Aerospace vehicles, wind tunnel test section walls, and other structures often contain porosity that alters the turbulent boundary layer and radiated noise. A semi-empirical mathematical model is developed to predict and analyze the acoustic radiation from turbulent boundary layers over porous media. The model is an acoustic analogy that depends on local flow-field statistics. These statistics are calculated through a steady Reynolds-averaged Navier-Stokes computational fluid dynamics solver that includes porous material. Acoustic predictions are conducted for four subsonic Mach numbers without a pressure gradient. At each Mach number, four porosities with constant liner depth and porous turbulent length scale are examined along with the non-porous solution. The flow-field is validated through comparison with acoustic measurement. Predictions are conducted to ascertain changes in acoustic radiation with varying porosity. We find that noise is amplified or reduced in a non-intuitive way with the introduction of porosity, variation of frequency, and increase of Mach number.
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