5aMU6. Time-domain simulation of aeroacoustic sources in flutelike instruments.

Session: Friday Morning, December 6

Time: 9:50

Author: Marc-Pierre Verge
Location: Laboratoire d'Acoustique Musicale, CNRS, Universite de Paris VI, Ministere de la Culture, case 161, 4 Pl. Jussieu, 75252 Paris Cedex 05, France
Author: A. Hirschberg
Location: Technische Universiteit Eindhoven, Postbus 513, 5600 Eindhoven, The Netherlands


The sounding mechanism of flutelike instruments is based on the oscillations of an airjet on each side of the labium. This jet motion provides the ``drive'' which enables the maintenance of the acoustic oscillations in the resonator of the instrument. Sound is also produced by two other aeroacoustic sources, namely, vortex shedding at the edge of the labium and turbulence in the mouth of the instrument. Vortex shedding is crucial since it represents the main nonlinear amplitude limiting mechanism for the fundamental of the acoustic oscillations. The shedding of vortices also contributes to generate high frequencies in the spectrum and therefore determines the tone of the instrument. Turbulence in the mouth produces noise which constitutes, although it does not contribute fundamentally to the functioning of the instrument, an essential component of its tone. Simple and efficient hydrodynamic representations of these complex phenomena are presented. The influence on the tone produced by the instrument of the mouth geometry, which accounts for the work of the instrument maker, and the playing conditions is also discussed. These features are included in a one-dimensional simulation model of flutelike instruments which can be used for real-time sound synthesis.

ASA 132nd meeting - Hawaii, December 1996