Aeroacoustic Analysis of a Two-Element Airfoil with a Leading Edge Slat Using Wall-Adapting Local Eddy-Viscosity Model for Large-Eddy Simulation
* Presenting author
This study presents the results of aeroacoustic simulations on a reference airfoil DU 91-W2-250. A passive-adaptive slat has been designed and optimised by German aerospace centre (DLR) as a part of the common German research project “Smart Blades 2”. Wall Adapting Local Eddy-viscosity model for large-eddy simulations are applied to provide a comprehensive description of the turbulent flow inside the slat cove and around the profile, focusing on the noise generation processes. Based on the simulation results, a detailed analysis of the flow is made. To predict far-field noise spectra, Curle’s acoustic analogy is implemented in the open source computational fluid dynamics framework OpenFOAM. This study is conducted for two slat configurations consisting of the completely open and closed slat. Different angles of attack are investigated. The free stream velocity is set to 27 m/s to obtain the same Reynolds number with measured wind tunnel aerodynamic data for comparison. For sensitivity studies and mesh independent studies, a various number of structured 3D grids with different resolutions are applied in the simulations. The flow results are in a good agreement with the experimental data. The sound pressure level spectrum for two slat configurations are presented and compared.