This paper is concerned with the noise generation mechanism from blunt trailing edges and the use of porous treatments as a mean to reduce the radiated noise and stabilizing the wake flow. Experiments have been carried out for flat plates with and without porous trailing edge for a wide range of Reynolds numbers. To gain a better understanding of the underlying physics of the noise generation mechanism and the effects of porous trailing edges, data has been collected for steady and unsteady aerodynamic forces, hotwire measurements within the boundary layer and the wake region and the boundary layer surface pressure measurement. It has been seen that the use of porous material can significantly reduce the unsteady drag fluctuations, stabilize the boundary layer, lessen the surface pressure fluctuations on the surface and control the wake flow. Results have shown that the use of porous surfaces leads to an increase of the shear stresses in the inner turbulent boundary layer thickness but significant reduction of the energy content of the larger turbulent structure in the outer layer. It has also been observed that the use of porous material leads to the reduction of the turbulence level within the near wake region and significant elongation of the turbulent structures in both spanwise and streamwise directions.
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