A co-axial subsonic unheated jet with and without a swept lifting wing at free-stream conditions from a recent jet–wing TsAGI experiment is considered. For computational modelling, Monotonically Integrated Large Eddy Simulations (MILES) are conducted based on the CABARET scheme which is implemented in a modern parallel unstructured-grid compressible Navier–Stokes computational code. The computational domain of the installed configuration includes a part of the nozzle and a wing section with round flow-fences present in the experiment to preclude the downwash effects. For the isolated jet, the same size of the computational domain is applied and two grid resolutions are considered to investigate the sensitivity of the current far-field noise predictions to the computational grid. The meanflow velocity profiles predicted downstream of the nozzle are compared with the flow data available. For far-field acoustic predictions, the Ffowcs Williams-Hawkings (FW-H) integral method is used. The Ffowcs Williams-Hawkings solutions correspond to a large closed permeable control surface with multiple closing disks at the outlet side set-up in accordance with the best practice to avoid pseudo sound in the acoustic modelling. The comparison of the acoustic predictions with the far-field spectra measured in the experiment for 30° and 90° observer angles to the jet flow are presented and discussed. It is shown that the current modelling robustly captures the same relative trends of the spectra behavior as observed in the experiment: while the presence of the wing does not lead to any significant change of sound spectrum in comparison with the isolated jet for 30°, there is a 8-10dB sound amplification due to the jet–wing interaction at 90° angle to the jet.

A classical problem on small scale fluctuations of the Rankine vortex in a compressible gas has been numerically simulated. Euler equations for a compressible gas have been solved by the CABARET method. Simulation results well predict the value of the eigenfrequency of the boundary fluctuations for the azimuthal harmonic n = 2 and almost coincide with the analytic solution. The value of the acoustic instability increment has been quantitatively predicted despite the fact that it is small and it has been revealed at a fluc tuation number higher than 100.

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