Uncertainty quantification for the trailing-edge noise of a controlled-diffusion airfoil

Two deterministic incompressible flow solvers are coupled with a non-intrusive stochastic collocation method to propagate several aerodynamic uncertainties encountered in a standard trailing-edge noise experiment of a low-speed Controlled-Diffusion (CD) airfoil to predict the far-field noise. Reynolds-Averaged Navier-Stokes (RANS) and Large-Eddy Simulations (LES) are applied to the same restricted domain about the airfoil embedded in the potential core of the jet in the anechoic wind tunnel experiment. Both simulation methods provide the wall-pressure fluctuations near the airfoil trailing edge, which is then used in Amiet’s acoustic analogy for trailing-edge noise. In the RANS simulations, two different models are used to reconstruct the wall-pressure fluctuations: Rozenberg’s deterministic model directly based on integral boundary-layer parameters, and Panton & Linebarger’s statistical model based on the velocity field in the boundary layer. The nonintrusive stochastic model is solved with the inlet velocity profile as random variable. It is found as accurate as and much more efficient than a classical Monte Carlo simulation. The accuracy of the different methods to obtain the wall-pressure spectra is assessed by comparing their mean and standard deviations with experiment.