Rod-Airfoil Wind Tunnel Testing, a Classic Revisited: Validation of Aeroacoustics Numerical Modelling in the Near and Far Field

Whenever numerical simulation approaches must be validated, it is required to correlate them either with test or with analytical solutions. Due to the turbulent noise generation mechanisms, such a quantitative verification in aeroacoustics is usually limited to comparisons with test data. In this paper we attempt to demonstrate how aeroacoustics simulation can be compared with a test of a rod-airfoil experiment. Therefore, the 2004 experiment from Jacob et al. was revisited and equipped with additional microphones to allow a validation of the numerical method in the near and far field. We demonstrate that near field measurements obtained with surface microphones can only deliver insights into the validity of the simulated turbulent pressure fluctuations and that it is required to incorporate an approximation of the microphones’ response function in the simulation. In the far-field, we demonstrate that modelling installation effects is important in order to capture all details of a spectrum. In simulations of real-world scenarios, it is often required to compromise accuracy and computational costs. In order to explore these aspects we show how different turbulence models and grid resolutions impact the quality of the results and outline how to setup efficient simulations that are still accurate.