Abstract:
Computational fluid dynamics (CFD) was used to obtain numerical solutions to laryngeal flow between simulated vibrating vocal folds. The unsteady Navier--Stokes equations were solved with a finite volume method using a nonuniform staggered grid. Vocal fold motion was simulated by sinusoidal variation of the inferior and superior glottal widths. The straight glottal walls oscillated between converging and diverging shapes, and the input airflow was sinusoidally varied from zero to a maximum and back to zero. Control variables included frequency of oscillation, Reynolds number, minimum glottal diameter, and the phase difference between the inferior and superior sections of the glottis. Results will be reported for Reynolds numbers of 1000 to 2000 and for oscillation frequencies of 100 to 200 Hz. Results with preliminary simulations (for which the glottal entry was fixed) produced periodic velocity and pressure fields throughout the whole laryngeal duct, and dominant effects of the flow acceleration and convection terms of the Navier--Stokes equations on the pressure gradient term. [Work supported by NIDCD Grant No. DC00831-04.]