Three-Dimensional Simulation Analysis of the Influence of Slat Structural Parameters on Slat Aerodynamic Noise

Abstract

Slat aerodynamic noise is one of important components of the frame noise. Adjusting the parameters of the slat structure can suppress the slat noise radiation effectively. Based on the typical multi-element airfoil 30P30N, firstly, by means of adjusting the parameters of slat structure, such as changing relative positions between slat and main airfoil and closing slat gap etc., a new slat profile is obtained; Then, based on the DDES simulation method, the characteristics of vortex distribution is analyzed for the new airfoil structure model, and the directivity and SPL of the far field noise are also investigated; Finally, through comparison analysis of the parameters, the physics of the generation of slat aerodynamic noise is discovered, and effects of slat parameters on the features of slat aerodynamic noise are also obtained. The results of the study show that the vortex strength of the flow around the slat has close relation to the source of slat noise. By means of adjusting slat position parameters and morphing of the slat's trailing edge, the vortex strength of the flow close to the slat cusp is reduced effectively, and further largely reducing the slat noise radiation, which can be achieved with preserving high lift coefficient of the airfoil.