Towards Acoustic Imaging for Digital Twin. Experimental Validation on a Rod-Airfoil Wind Tunnel Test

Numerical acoustic imaging extends the scope of array processing techniques to simulated datasets, for which virtual sensors gather extracted pressure to draw acoustic maps cleaned of any installation effects. Applied to CAA (computational aeroacoustics) signals, this ensemble of techniques turns out to be a suitable way to analyze the aeroacoustic behaviour of digital twins, with the help of both simulation and experimental means. To evaluate the validity of this strategy, an accurate agreement between the experimental measurement and its simulation is required. For this purpose, the assessment of numerical acoustic imaging techniques on classical benchmarks is appropriate. This paper details a unified approach to address acoustic imaging on the well studied rod-airfoil configuration. Comparisons between results obtained with both experimental and numerical datasets are carried out and include localization maps, acoustic power estimation and far-field directivities. Finally, the influence of installation effects and the ability of acoustic imaging to perform source separation are discussed.