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Updated: Sep 21, 2025
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Hemi-laryngeal Setup for Studying Vocal Fold Vibration in Three Dimensions
Published on: November 25, 2017
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Experimental study on the quasi-steady approximation of glottal flows
Takuto Honda1, Mayuka Kanaya1, Isao T Tokuda1
1Graduate School of Science and Engineering, Ritsumeikan University, Noji-higashi, Kusatsu, Shiga 525-8577, Japan.
The Journal of the Acoustical Society of America
|June 1, 2022
Summary
The quasi-steady approximation for glottal flow is valid for modeling vocal fold oscillations. Time-varying glottal flow behaves like steady flow, simplifying vocal fold models.
Area of Science:
- Acoustics
- Fluid Dynamics
- Biomechanics
Background:
- The quasi-steady approximation simplifies glottal flow modeling in vocal fold dynamics.
- Accurate modeling is crucial for understanding voice production and pathologies.
Purpose of the Study:
- To experimentally validate the quasi-steady approximation for glottal flow.
- To investigate intraglottal pressure under time-varying flow conditions.
Main Methods:
- Used a scaled-up static vocal fold model with symmetric and oblique configurations.
- Measured intraglottal pressure with sinusoidally modulated flow rates (2 and 10 Hz).
- Compared pressure profiles and air-jet separation points between steady and time-varying flows.
Main Results:
- Intraglottal pressure profiles were indistinguishable between steady and time-varying flows with matched subglottal pressure.
- Air-jet separation points did not differ significantly between steady and time-varying flow conditions.
- The quasi-steady approximation holds for non-critical glottal configurations.
Conclusions:
- Time-varying glottal flow can be approximated as a series of steady states for vocal fold modeling.
- This finding supports the use of the quasi-steady approximation in voice production research.
- The study's conclusions are applicable within the range of normal vocalization frequencies, excluding glottal closure.
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