摘要: The trailing edge noise (TEN) of a NACA 0012 airfoil at an angle of attack of α = 4° is predicted by a direct hybrid CFD/CAA method for a solid and a poro-serrated trailing edge. The simulations are conducted for a free-stream Mac... 展开 The trailing edge noise (TEN) of a NACA 0012 airfoil at an angle of attack of α = 4° is predicted by a direct hybrid CFD/CAA method for a solid and a poro-serrated trailing edge. The simulations are conducted for a free-stream Mach number of M_∞ = 0.11 and a chord based Reynolds number of Re_c = 1 x 10~6. The turbulent flow field is obtained by large-eddy simulation (LES), from which the vortex noise source is extracted and used as an acoustic source for the acoustic perturbation equations (APE) to determine the acoustic field. For the poro-serrated trailing edge, the systems of equations describing the flow and acoustic field are volume averaged and extended with homogenized models for the porous media. The turbulent flow field is analyzed to better understand the noise sources and to evaluate the aerodynamic performance of the trailing edge configurations. Acoustic results are presented in form of frequency spectra and directivity plots, which show an attenuation of TEN in the low frequency range, while the sound pressure level is enhanced for higher frequencies. 收起