Experimental investigation of rotor/stator interaction noise generation. Model description and aerodynamic measurements

Abstract

An experimental investigation was carried out to study aircraft engine noise generation by rotor/stator interaction. The experiment was designed to enable a first step verification of a theoretical fan noise model and to indicate further developments which may be needed to provide a representative acoustic field modelling for engine duct liner design studies. The experiment was matched to the theoretical model as the rotor was unloaded by using cylindrical rods, and the mean aerodynamic loading on the stator vanes was very low. In this report a detailed description is given of the model, together with the results of rotor wake velocity and stator vane pressure measurements (both steady and unsteady) . Data of some noise measurements in the intake are also presented. The acoustic field downstream of the fan will be extensively measured in forthcoming tests. A comparison between theory and experiment will be reported separately.