Validity of Amiet's Model for Propeller Trailing-Edge Noise

Abstract

This paper presents a fundamental investigation into the validity of the classical model by Amiet for predicting the broadband trailing-edge noise due to rotating blades. This approximate model is compared analytically against a model in which the effects of rotation are treated exactly. Low- and high-frequency limits are identified, within which Amiet's model is in excellent agreement with the exact solution. Estimates of the error of Amiet's model outside of these limits are also provided. The method is illustrated by application to an open propeller, a model cooling fan, and a wind turbine. The use of Amiet's model for treating the effects of rotation can provide substantial reductions in computation time when the unsteady blade response is computed from computationally demanding methods, such as computational fluid dynamics.