In this study, we investigated the trailing-edge (TE) noise of a turbulent boundary layer (TBL) over a symmetric airfoil by examining the wall pressure spectra predicted by four different models, while systematically identifying and comparing key parameters and constants. We computed the TBL-TE noise-associated acoustic power spectral density using Amiet’s theory, which can be applied to propeller and rotor noise analysis. Numerical predictions of the one-third octave-band noise spectra for a NACA0012 airfoil exhibited excellent agreement with experimental data, and the far-field directivity pattern exhibited distinct side-lobe behavior at high frequencies. Based on these results, we conducted comparative analyses using the NACA0016 airfoil (commonly employed as a reference section in studies of vertical-axis wind turbine blades, horizontal control surfaces of underwater vehicles, and biomimetic airfoils) to assess far-field noise spectra, directivity, and noise scaling with flow velocity against established theoretical predictions.
Ryu et al. (Fri,) studied this question.