Lip vibration self-sustains through Bernoulli pressure and elastic recoil

Evidence

Soon after they are momentarily shut, the folds are forced open again by air pressure and flow from the lungs. As they are blown open, the folds acquire some velocity and momentum, causing them to continue to open, but like an oscillator, they resist stretching with an opposing tension. They reach a maximum opening and stretch, but the ensuing elastic rebound causes them to close, and the cycle then repeats. It is often stated that the Bernoulli effect (pressure is lower where air is flowing faster, as it is when it passes by the folds) is responsible for their closing, but this only part of the effect, probably more important for soft singing. The role of the elasticity and acquired momentum of the membranes (that is, the oscillator characteristics) involved should not be overlooked. Like an oscillator, the folds under a given tension and held at a given separation have a resonance frequency, which becomes the drive frequency for the vocal tract. For conversation, this drive frequency averages 100 to 125 Hz for males and 210 Hz for females; children average over 300 Hz. — Eric J. Heller, Why You Hear What You Hear- An…, 1661 (#contradicts, via linked claim)

Categorization

• XREF: connects to: Elastic recoil and momentum, not Bernoulli effect, mainly close the vocal folds; Elastic lips sustain oscillation only when energy is continuously input; Bernoulli’s airflow across curved lips initiates their vibration (+3 more)

Related

• Bernoulli’s airflow across curved lips initiates their vibration (similarity 0.97)
• Elastic recoil and momentum, not Bernoulli effect, mainly close the vocal folds (similarity 0.96)
• The Bernoulli effect is a wrong explanation for vocal fold vibration (similarity 0.93)
• The vocal folds vibrate via pressure changes from curved airflow, not the Bernoulli effect (similarity 0.89)
• A sinusoidal vocal fold wave would make speech impossible (similarity 0.89)
• Elastic lips and vocal folds self-oscillate once energy input begins. (similarity 0.86)
• Elastic lips sustain oscillation only when energy is continuously input (similarity 0.85)
• Curved-surface airflow, not the Bernoulli effect, drives lip vibration. (similarity 0.84)
• Lift on curved surfaces comes from a pressure gradient, not the Bernoulli effect (similarity 0.82)
• The Bernoulli effect couples airflow velocity to reduced pressure at constrictions (similarity 0.80)
• Lips only begin oscillating as a reed once airflow passes a threshold (similarity 0.80)
• Vocal fold oscillation frequency is predictable without invoking aerodynamic forces (similarity 0.78)
• Buzzing lips generate many harmonics that resonance then shapes before radiating. (similarity 0.78)

Broader Connections

• The Bernoulli effect is a wrong explanation for vocal fold vibration #contradicts (0.90) — Eric J. Heller, Why You Hear What You Hear- An…, 1661
• The Bernoulli effect couples airflow velocity to reduced pressure at constrictions #expands (0.85)
• Lift on curved surfaces comes from a pressure gradient, not the Bernoulli effect #qualifies (0.80)