Noise source, length and time scale distributions in installed jets with a flight stream

Installed jet noise sources are 3D in nature. Large-Eddy Simulation (LES) and hybrid LES-Reynolds-Averaged Navier-Stokes (LES-RANS), provides a method to increase understanding of influences on the noise produced. Here, using LES-RANS data, a coaxial nozzle with an ultra-high bypass-ratio is studied with and without a wing-flap geometry and with a flight stream. An isolated and installed jet with a flap deflection of 14 degrees are contrasted. Far-field sound is in agreement with measurements at a variety of locations. Sound sources, length and time scales are presented using second and fourth order space-time correlations. An automated system used for this is outlined. The installed case generates strong sources downstream of the flap trailing edge and additional mixing noise in the outer shear layer. The extracted data may be used in future to inform rapid modelling of jet noise at reduced cost