基于后缘襟翼偏转的大型客机变弯度技术减阻收益

To satisfy the practical constraints of engineering projects, this study examines the drag reduction caused by morphing trailing-edge wings based on the position of the inner and outer flaps of the wide-body aircraft and the deflection position. Aerodynamic evaluations based on the Reynolds-Averaged Navier-Stokes (RANS) equation are conducted on all the deflection angles of the flaps, obtaining the optimal deflection angle of the trailing edge flaps. Benefits of the variable camber technology are investigated, including the expansion of the design requirements for the buffet and drag-divergence boundary as well as the drag reduction at other non-design points. Furthermore, the far field drag decomposition method is used to explore the drag reduction mechanism of the design results. Results show that at the non-design points of the variable Mach number, the drag reduction can be obtained regardless of the trimming moment. However, the drag is not decreased while considering the trimming moment. With different cruise lift coefficients, the variable camber technology can invariably achieve certain drag reduction when considering the trimming moment. Moreover, the variable camber technology can also slow the trend of shock-induced separation and improve the buffeting characteristics of the wing. The drag reduction evaluation and mechanism analysis of the variable camber technology based on trailing edge flap deflection provide reference for the variable camber design of wide-body airliner wings.