ИСТИНА

The present work is dedicated to the modelling of the low-frequency part of the jetplate interaction noise in flight conditions. An analytical model used in the work is based on the scattering of jet near-filed hydrodynamic pulsations, represented in terms of azimuthal modes, by the plate trailing edge. Unlike the static case, in the presence of a coflow it is difficult to measure directly the azimuthal structure of the pressure in the jet nearfield. In the present work, we use the technique based on the hot-wire measurements on the jet axis. This approach allows measuring velocity fluctuations related to the axisymmetric mode. The agreement found between a parabolized stability equations (PSE) model and experimentally measured velocity fluctuations on the jet axis allows using the PSE approach for reconstruction of the pressure field of the axisymmetric mode in the vicinity of the plate trailing edge in static and flight conditions. These pressure characteristics are then used as input in the analytic jet-plate interaction noise model. It is shown that this analytic model informed by PSE-reconstructed pressure field is capable to capture the main features of low-frequency jet-plate interaction noise in the presence of co-flow.