Fluid–structure instabilities in the axial balancing system of a turbo-pump

This article is devoted to the experimental and theoretical modelling of a fluid structure instability that affects the axial balancing system cavities of spatial turbo-pumps. After having explained the design of the laboratory experiment that mimics the real industrial set-up, we describe the observation of the instability that emerges due to the coupling of acoustic modes of a fluid cavity with the deformations of a metallic disc that closes the cavity when a flow passes through the system.