in acoustic pressure perturbation at the glottis which was of the same order as the incompressible flow pressure and found to affect vocal fold vibrations and glottal flow rate waveform. Specifically, the acoustic perturbation delayed the opening of the glottis, reduced the vertical phase difference of vocal fold vibrations, decreased flow rate and maximum flow deceleration rate at the glottal exit; yet, they had little effect on glottal opening. The results imply that the sound generation in the glottis and acoustic resonance in the supraglottal tract are coupled processes during human voice production and computer modeling of vocal fold vibrations needs to include supraglottal acoustics for accurate predictions.

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Effect of Subglottic Stenosis on Vocal Fold Vibration and Voice Production Using Fluid–Structure–Acoustics Interaction Simulation

Applied Sciences ◽

10.3390/app11031221 ◽

2021 ◽

Vol 11 (3) ◽

pp. 1221

Author(s):

Dariush Bodaghi ◽

Qian Xue ◽

Xudong Zheng ◽

Scott Thomson

Keyword(s):

Flow Rate ◽

Vocal Fold ◽

Flow Resistance ◽

Signal To Noise Ratio ◽

Area Ratio ◽

Subglottic Stenosis ◽

Fluid Structure ◽

Voice Production ◽

Vocal Fold Vibration ◽

Glottal Flow

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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A Physical Model of the Vocal Folds

Advances in Bioengineering ◽

10.1115/imece2003-55061 ◽

2003 ◽

Author(s):

Scott L. Thomson ◽

Luc Mongeau ◽

Steven H. Frankel

Keyword(s):

Physical Model ◽

Vocal Fold ◽

Vocal Folds ◽

Operating Conditions ◽

Physical Models ◽

Length Scale ◽

Fluid Structure Interactions ◽

Fluid Structure ◽

Voice Production ◽

Flexible Polymer

Voice production is a result of the nonlinear, coupled interaction between laryngeal airflow and vocal fold tissue dynamics. Studying these fluid-structure interactions can contribute to the understanding of the mechanisms of speech production, leading to improved surgical, clinical, and pedagogical care. Aside from experiments using excised larynges (e.g., Berry et al., 2001) and a model of the superficial vocal fold layer (e.g., Chan et al., 1997), no studies appear to have been reported in which self-oscillating physical models were used that were similar to the human vocal folds in the following aspects: length scale, geometry, and dynamic and mechanical behavior. This paper describes a self-oscillating physical model designed to more closely represent the human vocal folds in terms of the above key parameters. The model was constructed using a flexible polymer casting and exhibited regular, self-sustained, large-amplitude oscillations at frequencies and operating conditions close to those found in human phonation. The model demonstrated potential for further studies involving laryngeal fluid-structure interactions.

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On the Mechanics of Phonation and Fluid-Structure Interactions in a Three Dimensional Vocal Fold Model

Volume 10: Mechanics of Solids and Structures, Parts A and B ◽

10.1115/imece2007-42185 ◽

2007 ◽

Author(s):

Somesh Khandelwal ◽

Thomas Siegmund ◽

Steve H. Frankel

Keyword(s):

Vibration Amplitude ◽

Vocal Fold ◽

Flow Model ◽

Three Dimensional ◽

The Self ◽

Elastic Response ◽

Fluid Structure Interactions ◽

Fluid Structure ◽

Structure Interaction ◽

Laminar Flow Model

It is hypothesized that the characteristics of vocal fold self oscillation is dependent on the nonlinearity of the solid structure i.e. the tissue. Studies of fluid structure interaction are conducted for three dimensional larynx models. Simulations were performed using the codes FLUENT and ABAQUS coupled by the code MpCCI. For the air an unsteady, laminar flow model was considered. Visco-hyperelasticity was used to characterize the solid domain representing the tissue structure. The computational model is used to conduct a parametric study on the self-oscillation response of the model with focus on the influence of the non-linearity in the hyperelastic response. Individual computations were compared by documenting the variation of the total energy of the structure. It is demonstrated that dissipation in the flow as well as the non-linearity in the elastic response all interact to stabilize or destabilize the vibration amplitude.

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A Deep Neural Network Based Glottal Flow Model for Predicting Fluid-Structure Interactions during Voice Production

Applied Sciences ◽

10.3390/app10020705 ◽

2020 ◽

Vol 10 (2) ◽

pp. 705

Author(s):

Yang Zhang ◽

Xudong Zheng ◽

Qian Xue

Keyword(s):

Neural Network ◽

Flow Resistance ◽

Deep Neural Network ◽

Shape Function ◽

Resistance Coefficient ◽

Prediction Performance ◽

Fluid Structure Interactions ◽

Fluid Structure ◽

Voice Production ◽

Glottal Flow

This paper proposes a machine-learning based reduced-order model that can provide fast and accurate prediction of the glottal flow during voice production. The model is based on the Bernoulli equation with a viscous loss term predicted by a deep neural network (DNN) model. The training data of the DNN model is a Navier-Stokes (N-S) equation-based three-dimensional simulation of glottal flows in various glottal shapes generated by a synthetic shape function, which can be obtained by superimposing the instantaneous modal displacements during vibration on the prephonatory geometry of the glottal shape. The input parameters of the DNN model are the geometric and flow parameters extracted from discretized cross sections of the glottal shapes and the output target is the corresponding flow resistance coefficient. With this trained DNN-Bernoulli model, the flow resistance coefficient as well as the flow rate and pressure distribution in any given glottal shape generated by the synthetic shape function can be predicted. The model is further coupled with a finite-element method based solid dynamics solver for simulating fluid-structure interactions (FSI). The prediction performance of the model for both static shape and FSI simulations is evaluated by comparing the solutions to those obtained by the Bernoulli and N-S model. The model shows a good prediction performance in accuracy and efficiency, suggesting a promise for future clinical use.

