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Updated: Jul 1, 2026
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Synthetic, Multi-Layer, Self-Oscillating Vocal Fold Model Fabrication
Published on: December 2, 2011
Pressure and velocity profiles in a static mechanical hemilarynx model
Fariborz Alipour1, Ronald C Scherer
1Department of Speech Pathology and Audiology, The University of Iowa, 334 WJSHC, Iowa City, Iowa 52242, USA. alipour@shc.uiowa.edu
The Journal of the Acoustical Society of America
|January 2, 2003
Summary
This study of a mechanical larynx model reveals vocal fold pressure patterns consistent with ductal flow. Downstream jet flow was turbulent, with consistent jet and turbulence intensity locations.
Area of Science:
- Biomechanics
- Fluid Dynamics
- Acoustics
Background:
- Understanding phonation mechanics is crucial for voice disorders.
- Hemilarynx models provide insights into glottal airflow and pressure dynamics.
Purpose of the Study:
- To investigate pressure and velocity profiles within a mechanical hemilarynx model.
- To analyze airflow characteristics during simulated phonation.
Main Methods:
- Utilized a hard plastic hemilarynx mechanical model with parallel walls.
- Employed pressure taps, differential pressure transducers, and hot-wire anemometry.
- Measured glottal gap using feeler gauges and verified duct uniformity with a laser system.
Main Results:
- Vocal fold surface pressure matched parallel duct theory.
- Opposite wall pressures were 8%-40% lower than transglottal pressure.
- Upstream velocity profiles were symmetric; downstream jet flow was turbulent.
- Jet front and turbulence intensity locations were consistent across different glottal gaps.
Conclusions:
- The mechanical model accurately reflects key aspects of glottal fluid dynamics.
- Turbulent jet formation occurs even with laminar upstream flow.
- Findings contribute to understanding the physical basis of voice production.
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