Modelling and measurement of the acoustic input impedance of a vibrating cylindrical membrane tube

Abstract

The influence of the wall vibrations of a musical instrument on tonal quality remains an open question. This Mater's thesis deals with the question of fluid-structure interaction in a wind instrument. It focuses on the particular case of the behaviour of membranes. A vibroacoustic model of a membrane waveguide is presented and the results of several measurements done with a rubber cylindical tube are discussed. The model is then competed by the effect of a static tension applied at one end of the tube, aiming to rigidify the walls. Celerity curves and acoustic input impedance diagrams from the model and from the experiments are plotted. The study shows that some frequency ranges are specific to a membrane waveguide and that the tension has no effect.