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Effect of Longitudinal Variation of Vocal Fold Inner Layer Thickness on Fluid-Structure Interaction During Voice Production

Journal of Biomechanical Engineering ◽

10.1115/1.4041045 ◽

2018 ◽

Vol 140 (12) ◽

Cited By ~ 4

Author(s):

Weili Jiang ◽

Qian Xue ◽

Xudong Zheng

Keyword(s):

Computational Model ◽

Layer Thickness ◽

Vibration Amplitude ◽

Vocal Fold ◽

Fluid Structure Interaction ◽

Thickness Variation ◽

Longitudinal Variation ◽

Fluid Structure ◽

Voice Production ◽

Structure Interaction

A three-dimensional fluid-structure interaction computational model was used to investigate the effect of the longitudinal variation of vocal fold inner layer thickness on voice production. The computational model coupled a finite element method based continuum vocal fold model and a Navier–Stokes equation based incompressible flow model. Four vocal fold models, one with constant layer thickness and the others with different degrees of layer thickness variation in the longitudinal direction, were studied. It was found that the varied thickness resulted in up to 24% stiffness reduction at the middle and up to 47% stiffness increase near the anterior and posterior ends of the vocal fold; however, the average stiffness was not affected. The fluid-structure interaction simulations on the four models showed that the thickness variation did not affect vibration amplitude, glottal flow rate, and the waveform related parameters. However, it increased glottal angles at the middle of the vocal fold, suggesting that vocal fold vibration amplitude was determined by the average stiffness of the vocal fold, while the glottal angle was determined by the local stiffness. The models with longitudinal variation of layer thickness consumed less energy during the vibrations compared with the constant layer thickness one.

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Vibroacoustical Analysis of Flow in Pipes

Volume 3B: 15th Biennial Conference on Mechanical Vibration and Noise — Acoustics, Vibrations, and Rotating Machines ◽

10.1115/detc1995-0472 ◽

1995 ◽

Author(s):

J. Charley ◽

F. Carta ◽

G. Caignaert

Keyword(s):

Transfer Matrix ◽

Matrix Model ◽

Flow Rate ◽

Fluid Structure Interactions ◽

Acoustic Intensity ◽

Fluid Structure

Abstract This paper is concerned with the study of pressure and flow rate fluctuations propagation within ducts. A new transfer matrix model for a pipe taking into account the fluid-structure interactions effects is presented and compared to other formulations; significant gains have been realized. An extension of acoustic intensity technique using four transducers is presented.

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Fluid-Structure Interactions in Low-Reynolds-Number Flows

10.1039/9781782628491 ◽

2015 ◽

Cited By ~ 14

Keyword(s):

Reynolds Number ◽

Low Reynolds Number ◽

Fluid Structure Interactions ◽

Fluid Structure ◽

Low Reynolds Number Flows ◽

Low Reynolds ◽

Reynolds Number Flows

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Assessment of Tongue Position and Laryngeal Height in Two Professional Voice Populations

Journal of Speech Language and Hearing Research ◽

10.1044/2019_jslhr-19-00164 ◽

2020 ◽

Vol 63 (1) ◽

pp. 109-124

Author(s):

Carly Jo Hosbach-Cannon ◽

Soren Y. Lowell ◽

Raymond H. Colton ◽

Richard T. Kelley ◽

Xue Bao

Keyword(s):

Vocal Fold ◽

Vocal Tract ◽

Current Knowledge ◽

Acoustic Resonance ◽

Contact Dynamics ◽

Voice Disorder ◽

Music Program ◽

Tongue Position ◽

Singer Groups ◽

Professional Voice

Purpose To advance our current knowledge of singer physiology by using ultrasonography in combination with acoustic measures to compare physiological differences between musical theater (MT) and opera (OP) singers under controlled phonation conditions. Primary objectives addressed in this study were (a) to determine if differences in hyolaryngeal and vocal fold contact dynamics occur between two professional voice populations (MT and OP) during singing tasks and (b) to determine if differences occur between MT and OP singers in oral configuration and associated acoustic resonance during singing tasks. Method Twenty-one singers (10 MT and 11 OP) were included. All participants were currently enrolled in a music program. Experimental procedures consisted of sustained phonation on the vowels /i/ and /ɑ/ during both a low-pitch task and a high-pitch task. Measures of hyolaryngeal elevation, tongue height, and tongue advancement were assessed using ultrasonography. Vocal fold contact dynamics were measured using electroglottography. Simultaneous acoustic recordings were obtained during all ultrasonography procedures for analysis of the first two formant frequencies. Results Significant oral configuration differences, reflected by measures of tongue height and tongue advancement, were seen between groups. Measures of acoustic resonance also showed significant differences between groups during specific tasks. Both singer groups significantly raised their hyoid position when singing high-pitched vowels, but hyoid elevation was not statistically different between groups. Likewise, vocal fold contact dynamics did not significantly differentiate the two singer groups. Conclusions These findings suggest that, under controlled phonation conditions, MT singers alter their oral configuration and achieve differing resultant formants as compared with OP singers. Because singers are at a high risk of developing a voice disorder, understanding how these two groups of singers adjust their vocal tract configuration during their specific singing genre may help to identify risky vocal behavior and provide a basis for prevention of voice disorders.

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