Acoustic characterisation of double-orifice configurations by means of an LES-SI approach

A numerical study of the aeroacoustic properties of a pair of orifices placed in a duct is presented. Two configurations with two different distances in between the orifices have been analysed to consider conditions with or without tonal noise sources. Large Eddy Simulations have been performed and validated with respect to experimental measurements for both aerodynamic and acoustic predictions. Data series from an acoustically excited LES have been post-processed through System Identification techniques to concurrently model noise sources and acoustic scattering. The model of the noise obtained has been used as to confirm the good prediction of the acoustic scattering.