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The influence of glottal cross-section shape on theoretical flow models
Bo Wu1, Annemie Van Hirtum, Xavier Pelorson
1GIPSA-Lab, UMR CNRS 5216, Grenoble University, F-38031 Grenoble Cedex 1, France.
The Journal of the Acoustical Society of America
|August 10, 2013
Summary
Glottal flow models must consider cross-section shape for accuracy. Neglecting shape impacts boundary layers and pressure drop, making simplified models less reliable for phonation analysis.
Area of Science:
- Acoustics
- Fluid Dynamics
- Biomechanics
Background:
- Phonation models often use quasi-one-dimensional flow assumptions.
- The glottis's geometry significantly influences airflow during voice production.
Purpose of the Study:
- To analyze the impact of glottal cross-section shape on flow dynamics.
- To evaluate the accuracy of quasi-one-dimensional flow models in phonation.
Main Methods:
- Formulated a simplified flow model incorporating kinetic losses, viscosity, and cross-section shape.
- Analyzed flow through circular, rectangular, elliptical, and circular segment glottis shapes.
Main Results:
- Cross-section shape critically affects boundary layer development.
- Viscous contributions to pressure drop are significantly altered by glottal geometry.
- Quasi-one-dimensional models demonstrate inaccuracies due to shape neglect.
Conclusions:
- Glottal cross-section shape is a crucial factor in phonation modeling.
- Accurate phonation models require accounting for glottal geometry.
- Simplified flow models may be insufficient for precise voice production simulation.
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