Computational Aeroacoustic Analsyis of Airfoil Sections in Deep Stall

The scope of this study is to explore the applicability of a CFD-CAA framework employing Delayed Detached Eddy Simulations(DDES) and the Ffowcs Williams and Hawkings (FW − H) analogy to obtain far-field noise predictions for the airfoil self-noise mechanism of separationstall noise, in particular for the deep stall regime. The CFD-CAA framework is first composed and validated successfully for a quasi-2D laminar flow test case. The focus is then shifted to analyzing the case of the NACA0021 in deep stall. Frequency and time-domain analyses are carried out to understand the influence of different sub grid scale (SGS) length scale definitions. The surface pressure fluctuations from the appropriate SGS length scale definition is propagated to the desired observer locations in the far-field with the help of the FW-H analogy. The far-field noise data is qualitatively compared with the available experimental data from previous studies.