Aerodynamic sound production in low speed flow ducts

Measurements of spoiler aerodynamic noise, generated in a low velocity flow duct and radiated from an open exhaust termination, have been made in the form of sound power spectra. The individual $\text{1}\text{3}$ octave power measurements are satisfactorily collapsed (within ± 3 dB) with the aid of derived theoretical scaling laws. Non-dimensional spectra are presented which permit generalized predictions of flow noise for bluff bodies, including splitter attenuators, mounted in low speed flow ducts.