Component-based Model for Flap Noise Prediction

A component-based model is proposed for flap noise prediction to be used in the context of a comprehensive framework for aircraft noise. The flap noise are decomposed into three distinct acoustic contributions: trailing-edge contribution, low and high frequency side-edge contribution. Except the side-edge noise, the trailing-edge noise is recognized as a comparable contribution in the flap noise. Functions and parameters are derived for the energy conversion efficiency, the normalized spectra and the acoustic directivity. Applications of the model are shown for typical flap noise predictions, which include an isolatedAirbus A320 flap, a half-span Fowler flap and a flap in a high-lift wing. It is demonstrated that themodel proposed is suitable for aircraft noise prediction, with experimental data well predicted.