Large-eddy simulation for aerodynamic noise from high-lift device

Three dimensional time-accurate simulations on a leading-edge slat and wing combination were carried out by using a large-eddy simulation model (LES). To reduce the cost of LES simulations in terms of grid size/resolutions, a transverse boundary condition of a symmetry type was imposed at the sides of the model whilst keeping the slat spanwise extent to 18% of the main element 's chord. The cove region was decomposed into three zones in which the grid was generated separately. The model predicts the unsteady dynamics of the slat's flow field, and also those features of the flow that are related to the noise generation. Fluctuating properties of the flow were captured and analyzed for the aeroacoustics predictions. Special attention was paid to the pressure fluctuations (aerodynamic and acoustic pressures) inside the cove and over the slat surface, where the noise sources were initially based on. For the aeroacoustics computations the model based on Ffowes-Williams and Hawkings analogy has been used in conjunction with the LES solver.