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This study deals with the development of a numerical wire mesh screen model for the unsteady simulation of aeroacoustic configurations. Such devices are indeed of growing interest for practical app...

This study presents hybrid Reynolds-averaged Navier–Stokes/large-eddy simulations of the unsteady flow and noise-generation phenomena in the slat cove of a high-lift wing profile. These computations are part of a joint numerical/experimental aeroacoustics collaborative program dedicated to slat-flow analysis. A dedicated two-element wing profile (slat plus main body) has been designed to isolate slat noise from other possible sources (e.g., the flap), while minimizing mean flow deflection effects, to improve the fidelity of open-jet wind-tunnel measurements. The design of this two-element airfoil has been performed numerically, using an optimization process based on steady Reynolds-averaged Navier–Stokes calculations. This airfoil has been investigated experimentally at the Ecole Centrale de Lyon open jet facility. Unsteady zonal hybrid Reynolds-averaged Navier–Stokes/large-eddy simulations have been performed to provide a comprehensive description of the unsteady flow inside the slat cove, focusing on th...

A source-to-far-field computation procedure aimed at predicting the noise generated by rotor-stator fan interactions is presented here. Interaction noise sources are assessed using a three-dimensional Reynolds-averaged Navier-Stokes (RANS) code. A modal expansion is applied to the computational fluid dynamics (CFD) data, and a source model is used to link the CFD to an Euler code simulating the acoustic propagation. Far-field noise is classically obtained by means of a Kirchhoff integral. The source model is detailed and validated over a selected benchmark. Then the hybrid method is applied to a turbofan model, tested in the German-Dutch Wind Tunnel. Simulations are compared to boundary element method computations previously performed and used here to validate the no-flow solution. Interacting cut-on mode amplitude deduced from CFD output postprocessing is adjusted to fit in-duct measurements on the outer wall. The predicted radiation field is related to the directivity patterns measured at several axial positions upstream of the fan inlet and fairly good agreement is found using the RANS/Euler/Kirchhoff procedure.