Design and analysis of flexible skin for variable camber wing

Abstract

The variable camber wing can significantly improve the aerodynamic characteristics of the aircraft and is an important form of morphing aircraft. Flexible skin technology is one of the key technologies. According to the skin deformation features of the variable camber wing, a flexible skin form is proposed in this paper. The fishbone-shaped reinforcing structure (FBRS) is applied as the main component of the flexible skin to bear aerodynamic loads. Rubber material with excellent deformation ability wraps the FBRS to obtain a smooth and flat skin surface. Thorn-shaped branches on adjacent FBRSs are arranged in a staggered manner. In order to increase the out-of-plane stiffness of the flexible skin, the flexible skin needs to be used in combination with the corrugated structure. Each wave crest of the corrugated structure is connected with the FBRS of the flexible skin. By setting the wave crest of the corrugated structure into a platform shape, a stable connection between the FBRS and the corrugated structure is maintained. In this paper, the stiffness expressions of FBRS and corrugated structure are derived. The chordwise deformation capacity and out-of-plane bearing capacity of the flexible skin are verified by the method of finite element simulation. The results show that the FBRS can transmit aerodynamic loads well and maintain the smoothness and flatness of the rubber surface. Supported by a corrugated structure, this type of flexible skin has good chordwise deformation ability and high out-of-plane bearing capacity.