Propeller wake interaction noise with downstream wing: effect of wing sweep, lean, and offset

Abstract

This paper investigates the effect of wing sweep, lean, and offset on the noise generated by the interaction of propeller wakes with a downstream wing. The study makes use of a recently-developed, and non-axisymmetric, theoretical model to predict the interaction noise. For a wing with no sweep, lean or offset, we compare our predictions with those from previously-published work on contra-rotating propellers --- as applied to a propeller with a two-bladed, non-rotating, rear row. A systematic parametric study is then carried out to show the effects of wing sweep, lean, and offset on the radiated noise. The interaction noise is significantly reduced, but only when wing sweep and offset rise above specific values. We also show that loud and quiet regions exist in the far sound field at particular combinations of sweep and offset. In addition, we show the importance of the sense of rotation of the propeller, relative to the direction of sweep and offset. The results presented in this study are intended to help understand the effect of the wing configuration (sweep, lean, and offset) on interaction noise and to provide design guidelines for low-noise propeller-wing architectures.