Prediction of flat plate self-noise

In this study, the accuracy of the computational methodology developed for prediction of turbulent flow noise at low Mach numbers is assessed for the flat plate self-noise. The far-field serf-noise and the wall-pressure field over the flat plate (chord=10cm, thickness=3mm, and span=30cm) are measured at Ecole Centrale de Lyon for a flow speed U_C=20m/s at zero angle of attack. The three-dimensional turbulent flow over the plate is computed by incompressible large eddy simulation (LES), while the near- and far-field acoustics are calculated by the linearized perturbed compressible equations (LPCE), coupled with the LES solutions. Comparisons are made for the wall pressure PSD spectra near the trailing-edge, the spanwise coherence function of the surface pressure, and the far-field sound pressure level spectrum. The computations agree well with the experiment. The tonal and broadband noise characteristics of the flat plate are also discussed.