Study of the acoustic oscillations by flows over cavities. Part 1. Internal flows

Xavier Amandolese (1) , Pascal Hémon (1, 2) , C. Regardin (1)

1 IAT-CNAM - Institut AéroTechnique
2 LadHyX - Laboratoire d'hydrodynamique

We present a study of acoustic oscillations induced by an internal airflow over a shallow and a deep cavity. The Kelvin-Helmholtz instability is interacting with an acoustic mode of the duct, leading to a resonance which produces a very high sound level. The influence of upstream boundary layer thickness and neck thickness is studied. Some results obtained by modifying the upstream lip shape, by crenel addition, are also given. It is also shown that the numerical simulations using a lattice-gas method give relatively good results by comparison with the experiments. Especially the resonance with the duct acoustics was qualitatively reproduced.

Xavier Amandolese, Pascal Hémon, C. Regardin. Study of the acoustic oscillations by flows over cavities. Part 1. Internal flows. 2002 International Mechanical Engineering Congress, Nov 2002, New Orleans, United States. pp.907-916. ⟨hal-01026146⟩