Experiment on dynamic response alleviation of a wing with variable-camber flexible trailing edge

Morphing aircraft can significantly enhance the aerodynamic performance of the aircraft, and variable camber flexible trailing edge is one of the important ways to achieve this. To investigate the dynamic response characteristics and alleviation efficiency of the wing under the dynamic deflection of flexible trailing edge, a variable camber flexible trailing edge wing model was designed and a wind tunnel tests was conducted. The wing model consisted of a bending wing beam and six 3D-printed wing panels. Two variable-camber flexible trailing edge rudder surfaces were installed at the trailing edge of two wing panels. These two rudder surfaces were used for dynamic response excitation and dynamic response alleviation control, respectively. The variable-camber flexible trailing edge rudder surface was composed of a digital actuator, flexible cables, a corrugated plate structure, and a flexible polydimethylsiloxane (PDMS) skin. Ground static and dynamic deflection tests were carried out for the variable-camber flexible trailing edge, so as to investigate the camber deformation law of the trailing edge and the dynamic time-delayed characteristics of the actuator. On this basis, a low-speed wind tunnel test was carried out to investigate the dynamic response law of the wing with variable-camber flexible trailing edge and the dynamic response alleviation efficiency based on variable-camber flexible trailing edge and closed-loop feedback control. The wind tunnel test results show that the wing tip acceleration response and the wing root bending moment increase first and then decrease in the frequency range of 1.5–4 Hz, and it reaches the peak value when approaching the first bending frequency of the wing. After closed-loop feedback control by proportional-integral-derivative (PID) control law and variable-camber flexible trailing edge, the maximum alleviation efficiency of the wing tip acceleration and wing root bending moment is 70.18% and 68.14%, respectively, at a wind speed of 20 m/s and disturbance frequency of 2.2 Hz. A theoretical formula with positive dynamic response alleviation efficiency was proposed, and the influencing mechanism and factors of dynamic response alleviation efficiency were analyzed. © 2024 Beijing University of Aeronautics and Astronautics (BUAA). All rights reserved.