Abstract:

Results are presented describing an investigation of aerodynamic sources in the vocal tract. The expected contribution of this study is a new parametrization for fricative sources based on geometric and flow conditions. The flow in an idealized fricative geometry is computed numerically using a slightly compressible, Reynolds-averaged form of the Navier--Stokes equations. In this formulation, the aerodynamic sources of sound are simulated with minimal approximation. This approach has produced encouraging results for vowel sounds. Comparisons of the computational results with physical experiments using the same geometry have also been performed. The results shed light on the source mechanisms for fricative sounds and also show the need for the development of numerical boundary conditions which can simultaneously handle convective and propagative phenomena. [Research supported by NSF/ARPA IRI-9314946 and ARPA DAST 63-93-C-0064.]