Wing twist

Angle of attack

Turbulence

Stall (fluid mechanics)

Engineering

Wind tunnel

Aerospace engineering

Lift coefficient

Aerodynamic force

Wing

Reynolds number

Wing configuration

Aerodynamics

Data mining

Computer science

Physics

Wing loading

Lift (data mining)

Structural engineering

Leading edge

Mechanics

Chinese Journal of Aeronautics

The low-speed wind tunnel experiment is carried out on a simplified aircraft model to explore the influence of wing flexibility on the aircraft aerodynamic performance. The investigation involves the measurements of force, membrane deformation and velocity field at Reynolds number of 5.4 × 104–1.1 × 105. In the lift curves, two peaks are observed. The first peak, corresponding to the stall, is sensitive to the wing flexibility much more than the second peak, which nearly keeps constant. For the optimal case, in comparison with the rigid wing model, the delayed stall of nearly 5° is achieved, and the relative lift increment is about 90%. It is revealed that the lift enhanced region corresponds to the larger deformation and stronger vibration, which leads to stronger flow mixing near the flexible wing surface. Thereby, the leading-edge separation is suppressed, and the aerodynamic performance is improved significantly. Furthermore, the effects of sweep angle and Reynolds number on the aerodynamic characteristics of flexible wing are also presented.

Effects of wing flexibility on aerodynamic performance of an aircraft model