Trailing-edge noise prediction using the non-linear disturbance equations

Currently, the methods available for wind turbine noise prediction are either based on empirical data or require unrealistic computational costs. Although these methods are very valuable, a computationally efficient tool that is based on first principles is needed. The present research proposes a hybrid computational aeroacoustics approach for predicting turbulent-boundary-layer, trailing-edge (TBL-TE) noise. TBL-TE is of interest because it is a dominant source in the total broadband spectrum of wind turbine aerodynamic noise. The proposed method solves the Non-Linear Disturbance Equations (NLDE) for the unsteady flow field in the vicinity of the airfoil trailing edge, reducing computational time. Then, to calculate the noise radiated to a far-field location, the solution from the NLDE is saved and passed to the aeroacoustics propagation code, PSU-WOPWOP. Recent progress with the development of the NLDE flow solver, TANDEM (Turbulence And Noise using the Disturbance Equation Method) is presented. A qualitative assessment of this progress shows promising results. However, the complete noise prediction method is still in the development stage and is not fully validated in this work.