Sound produced by vortex pairing in a forced subsonic axisymmetric jet using particle image velocimetry and vortex sound theory

The sound radiated by vortex pairing in a subsonic excited Jet is deduced from experimental data obtained by particle image velocimetry (PIV). We compare the performance of different formulations of vortex sound theory to predict the corresponding sound production. It is shown that assuming several times the conservation of the momentum and kinetic energy in the implementation of the vortex sound theory improves considerably the robustness of the prediction. In fact a reasonable prediction in agreement with numerical simulations is obtained while the basic data does not respect precisely these conservation laws.