A finite-element model of human phonation with fluid-structure interaction

• Applicants: Professor Dr.-Ing. Christoph Butenweg; Professor Dr.-Ing. Malte Kob; Professor Thoralf Niendorf, Ph.D.
• Subject Area: Fluid Mechanics ; Otolaryngology, Phoniatrics and Audiology
• Term: from 2008 to 2014
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 62604898

A fluid-structure interaction Finite-Element (FE) model of vocal fold function has been developed. First FE simulation results indicate that the shape of the glottal airway significantly influences the appearance of self-sustained oscillations of the vocal folds. MRI data which was obtained during in-vivo measurements have been used as the input for the geometry of the vocal folds.The elastic properties of the vocal folds of excised larynges were investigated in three dimensions using a linear skin rheometer (LSR), thus revealing details of the inhomogeneity and anisotropy of the vocal fold tissues. The repeatability of these measurements was improved through the construction and application of a dedicated stand for larynx samples which allows for precise configuration of vocal fold posturing and tension.The applicability of Magnet Resonance Imaging (MRI) measurements to characterize larynx geometry in-vivo and ex-vivo has been significantly improved by using novel triggering and high-field imaging methods.Validation methods for non-invasive observation of the glottal dynamics during phonation have been developed. Electroglottography (EGG) and acoustic signal analysis including voice range profiles have been applied to subjects that were capable of combined vocal fold and ventricular fold phonation yielding insight to the synchronous movement of both tissue structures. A novel multichannel electroglottograph and a method for spatial resolution of glottal movement have been further developed.The calculation of acoustic output using segmented mass models has been improved by application of a novel method for stable solution of arbitrarily segmented vocal folds.

• DFG Programme: Research Grants