Towards sibilant /s/ modelling: preliminary computational results
Résumé
The importance of turbulence in human speech sounds production is generally accepted in the case of fricatives. Nevertheless, this phenomenon is margely taken into account in physical modelling of speech production. The current study considers steady flow at a given Reynolds number Re = 4000. Large Eddy Simulation has been used to simulate the flow evolution in case of two dimensional geometries. The used geometrical and flow characteristics are severe simplifications of the human upper airways beyond the glottis. The impact of those typical geometries on the computed flow field is searched in order to detect the aeroacoustical sources producedby turbulent flow, crucial in /s/ production. The presence of the obstacle in a uniform channel and the curved pipe induce reversed flow. Nevertheless, the turbulence intensity, in case of the obstacle configuration does not correspond with turbulent flow, whereas the curve tends to give higher turbulent velocities along the curvature.