This paper will discuss the benchmarking of a prediction method for calculating the sound radiation from rotors operating in inhomogeneous turbulent flows. In this study a series of experiments has been carried out at Virginia Tech on a Sevik rotor with various different inflow conditions and upstream disturbances. Initially attention was focused on the operation of the rotor near a wall so that it ingested the wall boundary layer. However, this lead to some inconsistency at high thrust. In this paper we will consider the rotor operating in the wake of a cylinder for five different cylinder positions, five different yaw angles and 13 different rotor speeds. Six hundred different cases were considered and predictions were carried out for all cases. The results show that the prediction methodology is accurate to within ±2 dB for 50% of the cases, and ±4 dB for 80% of the cases considered when averaged over the frequency range from 0.5 BPF to 4 BPF.
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