Flow regimes at the output of oboe double-reeds
Résumé
Measurements of the quasistatic nonlinear characteristic curve for double reeds show systematic deviations from an elementary model of a reed instrument based on a spring model associated to a Bernoulli flow input into the reed. These deviations were previously explained by the pressure recovered by the flow as it expands in the conically divergent output duct of the reed. We will show measurements of the pressure recovery inside the reed as well as detailed flow profiles that can explain the different regimes observed for the pressure recovery (laminar and turbulent). An extension of these measurements to oscillating regimes allows us to observe some qualitative differences in the flow, suggesting an important influence of the dynamic terms in the Navier-Stokes equation in these kinds of regimes.