Simulations of three-dimensional, self-oscillating vocal fold replicas with liquid-filled cavities

Synthetic, self-oscillating vocal fold replicas are used in bioreactors to study the response of injected cells to phono-mimetic vibrations. In this type of replica, cells are contained within a cylindrically shaped cavity that runs anterioposteriorly and that is located near the replica surface. During vocal fold replica flow-induced vibration, the cavity deforms, thereby subjecting the cells to a periodically varying stress field. The characteristics of this stress field are unknown, and experimental determination is not presently feasible. Therefore, in this research, numerical simulations of these self-oscillating, cell-containing synthetic replicas are studied. A three-dimensional vocal fold model containing a liquid-filled cavity, developed using the commercial software package ADINA, is described. The effects of glottal airflow are modeled using the mechanical energy equation to simulate the pressure distribution along the replica airway surface. The liquid-filled cavity is modeled through a fully coupled fluid-structure interaction solver, with the liquid region governed by the viscous, unsteady, three-dimensional Navier-Stokes equations. Estimates of the stress field within the cavity as well as the predicted influence of the cavity on replica vibration will be reported.