Hear me out: A simplified model for voice production

Simulating airflow and vibrations within the throat is important for understanding pathological conditions that affect voice production. This process is extremely complex, making accurate models expensive and time-consuming to create.

By comparing 1D models, 3D models, and experimental measurements of vocal fold vibrations, Tsukasa Yoshinaga and Zhaoyan Zhang aimed to determine whether 1D models — which require orders of magnitude fewer computational resources than their 3D counterparts — are sufficient.

They found 1D models — models that represent variations in flow and pressure only between the lungs and the mouth, but not in left-right or front-back directions within the throat — work within normal vocalizations. They begin to deviate for lung pressures of about 1800 Pascals, which corresponds to loud voice production; normal speech usually falls between 600 and 1200. However, a 1D model might be insufficient if a person has asymmetries, growths, or trauma in their vocal folds.

“We did not expect the 1D model to perform so well in simulating more complex 3D vocal fold vibrations. However, we found that it can indeed predict them quite accurately, which saves a great deal of computational time,” said Yoshinaga. “This suggests that the method could be applied in clinical studies of voice disorders, where quick analysis of patients’ vocal fold vibration is important.”

With 1D models confirmed to be sufficient, the researchers’ goal is to apply them to analyze the physical mechanisms of pathological voice conditions.

“Because it is very difficult to observe the flow and sound fields in the human throat during speech, this simulation can serve as a powerful tool for predicting and analyzing normal and pathological voice conditions in the near future,” said Yoshinaga.

Source: “Evaluating the accuracy of one-dimensional glottal flow model in predicting voice production: comparison to experiments and three-dimensional flow simulations,” by Tsukasa Yoshinaga and Zhaoyan Zhang, Physics of Fluids (2025). The article can be accessed at https://doi.org/10.1063/5.0292598 .

This paper is part of the Flow and Phonation Collection, learn more here .