Two-dimensional new-type high-lift systems with link/straight track mechanism coupling downward deflection of spoiler

In the traditional high-lift system design process, the aerodynamics optimization design and mechanism design are decoupled, which often introduces contradiction and trade-off between them. In this paper, an aerodynamics/ mechanism coupling optimization design is conducted to generate a two-dimensional (2D) new-type high-lift configuration (NHCON) of “droop nose single-slotted Fowler flap link∕straight track mechanism coupling downward deflection of spoiler” for a very large transport aircraft. The NSGA-II algorithm is used to conduct the coupling optimization design. First, the aerodynamics/mechanism coupling optimization is conducted for the landing configuration, and the mechanism parameters are fixed. Second, the pure aerodynamics optimization under the guidance of mechanism is conducted for the takeoff configuration. Compared with the traditional high-lift configuration (THCON) generated using the pure aerodynamics optimization design, the landing and takeoff performances of the NHCON designed using the coupling optimization design are much better due to the application of the downward deflection of spoiler.