Solving for unsteady airflow in a glottal model with immersed moving boundaries

Sciamarella, Denisse; Quéré, Patrick Le

doi:10.1016/j.euromechflu.2007.06.004

Cited by 27 publications

(26 citation statements)

References 21 publications

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“…Flow separation is of interest during phonation as it significantly affects the pressure distribution on the VF surfaces. 3,34 Since the glottis may form a divergent channel in the open phase, the flow between the two VFs may separate from the medial surfaces. This phenomenon was studied in the numerical simulations of the stationary VF model 10 and in the experimental study of the glottal jet.…”

Section: B Glottal Jetmentioning

confidence: 99%

Analysis of flow-structure interaction in the larynx during phonation using an immersed-boundary method

Luo

Mittal

Bielamowicz

2009

The Journal of the Acoustical Society of America

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A recently developed immersed-boundary method is used to model the flow-structure interaction associated with the human phonation. The glottal airflow is modeled as a two-dimensional incompressible flow driven by a constant subglottal pressure, and the vocal folds are modeled as a pair of three-layered, two-dimensional, viscoelastic structures. Both the fluid dynamics and viscoelasticity are solved on fixed Cartesian grids using a sharp-interface immersed boundary method. It is found that the vibration mode and frequency of the vocal fold model are associated with the eigenmodes of the structures, and that the transition of the vibration mode takes place during onset of the sustained vibration. The computed glottal waveforms of the volume flux, velocity, and pressure are reasonably realistic. The glottal flow features an unsteady jet whose direction is deflected by the large-scale vortices in the supraglottal region. A detailed analysis of the flow and vocal fold vibrations is conducted in order to gain insights into the biomechanics of phonation.

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Section: B Glottal Jetmentioning

confidence: 99%

Analysis of flow-structure interaction in the larynx during phonation using an immersed-boundary method

Luo

Mittal

Bielamowicz

2009

The Journal of the Acoustical Society of America

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“…These include studies with fixed vocal folds (e.g. [12,13,14,15]), forced vocal fold oscillation [16,17,6,18,19,20,21,22,23] and models with the airflow fully coupled to elastic tissue oscillations [24,25,26,27,28,29,30]. Only a few of these computational studies [24,12,14,15,22] solve the flow field in 3D, and most of them on a static geometry.…”

Section: Previous Work In the Fieldmentioning

confidence: 99%

“…Some recent papers [37,14,15] claim that RANS approach for modeling of human phonation is inadequate and employ Large Eddy Simulations (LES). However, still many authors [16,24,18,25,19,20,13,28,21,30] use a "laminar" model, actually a Direct Numerical Simulation…”

Section: Previous Work In the Fieldmentioning

confidence: 99%

Computational aeroacoustics of human phonation

Šidlof

Zörner

2013

EPJ Web of Conferences

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The current paper presents a CFD model of flow past vibrating vocal folds coupled to an acoustic solver, which calculates the sound sources from the flow field in a hybrid approach. The CFD model is based on the numerical solution of 3D Navier-Stokes equations on a time-dependent domain, solved by cell-centered finite volume method. To capture the fine turbulent scales important for the acoustic source calculations, the equations are discretized and solved on large computational meshes up to 3.2M elements. The CFD simulations were run in parallel using domain decomposition method and OpenMPI implementation of the MPI standard. Aeroacoustic simulations are calculated in a separate step by Lighthill's acoustic analogy, which determines the acoustic sources based on the fluid field. This is done with the research code CFS++ which employs the finite element method (FEM).

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“…The flow picture through glottis and supraglottal tract used in the now classic two-mass model of Ishizaka and Flanagan [12] is the result of a considerable number of assumptions that, since then, have been thoroughly revisited and reconsidered. Much effort has been devoted in particular to correct the glottal flow model, which needs to capture flow separation and turbulent dissipation of the jet that is formed at the glottal exit [13,14]. On the other hand, the vocal tract is satisfactorily described in terms of linear acoustical properties.…”

Section: Background On Voice Production Modellingmentioning

confidence: 99%

“…Such an unsteady loss coefficient could be gleaned, for instance, from an in silico experiment [14], but this would forbid a discretionary choice for the valve dynamics, which should strictly mimic the dynamics used in the numerical simulation. Again, this work retains the standard option in basic water hammer practice and assumes that the valve discharge coefficient measured under steady flow conditions can be used in the unsteady pressure and flow analysis.…”

Section: The Valve Discharge Coefficientmentioning

confidence: 99%