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Updated: Aug 8, 2026
09:58
Investigating the Three-dimensional Flow Separation Induced by a Model Vocal Fold Polyp
Published on: February 3, 2014
Theoretical analysis of maximum flow declination rate versus maximum area declination rate in phonation
1The University of Iowa, Iowa City, USA. ititze@dcpa.org
Summary
This study reveals how vocal fold movement and vocal tract inertance influence the maximum flow declination rate (MFDR), a key factor in vocal intensity. Understanding these dynamics offers insights into voice control for speakers and singers.
Area of Science:
- Acoustics
- Biomechanics
- Speech Science
Background:
- Maximum flow declination rate (MFDR) correlates with vocal intensity.
- MFDR is influenced by maximum area declination rate (MADR) and vocal tract air column inertia.
Purpose of the Study:
- To theoretically investigate the contributions of air inertance and MADR to MFDR.
- To elucidate the relationship between glottal dynamics and vocal intensity control.
Main Methods:
- Utilized a simplified computational model of vocal fold kinematics.
- Computed glottal area function and glottal flow interactively with lumped vocal tract parameters (resistance, inertive reactance).
Main Results:
- MADR is primarily determined by the ratio of vibrational amplitudes of the lower to upper vocal fold margins.
- A rule was developed linking MFDR to vibrational amplitude ratio and vocal tract inertance.
- Adduction, vertical phase difference, and prephonatory convergence have minor effects on MADR.
Conclusions:
- Speakers and singers possess diverse strategies for vocal intensity control.
- Some intensity control methods involve greater source-filter interaction than others.
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