Acoustic absorption by permeable surfaces is numerically investigated for the flow over a trailing edge of a flat plate with a finite thickness. The trailing edge is defined by the homogeneous distribution of pores and the numerical approaches based on a dispersed flow assumption. The Reynolds number based on the chord length varies from 1.35 · 10~5 to 1.35 · 10~6. The numerical findings focus on the noise reduction that is attributed to the coherent flow structures of the wall-bounded turbulence interacting with the trailing edge. The anisotropy-invariant map shows that the two-component axisymmetric turbulence dominates the major part of the porous surface due to the strong generation of vortical structures. The porous surface reduced the overall sound pressure level 3dB to 8dB independent from the direction of the wave propagation.
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