Effect of Trailing-Edge Bevel Angle on the Sound Generation of a Flat Plate

An experimental study was conducted to investigate the effect of the trailing-edge bevel angle on the noise radiated from the trailing-edge and the corresponding hydrodynamic field. The Reynolds number based on the length of the adjustable bevel part length was Re = 1.4x105. Results are presented for bevel angles 0◦ < α < 28◦. The hydrodynamic field is characterized by steady and unsteady pressure measurements and hot-wire measurements. Radiated noise from the trailing-edge was determined with a beamforming array. The results demonstrate that the increase in the bevel angle increases the radiated noise up to α = 8◦ and the far-field noise level starts decreasing beyond the bevel angle of α = 8◦. The corresponding hydrodynamic field on the beveled part of the trailing-edge displays an accelerated flow region with an accompanied increase in pressure coefficient values. In general, the energy spectra of the unsteady surface pressure fluctuation results indicates a slight broadband energy increase as the bevel angle increases for an attached flow. Moreover, the velocity-pressure coherence analysis reveals a significant reduction for the increased bevel angle which may be related to reduced size of the coherent structures indicated by the stream-wise coherence analysis.