High-Fidelity Flow and Noise Simulations of a Double-Stream Jet Installed in a T-Tail Configuration

This paper presents an investigation of the aerodynamic field and the acoustic signature of a mixed-stream coaxial jet, representative of a low-bypass ratio engine, installed on a T-tail configuration, typical of business jets. Numerical simulations and associated acoustic analysis have been performed by ONERA in the frame of the European collaborative project DJINN (Decrease Jet-Installation Noise), whose objectives are to design and assess noise reduction technologies for jet/wing interaction noise and demonstrate the applicability to complex industrial geometries. To this end, a high-fidelity Zonal-Detached Eddy Simulation is performed using the elsA software in its unstructured mode. The time-accurate evolution of the flows fields is used to reconstruct radiated noise: unsteady pressure, density and velocity are stored on porous surfaces surrounding the jet and the solid surfaces and are post-processed with the Ffowcs Williams and Hawkings (FWH) integral formulation, allowing for the radiation of the acoustic waves and the characterization of the radiated noise, via the code KIM. Spectral analysis of sensors located on the horizontal tail plane allows for an investigation of the acoustic loading, while far-field noise levels are evaluated and compared to available experimental data, yielding an agreement with a discrepancy around 1 dB on the OASPL.