Experimental Studies on Slat Noise Reduction

Abstract

As the noise pollution of aircraft is becoming more and more serious, the airworthiness standard puts more and more strict requirements on the aerodynamic noise level of civil passenger aircraft. The slat noise is the main source of noise during the small angle of attack during the takeoff and landing phases. In this paper, for the aerodynamic noise problem of high-lift airfoil slats, a three-segment wing lifting device model is taken as an experimental model, and the aeroacoustic wind tunnel test is carried out. In order to avoid the influence of flap noise, the slat is fully unfolded and the flap is retracted. The acoustic mechanism of the aerodynamic noise of the slat is studied. Then the aerodynamic noise of the deformed slat is studied. The noise reduction effect and aerodynamic performance of the deformable slat are studied by comparing the reference position with the deformed slat. Finally, the related noise reduction mechanism is discussed.